AML

Lab mouse

Results of preclinical research suggest the Hedgehog signaling pathway works with FLT3-ITD mutations to accelerate the development of acute myeloid leukemia (AML).

This finding prompted investigators to look at Hedgehog signaling as a possible second target for treatment in FLT3-ITD AML.

By combining the FLT3 inhibitor sorafenib with the Hedgehog pathway inhibitor IPI-926 (saridegib), the team found they could limit AML growth in vitro and in vivo.

William Matsui, MD, of the Johns Hopkins University School of Medicine in Baltimore, Maryland, and his colleagues conducted this research and disclosed the results in Science Translational Medicine.

The investigators began this work with the goal of discovering why FLT3 inhibitors have fallen short in treating AML. They analyzed gene expression profiles from AML patients and found abnormally enhanced activity in the Hedgehog signaling pathway.

This pathway, which normally regulates embryonic development, is known to fuel many cancer types, but its role in AML has, thus far, remained unresolved.

In experiments with mice, the investigators found the Hedgehog pathway seemed to work together with FLT3 to accelerate AML development and earlier death.

When the team activated Hedgehog signaling in mice expressing FLT3-ITD, they observed enhanced STAT5 signaling, myeloid progenitor proliferation, and AML development.

“From our data, it appears that Hedgehog signaling is like an accelerator,” Dr Matsui said. “It facilitates the cellular events that lead to cancer, but it itself is not the driver of the whole process.”

The investigators also found that mice with both the FLT3 mutation and Hedgehog activity had a significantly shorter lifespan than mice with FLT3-ITD only—an average of 12 weeks and 40 weeks, respectively.

To build upon these findings, the team tested IPI-926 and sorafenib, both alone and in combination, in mice with AML. They found that mice treated with the combination had significantly fewer leukemic cells in the blood and bone marrow than mice treated with either drug alone.

In addition, 3 of the 5 mice treated with the combination survived past the 16 days of the experiment without any further treatment, but none of the mice treated with sorafenib or IPI-926 alone survived that long.

“When we treat mice that have leukemia with both drugs, they live longer than with either drug alone, and there is a portion of them that don’t die at all,” Dr Matsui noted.

He said it’s likely that Hedgehog signaling is involved in the progression of a number of cancers, and “this study brings home the idea that, in treating these cancers, clinicians may need to inhibit Hedgehog along with specific gene mutations.”

Dr Matsui and his colleagues have begun investigating how Hedgehog inhibitors work when combined with newer drugs that target FLT3 more precisely than sorafenib. If these tests continue to show signs that the two types of inhibitors can fight AML, the investigators think such combination therapy could move on to clinical trials.

Lab mouse

Results of preclinical research suggest the Hedgehog signaling pathway works with FLT3-ITD mutations to accelerate the development of acute myeloid leukemia (AML).

This finding prompted investigators to look at Hedgehog signaling as a possible second target for treatment in FLT3-ITD AML.

By combining the FLT3 inhibitor sorafenib with the Hedgehog pathway inhibitor IPI-926 (saridegib), the team found they could limit AML growth in vitro and in vivo.

William Matsui, MD, of the Johns Hopkins University School of Medicine in Baltimore, Maryland, and his colleagues conducted this research and disclosed the results in Science Translational Medicine.

The investigators began this work with the goal of discovering why FLT3 inhibitors have fallen short in treating AML. They analyzed gene expression profiles from AML patients and found abnormally enhanced activity in the Hedgehog signaling pathway.

This pathway, which normally regulates embryonic development, is known to fuel many cancer types, but its role in AML has, thus far, remained unresolved.

In experiments with mice, the investigators found the Hedgehog pathway seemed to work together with FLT3 to accelerate AML development and earlier death.

When the team activated Hedgehog signaling in mice expressing FLT3-ITD, they observed enhanced STAT5 signaling, myeloid progenitor proliferation, and AML development.

“From our data, it appears that Hedgehog signaling is like an accelerator,” Dr Matsui said. “It facilitates the cellular events that lead to cancer, but it itself is not the driver of the whole process.”

The investigators also found that mice with both the FLT3 mutation and Hedgehog activity had a significantly shorter lifespan than mice with FLT3-ITD only—an average of 12 weeks and 40 weeks, respectively.

To build upon these findings, the team tested IPI-926 and sorafenib, both alone and in combination, in mice with AML. They found that mice treated with the combination had significantly fewer leukemic cells in the blood and bone marrow than mice treated with either drug alone.

In addition, 3 of the 5 mice treated with the combination survived past the 16 days of the experiment without any further treatment, but none of the mice treated with sorafenib or IPI-926 alone survived that long.

“When we treat mice that have leukemia with both drugs, they live longer than with either drug alone, and there is a portion of them that don’t die at all,” Dr Matsui noted.

He said it’s likely that Hedgehog signaling is involved in the progression of a number of cancers, and “this study brings home the idea that, in treating these cancers, clinicians may need to inhibit Hedgehog along with specific gene mutations.”

Dr Matsui and his colleagues have begun investigating how Hedgehog inhibitors work when combined with newer drugs that target FLT3 more precisely than sorafenib. If these tests continue to show signs that the two types of inhibitors can fight AML, the investigators think such combination therapy could move on to clinical trials.

Lab mouse

Results of preclinical research suggest the Hedgehog signaling pathway works with FLT3-ITD mutations to accelerate the development of acute myeloid leukemia (AML).

This finding prompted investigators to look at Hedgehog signaling as a possible second target for treatment in FLT3-ITD AML.

By combining the FLT3 inhibitor sorafenib with the Hedgehog pathway inhibitor IPI-926 (saridegib), the team found they could limit AML growth in vitro and in vivo.

William Matsui, MD, of the Johns Hopkins University School of Medicine in Baltimore, Maryland, and his colleagues conducted this research and disclosed the results in Science Translational Medicine.

The investigators began this work with the goal of discovering why FLT3 inhibitors have fallen short in treating AML. They analyzed gene expression profiles from AML patients and found abnormally enhanced activity in the Hedgehog signaling pathway.

This pathway, which normally regulates embryonic development, is known to fuel many cancer types, but its role in AML has, thus far, remained unresolved.

In experiments with mice, the investigators found the Hedgehog pathway seemed to work together with FLT3 to accelerate AML development and earlier death.

When the team activated Hedgehog signaling in mice expressing FLT3-ITD, they observed enhanced STAT5 signaling, myeloid progenitor proliferation, and AML development.

“From our data, it appears that Hedgehog signaling is like an accelerator,” Dr Matsui said. “It facilitates the cellular events that lead to cancer, but it itself is not the driver of the whole process.”

The investigators also found that mice with both the FLT3 mutation and Hedgehog activity had a significantly shorter lifespan than mice with FLT3-ITD only—an average of 12 weeks and 40 weeks, respectively.

To build upon these findings, the team tested IPI-926 and sorafenib, both alone and in combination, in mice with AML. They found that mice treated with the combination had significantly fewer leukemic cells in the blood and bone marrow than mice treated with either drug alone.

In addition, 3 of the 5 mice treated with the combination survived past the 16 days of the experiment without any further treatment, but none of the mice treated with sorafenib or IPI-926 alone survived that long.

“When we treat mice that have leukemia with both drugs, they live longer than with either drug alone, and there is a portion of them that don’t die at all,” Dr Matsui noted.

He said it’s likely that Hedgehog signaling is involved in the progression of a number of cancers, and “this study brings home the idea that, in treating these cancers, clinicians may need to inhibit Hedgehog along with specific gene mutations.”

Dr Matsui and his colleagues have begun investigating how Hedgehog inhibitors work when combined with newer drugs that target FLT3 more precisely than sorafenib. If these tests continue to show signs that the two types of inhibitors can fight AML, the investigators think such combination therapy could move on to clinical trials.

Attendees at ASCO 2015

© ASCO/Scott Morgan

CHICAGO—A dual inhibitor of FLT3 and Axl may produce more durable responses than other FLT3 inhibitors and improve survival in patients with FLT3-positive, relapsed or refractory acute myeloid leukemia (AML), according to a speaker at the 2015 ASCO Annual Meeting.

The FLT3/Axl inhibitor, ASP2215, has not been compared against other FLT3 inhibitors directly, and the data presented were from a phase 1/2 study.

However, the speaker said ASP2215 provided “potent and sustained” inhibition of FLT3 and produced an overall response rate (ORR) of 52% among FLT3-positive patients.

The median duration of response for these patients was 18 weeks, and their median overall survival was about 27 weeks.

Mark J. Levis, MD, PhD, of the Sidney Kimmel Comprehensive Cancer Center at Johns Hopkins in Baltimore, Maryland, presented these results at ASCO as abstract 7003.*

“We’ve been studying FLT3 inhibitors for a number of years now,” Dr Levis began, “and we think they show significant clinical promise, [but] they also have problems.”

He noted that some of these drugs haven’t been particularly safe or well-tolerated. They can cause gastrointestinal toxicity, hand-foot syndrome, QT prolongation, and myelosuppression.

However, the most intriguing problem with FLT3 inhibitors, according to Dr Levis, is the emergence of resistance-conferring point mutations observed in studies of some of the newer drugs, such as sorafenib and quizartinib.

“So in that context, here we have ASP2215,” Dr Levis said. “This is a type 1 FLT3 tyrosine kinase inhibitor, and, as such, it has activity against not only wild-type and ITD-mutated FLT3 but also against those resistance-conferring point mutations typically found in the activation loop at the so-called gatekeeper residue (F691L).”

With this in mind, he and his colleagues conducted a phase 1/2 trial of ASP2215. The study was sponsored by Astellas Pharma Global Development, Inc., the company developing ASP2215.

The trial was open to patients with relapsed or refractory AML, irrespective of their FLT3 mutation status. The researchers’ goal was to identify a safe, tolerable dose of ASP2215 that fully inhibited FLT3.

The team used a standard 3+3 design, with dose levels ranging from 20 mg to 450 mg once daily. They expanded every cohort until they reached a dose-limiting toxicity.

In all, the trial enrolled 198 patients, 24 in the dose-escalation cohorts and 174 in the dose-expansion cohorts. The patients’ median age was 62 (range, 21-90), and 53.1% were male.

Nearly 66% of patients had FLT3 mutations, 29.4% were FLT3-negative, and 5.2% had unknown FLT3 status. About 35% of patients had received 1 prior line of therapy, 26.3% had 2, 33.5% had 3 or more, and 5.7% had an unknown number of prior therapies.

Safety results

In the 194 patients who were evaluable for safety, treatment-emergent adverse events included diarrhea (13.4%), fatigue (12.4%), AST increase (11.3%), ALT increase (9.3%), thrombocytopenia (7.7%), anemia (7.2%), peripheral edema (7.2%), constipation (6.7%), nausea (6.7%), dizziness (6.2%), vomiting (5.7%), and dysgeusia (5.2%).

Serious adverse events included febrile neutropenia (27.3%), sepsis (11.9%), disease progression (10.3%), pneumonia (8.8%), hypotension (5.7%), and respiratory failure (5.7%).

“The kinds of side effects we saw were typical for a relapsed/refractory AML population,” Dr Levis said. “Nothing really stood out. Any trial of relapsed/refractory AML is going to have febrile neutropenia and sepsis, and those were our dominant, serious adverse events. There was no real safety signal here that was unique to the drug, we felt.”

The researchers said the maximum-tolerated dose of ASP2215 was 300 mg, as 2 patients who received the 450 mg dose experienced dose-limiting toxicities. One was grade 3 diarrhea, and the other was grade 3 AST elevation.

Response and survival

Among the 127 patients who were FLT3-positive, the ORR was 52% (n=66). The complete response (CR) rate was 6.3% (n=8). The composite CR rate, which includes CRs with incomplete hematologic recovery (CRi) and incomplete platelet recovery (CRp), was 40.9% (n=52). And the partial response (PR) rate was 11% (n=14).

“As we scale up the dose, the PRs shift on over to CRis, and the dominant response is, in fact, a complete response with incomplete count recovery,” Dr Levis said. “The categories where we had the largest number of responses were the 120 mg and 200 mg categories. We didn’t really have enough patients in the 300 mg category to comment on it. ”

For the FLT3-positive patients, the median duration of response was 126 days.

“The duration of response really stood out here,” Dr Levis said. “It’s over 4 months. That is something we really didn’t see with the other drugs, and I suspect that is a reflection of the suppression of the outgrowth of these resistance mutations.”

Unfortunately, FLT3-wild-type patients did not fare as well. The ORR among these patients was 8.8%. None of the patients achieved a CR, 3 had a composite CR (5.3%), and 2 had a PR (3.5%).

Among the FLT3-positive patients, the median overall survival was about 27 weeks. It was 128 days in the 20 mg dose cohort (n=13), 105.5 days in the 40 mg cohort (n=8), 201 days in the 80 mg cohort (n=12), 199 days in the 120 mg cohort (n=40), and 161 days in the 200 mg cohort (n=45). Dr Levis did not present survival data for the 300 mg or 450 mg cohorts, which included 7 and 2 patients, respectively.

“[Relapsed/refractory AML] is a population that has a median survival of about 3 months with conventional therapy, at least by historical publications,” Dr Levis noted. “If you look at survival in this trial, patients treated at the FLT3-inhibitory doses [had a] greater than 6-month median survival.”

He added that studies of ASP2215 in combination with other agents are ongoing in patients with newly diagnosed AML. And phase 3 trials of ASP2215 at the 120 mg dose, with the option of scaling up to 200 mg, are planned.

*Information in the abstract differs from that presented at the meeting.

Attendees at ASCO 2015

© ASCO/Scott Morgan

CHICAGO—A dual inhibitor of FLT3 and Axl may produce more durable responses than other FLT3 inhibitors and improve survival in patients with FLT3-positive, relapsed or refractory acute myeloid leukemia (AML), according to a speaker at the 2015 ASCO Annual Meeting.

The FLT3/Axl inhibitor, ASP2215, has not been compared against other FLT3 inhibitors directly, and the data presented were from a phase 1/2 study.

However, the speaker said ASP2215 provided “potent and sustained” inhibition of FLT3 and produced an overall response rate (ORR) of 52% among FLT3-positive patients.

The median duration of response for these patients was 18 weeks, and their median overall survival was about 27 weeks.

Mark J. Levis, MD, PhD, of the Sidney Kimmel Comprehensive Cancer Center at Johns Hopkins in Baltimore, Maryland, presented these results at ASCO as abstract 7003.*

“We’ve been studying FLT3 inhibitors for a number of years now,” Dr Levis began, “and we think they show significant clinical promise, [but] they also have problems.”

He noted that some of these drugs haven’t been particularly safe or well-tolerated. They can cause gastrointestinal toxicity, hand-foot syndrome, QT prolongation, and myelosuppression.

However, the most intriguing problem with FLT3 inhibitors, according to Dr Levis, is the emergence of resistance-conferring point mutations observed in studies of some of the newer drugs, such as sorafenib and quizartinib.

“So in that context, here we have ASP2215,” Dr Levis said. “This is a type 1 FLT3 tyrosine kinase inhibitor, and, as such, it has activity against not only wild-type and ITD-mutated FLT3 but also against those resistance-conferring point mutations typically found in the activation loop at the so-called gatekeeper residue (F691L).”

With this in mind, he and his colleagues conducted a phase 1/2 trial of ASP2215. The study was sponsored by Astellas Pharma Global Development, Inc., the company developing ASP2215.

The trial was open to patients with relapsed or refractory AML, irrespective of their FLT3 mutation status. The researchers’ goal was to identify a safe, tolerable dose of ASP2215 that fully inhibited FLT3.

The team used a standard 3+3 design, with dose levels ranging from 20 mg to 450 mg once daily. They expanded every cohort until they reached a dose-limiting toxicity.

In all, the trial enrolled 198 patients, 24 in the dose-escalation cohorts and 174 in the dose-expansion cohorts. The patients’ median age was 62 (range, 21-90), and 53.1% were male.

Nearly 66% of patients had FLT3 mutations, 29.4% were FLT3-negative, and 5.2% had unknown FLT3 status. About 35% of patients had received 1 prior line of therapy, 26.3% had 2, 33.5% had 3 or more, and 5.7% had an unknown number of prior therapies.

Safety results

In the 194 patients who were evaluable for safety, treatment-emergent adverse events included diarrhea (13.4%), fatigue (12.4%), AST increase (11.3%), ALT increase (9.3%), thrombocytopenia (7.7%), anemia (7.2%), peripheral edema (7.2%), constipation (6.7%), nausea (6.7%), dizziness (6.2%), vomiting (5.7%), and dysgeusia (5.2%).

Serious adverse events included febrile neutropenia (27.3%), sepsis (11.9%), disease progression (10.3%), pneumonia (8.8%), hypotension (5.7%), and respiratory failure (5.7%).

“The kinds of side effects we saw were typical for a relapsed/refractory AML population,” Dr Levis said. “Nothing really stood out. Any trial of relapsed/refractory AML is going to have febrile neutropenia and sepsis, and those were our dominant, serious adverse events. There was no real safety signal here that was unique to the drug, we felt.”

The researchers said the maximum-tolerated dose of ASP2215 was 300 mg, as 2 patients who received the 450 mg dose experienced dose-limiting toxicities. One was grade 3 diarrhea, and the other was grade 3 AST elevation.

Response and survival

Among the 127 patients who were FLT3-positive, the ORR was 52% (n=66). The complete response (CR) rate was 6.3% (n=8). The composite CR rate, which includes CRs with incomplete hematologic recovery (CRi) and incomplete platelet recovery (CRp), was 40.9% (n=52). And the partial response (PR) rate was 11% (n=14).

“As we scale up the dose, the PRs shift on over to CRis, and the dominant response is, in fact, a complete response with incomplete count recovery,” Dr Levis said. “The categories where we had the largest number of responses were the 120 mg and 200 mg categories. We didn’t really have enough patients in the 300 mg category to comment on it. ”

For the FLT3-positive patients, the median duration of response was 126 days.

“The duration of response really stood out here,” Dr Levis said. “It’s over 4 months. That is something we really didn’t see with the other drugs, and I suspect that is a reflection of the suppression of the outgrowth of these resistance mutations.”

Unfortunately, FLT3-wild-type patients did not fare as well. The ORR among these patients was 8.8%. None of the patients achieved a CR, 3 had a composite CR (5.3%), and 2 had a PR (3.5%).

Among the FLT3-positive patients, the median overall survival was about 27 weeks. It was 128 days in the 20 mg dose cohort (n=13), 105.5 days in the 40 mg cohort (n=8), 201 days in the 80 mg cohort (n=12), 199 days in the 120 mg cohort (n=40), and 161 days in the 200 mg cohort (n=45). Dr Levis did not present survival data for the 300 mg or 450 mg cohorts, which included 7 and 2 patients, respectively.

“[Relapsed/refractory AML] is a population that has a median survival of about 3 months with conventional therapy, at least by historical publications,” Dr Levis noted. “If you look at survival in this trial, patients treated at the FLT3-inhibitory doses [had a] greater than 6-month median survival.”

He added that studies of ASP2215 in combination with other agents are ongoing in patients with newly diagnosed AML. And phase 3 trials of ASP2215 at the 120 mg dose, with the option of scaling up to 200 mg, are planned.

*Information in the abstract differs from that presented at the meeting.

Attendees at ASCO 2015

© ASCO/Scott Morgan

CHICAGO—A dual inhibitor of FLT3 and Axl may produce more durable responses than other FLT3 inhibitors and improve survival in patients with FLT3-positive, relapsed or refractory acute myeloid leukemia (AML), according to a speaker at the 2015 ASCO Annual Meeting.

The FLT3/Axl inhibitor, ASP2215, has not been compared against other FLT3 inhibitors directly, and the data presented were from a phase 1/2 study.

However, the speaker said ASP2215 provided “potent and sustained” inhibition of FLT3 and produced an overall response rate (ORR) of 52% among FLT3-positive patients.

The median duration of response for these patients was 18 weeks, and their median overall survival was about 27 weeks.

Mark J. Levis, MD, PhD, of the Sidney Kimmel Comprehensive Cancer Center at Johns Hopkins in Baltimore, Maryland, presented these results at ASCO as abstract 7003.*

“We’ve been studying FLT3 inhibitors for a number of years now,” Dr Levis began, “and we think they show significant clinical promise, [but] they also have problems.”

He noted that some of these drugs haven’t been particularly safe or well-tolerated. They can cause gastrointestinal toxicity, hand-foot syndrome, QT prolongation, and myelosuppression.

However, the most intriguing problem with FLT3 inhibitors, according to Dr Levis, is the emergence of resistance-conferring point mutations observed in studies of some of the newer drugs, such as sorafenib and quizartinib.

“So in that context, here we have ASP2215,” Dr Levis said. “This is a type 1 FLT3 tyrosine kinase inhibitor, and, as such, it has activity against not only wild-type and ITD-mutated FLT3 but also against those resistance-conferring point mutations typically found in the activation loop at the so-called gatekeeper residue (F691L).”

With this in mind, he and his colleagues conducted a phase 1/2 trial of ASP2215. The study was sponsored by Astellas Pharma Global Development, Inc., the company developing ASP2215.

The trial was open to patients with relapsed or refractory AML, irrespective of their FLT3 mutation status. The researchers’ goal was to identify a safe, tolerable dose of ASP2215 that fully inhibited FLT3.

The team used a standard 3+3 design, with dose levels ranging from 20 mg to 450 mg once daily. They expanded every cohort until they reached a dose-limiting toxicity.

In all, the trial enrolled 198 patients, 24 in the dose-escalation cohorts and 174 in the dose-expansion cohorts. The patients’ median age was 62 (range, 21-90), and 53.1% were male.

Nearly 66% of patients had FLT3 mutations, 29.4% were FLT3-negative, and 5.2% had unknown FLT3 status. About 35% of patients had received 1 prior line of therapy, 26.3% had 2, 33.5% had 3 or more, and 5.7% had an unknown number of prior therapies.

Safety results

In the 194 patients who were evaluable for safety, treatment-emergent adverse events included diarrhea (13.4%), fatigue (12.4%), AST increase (11.3%), ALT increase (9.3%), thrombocytopenia (7.7%), anemia (7.2%), peripheral edema (7.2%), constipation (6.7%), nausea (6.7%), dizziness (6.2%), vomiting (5.7%), and dysgeusia (5.2%).

Serious adverse events included febrile neutropenia (27.3%), sepsis (11.9%), disease progression (10.3%), pneumonia (8.8%), hypotension (5.7%), and respiratory failure (5.7%).

“The kinds of side effects we saw were typical for a relapsed/refractory AML population,” Dr Levis said. “Nothing really stood out. Any trial of relapsed/refractory AML is going to have febrile neutropenia and sepsis, and those were our dominant, serious adverse events. There was no real safety signal here that was unique to the drug, we felt.”

The researchers said the maximum-tolerated dose of ASP2215 was 300 mg, as 2 patients who received the 450 mg dose experienced dose-limiting toxicities. One was grade 3 diarrhea, and the other was grade 3 AST elevation.

Response and survival

Among the 127 patients who were FLT3-positive, the ORR was 52% (n=66). The complete response (CR) rate was 6.3% (n=8). The composite CR rate, which includes CRs with incomplete hematologic recovery (CRi) and incomplete platelet recovery (CRp), was 40.9% (n=52). And the partial response (PR) rate was 11% (n=14).

“As we scale up the dose, the PRs shift on over to CRis, and the dominant response is, in fact, a complete response with incomplete count recovery,” Dr Levis said. “The categories where we had the largest number of responses were the 120 mg and 200 mg categories. We didn’t really have enough patients in the 300 mg category to comment on it. ”

For the FLT3-positive patients, the median duration of response was 126 days.

“The duration of response really stood out here,” Dr Levis said. “It’s over 4 months. That is something we really didn’t see with the other drugs, and I suspect that is a reflection of the suppression of the outgrowth of these resistance mutations.”

Unfortunately, FLT3-wild-type patients did not fare as well. The ORR among these patients was 8.8%. None of the patients achieved a CR, 3 had a composite CR (5.3%), and 2 had a PR (3.5%).

Among the FLT3-positive patients, the median overall survival was about 27 weeks. It was 128 days in the 20 mg dose cohort (n=13), 105.5 days in the 40 mg cohort (n=8), 201 days in the 80 mg cohort (n=12), 199 days in the 120 mg cohort (n=40), and 161 days in the 200 mg cohort (n=45). Dr Levis did not present survival data for the 300 mg or 450 mg cohorts, which included 7 and 2 patients, respectively.

“[Relapsed/refractory AML] is a population that has a median survival of about 3 months with conventional therapy, at least by historical publications,” Dr Levis noted. “If you look at survival in this trial, patients treated at the FLT3-inhibitory doses [had a] greater than 6-month median survival.”

He added that studies of ASP2215 in combination with other agents are ongoing in patients with newly diagnosed AML. And phase 3 trials of ASP2215 at the 120 mg dose, with the option of scaling up to 200 mg, are planned.

*Information in the abstract differs from that presented at the meeting.

Peripheral blood stem cell (PBSC) grafts with high doses of CD8 cells were associated with significantly lower relapse risk and improved survival in patients who were treated for hematologic malignancies with reduced-intensity conditioning (RIC) hematopoietic allogeneic stem cell transplantation (allo-HSCT), according to a report online in the Journal of Clinical Oncology.

A multivariate analysis showed that CD8 cell dose was an independent predictor of relapse (adjusted hazard ratio [aHR], 0.43; P = .009), relapse-free survival (aHR, 0.50; P = .006), and overall survival (aHR, 0.57; P = .04). The data showed a linear association between CD8 cell dose and outcomes, and further analysis identified an optimum cutoff of CD8 cell dose (0.72 x 10⁸ CD8 cells per kg) to segregate survival outcomes. Patients who received grafts with CD8 cell doses above the cutoff had significantly improved regression-free and overall survival (P = .005 and P = .007, respectively).

“These findings indicate that improved survival after RIC transplantations could be achieved by optimizing donor selection and PBSC collection to increase the likelihood of mobilizing grafts containing high CD8 cell doses,” wrote Dr. Ran Reshef of the department of medicine at the Hospital of the University of Pennsylvania, Philadelphia, and colleagues (Journ. Clin. Onc. 2015 June 8 [doi:10.1200/JCO.2014.60.1203]).

Younger donors were more likely to have CD8 cell doses above the cutoff (CD8^hi), however, only 53% of donors younger than 30 years had CD8^hi grafts. To find methods to predict graft composition during donor screening, the investigators studied 21 randomly selected allo-HSCT donors. They found no correlations between CD8 graft content and clinical variables such as weight, sex, viral serologies, or apheresis parameters. Donors with a higher proportion of CD8 cells donated grafts with higher CD8 cell dose, but the presence of higher CD4 counts negated this. Screening for the relative proportions of CD8 and CD4 cells identifies donors most likely to mobilize CD8^hi grafts.

“This is also a practical consideration because the assay is rapid, is routinely performed in clinical laboratories, and can easily be done at the time of confirmatory HLA [human leukocyte antigen] typing,” the authors noted. Since the relationship between CD8 dose and survival is linear, the higher the dose the better, even if it is below the cutoff.

Previous studies showed conflicting results regarding the outcome of RIC transplantation with younger unrelated donors versus older sibling donors. Donor age inversely correlates with CD8 cell dose, and the results of this study showed that overall survival was significantly better with younger unrelated donors with a CD8^hi graft, compared with older sibling donors (P = .03). No such benefit was observed with younger unrelated donors with CD8^lo grafts (P = .28), indicating the benefit may rely on CD8 cell dose.

The study evaluated 200 patients with hematologic malignancy who underwent allo-HSCT with fludarabine plus busulfan conditioning from 2007 to 2014 at the Abramson Cancer Center, University of Pennsylvania in Philadelphia. The cumulative relapse incidence was 42% at 1 year and 47% at 5 years. The most common diseases in the cohort were acute myeloid leukemia, myelodysplastic syndrome, and non-Hodgkin lymphoma.

High CD8 dose was associated with an increased, but nonsignificant risk of chronic graft-versus-host disease (GVHD); the risk for nonrelapse mortality was not associated with cell doses.

Peripheral blood stem cell (PBSC) grafts with high doses of CD8 cells were associated with significantly lower relapse risk and improved survival in patients who were treated for hematologic malignancies with reduced-intensity conditioning (RIC) hematopoietic allogeneic stem cell transplantation (allo-HSCT), according to a report online in the Journal of Clinical Oncology.

A multivariate analysis showed that CD8 cell dose was an independent predictor of relapse (adjusted hazard ratio [aHR], 0.43; P = .009), relapse-free survival (aHR, 0.50; P = .006), and overall survival (aHR, 0.57; P = .04). The data showed a linear association between CD8 cell dose and outcomes, and further analysis identified an optimum cutoff of CD8 cell dose (0.72 x 10⁸ CD8 cells per kg) to segregate survival outcomes. Patients who received grafts with CD8 cell doses above the cutoff had significantly improved regression-free and overall survival (P = .005 and P = .007, respectively).

“These findings indicate that improved survival after RIC transplantations could be achieved by optimizing donor selection and PBSC collection to increase the likelihood of mobilizing grafts containing high CD8 cell doses,” wrote Dr. Ran Reshef of the department of medicine at the Hospital of the University of Pennsylvania, Philadelphia, and colleagues (Journ. Clin. Onc. 2015 June 8 [doi:10.1200/JCO.2014.60.1203]).

Younger donors were more likely to have CD8 cell doses above the cutoff (CD8^hi), however, only 53% of donors younger than 30 years had CD8^hi grafts. To find methods to predict graft composition during donor screening, the investigators studied 21 randomly selected allo-HSCT donors. They found no correlations between CD8 graft content and clinical variables such as weight, sex, viral serologies, or apheresis parameters. Donors with a higher proportion of CD8 cells donated grafts with higher CD8 cell dose, but the presence of higher CD4 counts negated this. Screening for the relative proportions of CD8 and CD4 cells identifies donors most likely to mobilize CD8^hi grafts.

“This is also a practical consideration because the assay is rapid, is routinely performed in clinical laboratories, and can easily be done at the time of confirmatory HLA [human leukocyte antigen] typing,” the authors noted. Since the relationship between CD8 dose and survival is linear, the higher the dose the better, even if it is below the cutoff.

Previous studies showed conflicting results regarding the outcome of RIC transplantation with younger unrelated donors versus older sibling donors. Donor age inversely correlates with CD8 cell dose, and the results of this study showed that overall survival was significantly better with younger unrelated donors with a CD8^hi graft, compared with older sibling donors (P = .03). No such benefit was observed with younger unrelated donors with CD8^lo grafts (P = .28), indicating the benefit may rely on CD8 cell dose.

The study evaluated 200 patients with hematologic malignancy who underwent allo-HSCT with fludarabine plus busulfan conditioning from 2007 to 2014 at the Abramson Cancer Center, University of Pennsylvania in Philadelphia. The cumulative relapse incidence was 42% at 1 year and 47% at 5 years. The most common diseases in the cohort were acute myeloid leukemia, myelodysplastic syndrome, and non-Hodgkin lymphoma.

High CD8 dose was associated with an increased, but nonsignificant risk of chronic graft-versus-host disease (GVHD); the risk for nonrelapse mortality was not associated with cell doses.

Peripheral blood stem cell (PBSC) grafts with high doses of CD8 cells were associated with significantly lower relapse risk and improved survival in patients who were treated for hematologic malignancies with reduced-intensity conditioning (RIC) hematopoietic allogeneic stem cell transplantation (allo-HSCT), according to a report online in the Journal of Clinical Oncology.

A multivariate analysis showed that CD8 cell dose was an independent predictor of relapse (adjusted hazard ratio [aHR], 0.43; P = .009), relapse-free survival (aHR, 0.50; P = .006), and overall survival (aHR, 0.57; P = .04). The data showed a linear association between CD8 cell dose and outcomes, and further analysis identified an optimum cutoff of CD8 cell dose (0.72 x 10⁸ CD8 cells per kg) to segregate survival outcomes. Patients who received grafts with CD8 cell doses above the cutoff had significantly improved regression-free and overall survival (P = .005 and P = .007, respectively).

“These findings indicate that improved survival after RIC transplantations could be achieved by optimizing donor selection and PBSC collection to increase the likelihood of mobilizing grafts containing high CD8 cell doses,” wrote Dr. Ran Reshef of the department of medicine at the Hospital of the University of Pennsylvania, Philadelphia, and colleagues (Journ. Clin. Onc. 2015 June 8 [doi:10.1200/JCO.2014.60.1203]).

Younger donors were more likely to have CD8 cell doses above the cutoff (CD8^hi), however, only 53% of donors younger than 30 years had CD8^hi grafts. To find methods to predict graft composition during donor screening, the investigators studied 21 randomly selected allo-HSCT donors. They found no correlations between CD8 graft content and clinical variables such as weight, sex, viral serologies, or apheresis parameters. Donors with a higher proportion of CD8 cells donated grafts with higher CD8 cell dose, but the presence of higher CD4 counts negated this. Screening for the relative proportions of CD8 and CD4 cells identifies donors most likely to mobilize CD8^hi grafts.

“This is also a practical consideration because the assay is rapid, is routinely performed in clinical laboratories, and can easily be done at the time of confirmatory HLA [human leukocyte antigen] typing,” the authors noted. Since the relationship between CD8 dose and survival is linear, the higher the dose the better, even if it is below the cutoff.

Previous studies showed conflicting results regarding the outcome of RIC transplantation with younger unrelated donors versus older sibling donors. Donor age inversely correlates with CD8 cell dose, and the results of this study showed that overall survival was significantly better with younger unrelated donors with a CD8^hi graft, compared with older sibling donors (P = .03). No such benefit was observed with younger unrelated donors with CD8^lo grafts (P = .28), indicating the benefit may rely on CD8 cell dose.

The study evaluated 200 patients with hematologic malignancy who underwent allo-HSCT with fludarabine plus busulfan conditioning from 2007 to 2014 at the Abramson Cancer Center, University of Pennsylvania in Philadelphia. The cumulative relapse incidence was 42% at 1 year and 47% at 5 years. The most common diseases in the cohort were acute myeloid leukemia, myelodysplastic syndrome, and non-Hodgkin lymphoma.

High CD8 dose was associated with an increased, but nonsignificant risk of chronic graft-versus-host disease (GVHD); the risk for nonrelapse mortality was not associated with cell doses.

Crowd at ASCO 2015

© ASCO/Rodney White

CHICAGO—Researchers say they have identified 3 leukemia stem cell (LSC) phenotypes that are correlated with cytogenetic/molecular abnormalities and prognosis in acute myeloid leukemia (AML).

The investigators believe this knowledge could aid risk stratification of AML patients, particularly those without identifiable cytogenetic or molecular risk factors.

The findings may also pave the way for scientists to identify novel therapeutic targets on LSCs and monitor LSCs in response to therapy.

Jonathan Michael Gerber, MD, of Levine Cancer Institute in Charlotte, North Carolina, presented the findings at the 2015 ASCO Annual Meeting (abstract 7000*).

Via previous research, Dr Gerber and his colleagues identified 3 different LSC phenotypes in AML:

• LSCs that are CD34-negative
• LSCs that are CD34-positive, CD38-negative, and have intermediate levels of aldehyde dehydrogenase (ALDH^int)
• LSCs that are CD34-positive, CD38-negative, and have high levels of ALDH (ALDH^high).

With the current study, the researchers wanted to determine if these phenotypes correlate with cytogenetic/molecular features and treatment outcomes.

So they analyzed diagnostic samples from 98 patients with newly diagnosed AML who had normal or unfavorable cytogenetics. The patients were enrolled on a phase 2 trial comparing FLAM and 7+3 (Zeidner et al, haematologica 2015).

Dr Gerber and his colleagues identified 22 patients with CD34^- LSCs, 43 with ALDH^int LSCs, and 33 with ALDH^high LSCs.

Risk factors

“We found that leukemia stem cell phenotype indeed correlated quite strongly with cytogenetic and molecular risk factors,” Dr Gerber said.

NPM1 mutations were more common in patients with CD34^- LSCs (64%) than those with ALDH^int LSCs (14%) or ALDH^high LSCs (6%, P<0.001). NPM1 mutations were the sole abnormality in 50% of patients with CD34^- LSCs.

Poor-risk cytogenetics and/or FLT3-ITD mutations were more common in patients with ALDH^high LSCs (85%) than those with ALDH^int LCSs (35%) or CD34^- LSCs (18%, P<0.001).

Nine percent of patients in the CD34^- LSC group fell into the European Leukemia Network poor-risk category, compared to 73% of patients in the ALDH^high LSC group.

Only 2 patients had 11q23, and both had CD34^- LSCs. Fifty-five percent of patients with ALDH^high LSCs had prior myelodysplastic syndromes or myeloproliferative neoplasms.

Prognosis

“We found that leukemia stem cell phenotype correlated strongly with outcomes as well,” Dr Gerber said. “It turned out that CD34^- patients fared more favorably overall.”

Patients with CD34^- LSCs had the highest complete response rate (86%), followed by those with ALDH^int LSCs (67%) and ALDH^high LSCs (45%, P<0.01).

Patients in the CD34^- group also had a higher rate of event-free survival at 2 years (46%) than patients in the ALDH^int group (26%) or the ALDH^high group (0%). The median event-free survival was 13 months, 11.3 months, and 2.2 months, respectively (P<0.01).

The rate of overall survival at 2 years was best for the CD34^- group (76%), followed by the ALDH^int group (38%) and the ALDH^high group (34%). The median overall survival was not reached, 18.7 months, and 9.4 months, respectively (P=0.02).

Dr Gerber also noted that ALDH^high patients fared much better if they underwent hematopoietic stem cell transplant.

“There is 0% leukemia-free survival at the 2-year mark for the ALDH^high patients who were not transplanted,” he said. “Those that were transplanted fared about the same as everyone else in the series. So it was very striking that there were no chemotherapy survivors in that group.”

In closing, Dr Gerber said this research suggests the 3 LSC phenotypes are mutually exclusive and correlate with cytogenetic and molecular risk factors as well as outcomes in patients with AML.

“This [discovery] may allow for rapid risk stratification in this explosive disease, facilitate enrollment onto induction protocols . . . , and allow us to divert those ALDH^high, very high-risk patients earlier to novel therapies and/or transplant, given that they’re not really helped much by conventional chemotherapy.”

*Information in the abstract differs from that presented at the meeting.

Crowd at ASCO 2015

© ASCO/Rodney White

CHICAGO—Researchers say they have identified 3 leukemia stem cell (LSC) phenotypes that are correlated with cytogenetic/molecular abnormalities and prognosis in acute myeloid leukemia (AML).

The investigators believe this knowledge could aid risk stratification of AML patients, particularly those without identifiable cytogenetic or molecular risk factors.

The findings may also pave the way for scientists to identify novel therapeutic targets on LSCs and monitor LSCs in response to therapy.

Jonathan Michael Gerber, MD, of Levine Cancer Institute in Charlotte, North Carolina, presented the findings at the 2015 ASCO Annual Meeting (abstract 7000*).

Via previous research, Dr Gerber and his colleagues identified 3 different LSC phenotypes in AML:

• LSCs that are CD34-negative
• LSCs that are CD34-positive, CD38-negative, and have intermediate levels of aldehyde dehydrogenase (ALDH^int)
• LSCs that are CD34-positive, CD38-negative, and have high levels of ALDH (ALDH^high).

With the current study, the researchers wanted to determine if these phenotypes correlate with cytogenetic/molecular features and treatment outcomes.

So they analyzed diagnostic samples from 98 patients with newly diagnosed AML who had normal or unfavorable cytogenetics. The patients were enrolled on a phase 2 trial comparing FLAM and 7+3 (Zeidner et al, haematologica 2015).

Dr Gerber and his colleagues identified 22 patients with CD34^- LSCs, 43 with ALDH^int LSCs, and 33 with ALDH^high LSCs.

Risk factors

“We found that leukemia stem cell phenotype indeed correlated quite strongly with cytogenetic and molecular risk factors,” Dr Gerber said.

NPM1 mutations were more common in patients with CD34^- LSCs (64%) than those with ALDH^int LSCs (14%) or ALDH^high LSCs (6%, P<0.001). NPM1 mutations were the sole abnormality in 50% of patients with CD34^- LSCs.

Poor-risk cytogenetics and/or FLT3-ITD mutations were more common in patients with ALDH^high LSCs (85%) than those with ALDH^int LCSs (35%) or CD34^- LSCs (18%, P<0.001).

Nine percent of patients in the CD34^- LSC group fell into the European Leukemia Network poor-risk category, compared to 73% of patients in the ALDH^high LSC group.

Only 2 patients had 11q23, and both had CD34^- LSCs. Fifty-five percent of patients with ALDH^high LSCs had prior myelodysplastic syndromes or myeloproliferative neoplasms.

Prognosis

“We found that leukemia stem cell phenotype correlated strongly with outcomes as well,” Dr Gerber said. “It turned out that CD34^- patients fared more favorably overall.”

Patients with CD34^- LSCs had the highest complete response rate (86%), followed by those with ALDH^int LSCs (67%) and ALDH^high LSCs (45%, P<0.01).

Patients in the CD34^- group also had a higher rate of event-free survival at 2 years (46%) than patients in the ALDH^int group (26%) or the ALDH^high group (0%). The median event-free survival was 13 months, 11.3 months, and 2.2 months, respectively (P<0.01).

The rate of overall survival at 2 years was best for the CD34^- group (76%), followed by the ALDH^int group (38%) and the ALDH^high group (34%). The median overall survival was not reached, 18.7 months, and 9.4 months, respectively (P=0.02).

Dr Gerber also noted that ALDH^high patients fared much better if they underwent hematopoietic stem cell transplant.

“There is 0% leukemia-free survival at the 2-year mark for the ALDH^high patients who were not transplanted,” he said. “Those that were transplanted fared about the same as everyone else in the series. So it was very striking that there were no chemotherapy survivors in that group.”

In closing, Dr Gerber said this research suggests the 3 LSC phenotypes are mutually exclusive and correlate with cytogenetic and molecular risk factors as well as outcomes in patients with AML.

“This [discovery] may allow for rapid risk stratification in this explosive disease, facilitate enrollment onto induction protocols . . . , and allow us to divert those ALDH^high, very high-risk patients earlier to novel therapies and/or transplant, given that they’re not really helped much by conventional chemotherapy.”

*Information in the abstract differs from that presented at the meeting.

Crowd at ASCO 2015

© ASCO/Rodney White

CHICAGO—Researchers say they have identified 3 leukemia stem cell (LSC) phenotypes that are correlated with cytogenetic/molecular abnormalities and prognosis in acute myeloid leukemia (AML).

The investigators believe this knowledge could aid risk stratification of AML patients, particularly those without identifiable cytogenetic or molecular risk factors.

The findings may also pave the way for scientists to identify novel therapeutic targets on LSCs and monitor LSCs in response to therapy.

Jonathan Michael Gerber, MD, of Levine Cancer Institute in Charlotte, North Carolina, presented the findings at the 2015 ASCO Annual Meeting (abstract 7000*).

Via previous research, Dr Gerber and his colleagues identified 3 different LSC phenotypes in AML:

• LSCs that are CD34-negative
• LSCs that are CD34-positive, CD38-negative, and have intermediate levels of aldehyde dehydrogenase (ALDH^int)
• LSCs that are CD34-positive, CD38-negative, and have high levels of ALDH (ALDH^high).

With the current study, the researchers wanted to determine if these phenotypes correlate with cytogenetic/molecular features and treatment outcomes.

So they analyzed diagnostic samples from 98 patients with newly diagnosed AML who had normal or unfavorable cytogenetics. The patients were enrolled on a phase 2 trial comparing FLAM and 7+3 (Zeidner et al, haematologica 2015).

Dr Gerber and his colleagues identified 22 patients with CD34^- LSCs, 43 with ALDH^int LSCs, and 33 with ALDH^high LSCs.

Risk factors

“We found that leukemia stem cell phenotype indeed correlated quite strongly with cytogenetic and molecular risk factors,” Dr Gerber said.

NPM1 mutations were more common in patients with CD34^- LSCs (64%) than those with ALDH^int LSCs (14%) or ALDH^high LSCs (6%, P<0.001). NPM1 mutations were the sole abnormality in 50% of patients with CD34^- LSCs.

Poor-risk cytogenetics and/or FLT3-ITD mutations were more common in patients with ALDH^high LSCs (85%) than those with ALDH^int LCSs (35%) or CD34^- LSCs (18%, P<0.001).

Nine percent of patients in the CD34^- LSC group fell into the European Leukemia Network poor-risk category, compared to 73% of patients in the ALDH^high LSC group.

Only 2 patients had 11q23, and both had CD34^- LSCs. Fifty-five percent of patients with ALDH^high LSCs had prior myelodysplastic syndromes or myeloproliferative neoplasms.

Prognosis

“We found that leukemia stem cell phenotype correlated strongly with outcomes as well,” Dr Gerber said. “It turned out that CD34^- patients fared more favorably overall.”

Patients with CD34^- LSCs had the highest complete response rate (86%), followed by those with ALDH^int LSCs (67%) and ALDH^high LSCs (45%, P<0.01).

Patients in the CD34^- group also had a higher rate of event-free survival at 2 years (46%) than patients in the ALDH^int group (26%) or the ALDH^high group (0%). The median event-free survival was 13 months, 11.3 months, and 2.2 months, respectively (P<0.01).

The rate of overall survival at 2 years was best for the CD34^- group (76%), followed by the ALDH^int group (38%) and the ALDH^high group (34%). The median overall survival was not reached, 18.7 months, and 9.4 months, respectively (P=0.02).

Dr Gerber also noted that ALDH^high patients fared much better if they underwent hematopoietic stem cell transplant.

“There is 0% leukemia-free survival at the 2-year mark for the ALDH^high patients who were not transplanted,” he said. “Those that were transplanted fared about the same as everyone else in the series. So it was very striking that there were no chemotherapy survivors in that group.”

In closing, Dr Gerber said this research suggests the 3 LSC phenotypes are mutually exclusive and correlate with cytogenetic and molecular risk factors as well as outcomes in patients with AML.

“This [discovery] may allow for rapid risk stratification in this explosive disease, facilitate enrollment onto induction protocols . . . , and allow us to divert those ALDH^high, very high-risk patients earlier to novel therapies and/or transplant, given that they’re not really helped much by conventional chemotherapy.”

*Information in the abstract differs from that presented at the meeting.

Cynomolgus monkey

Photo by Sakurai Midori

An artificial antibody that redirects T cells to target cancer cells shows promise for treating acute myeloid leukemia (AML), according to preclinical research.

The antibody, MGD006, induced tumor regression in mouse models of AML and was largely well-tolerated in cynomolgus monkeys.

Investigators say these results support clinical testing of MGD006 in AML, which is currently underway.

MGD006 is a humanized, dual-affinity re-targeting (DART) molecule that combines a portion of an antibody recognizing CD3, an activating molecule expressed by T cells, with an arm that recognizes CD123.

MGD006 redirects T cells to kill cells expressing CD123, which is upregulated in AML and other hematologic diseases.

Gurunadh Chichili, PhD, of MacroGenics, Inc., in Rockville, Maryland, and his colleagues described their work with MGD006 in Science Translational Medicine. MacroGenics, the company developing MGD006, funded this research.

Because MGD006 is designed to be cleared rapidly, it requires continuous delivery. So in mice, the investigators administered the molecule continuously for up to a week via peritoneally implanted osmotic pumps.

The NSG/b2m^−/− mice had been reconstituted with human peripheral blood mononuclear cells and grafted with KG-1a cells, an AML-M0 line. The mice received MGD006 after tumors were allowed to grow to an average size of about 100 mm³.

Treated mice experienced significant tumor regression at all doses of MGD006 (P<0.005), but there was no activity in mice treated with a control DART molecule. The investigators found that 500 ng/kg of MGD006 per day was sufficient to completely eliminate leukemic cells.

The team also tested MGD006 in macaques and found the molecule binds to human and cynomolgus monkey antigens with similar affinities and redirects T cells from either species to kill CD123-expressing target cells.

The monkeys received continuous infusions of MGD006, starting at 0.1 mg/kg per day and escalating weekly to up to 1 mg/kg per day for a 4-week period. The treatment depleted circulating CD123-positive cells beginning at 72 hours and continuing throughout the infusion period.

The monkeys experienced cytokine release, but it was transient and most significant after the first dose of MDG006. After the first dose, IL-6 concentration returned to baseline by 72 hours, and the magnitude of IL-6 response decreased with each successive MGD006 infusion, even when the dose was increased.

The animals experienced reversible reductions in hematocrit and red cell mass at the highest doses of MDG006 but no neutropenia or thrombocytopenia.

“This research paved the way for our initiation of a phase 1 clinical study of MGD006 in 2014,” said Scott Koenig, MD, PhD, President and CEO of MacroGenics.

“MGD006 has demonstrated great promise as a T-cell-redirected cancer immunotherapy in preclinical studies. We are hopeful that these studies will translate into clinical trial results indicative of clinical improvement for patients with AML, myelodysplastic syndrome, and several other forms of leukemia and lymphoma.”

Cynomolgus monkey

Photo by Sakurai Midori

An artificial antibody that redirects T cells to target cancer cells shows promise for treating acute myeloid leukemia (AML), according to preclinical research.

The antibody, MGD006, induced tumor regression in mouse models of AML and was largely well-tolerated in cynomolgus monkeys.

Investigators say these results support clinical testing of MGD006 in AML, which is currently underway.

MGD006 is a humanized, dual-affinity re-targeting (DART) molecule that combines a portion of an antibody recognizing CD3, an activating molecule expressed by T cells, with an arm that recognizes CD123.

MGD006 redirects T cells to kill cells expressing CD123, which is upregulated in AML and other hematologic diseases.

Gurunadh Chichili, PhD, of MacroGenics, Inc., in Rockville, Maryland, and his colleagues described their work with MGD006 in Science Translational Medicine. MacroGenics, the company developing MGD006, funded this research.

Because MGD006 is designed to be cleared rapidly, it requires continuous delivery. So in mice, the investigators administered the molecule continuously for up to a week via peritoneally implanted osmotic pumps.

The NSG/b2m^−/− mice had been reconstituted with human peripheral blood mononuclear cells and grafted with KG-1a cells, an AML-M0 line. The mice received MGD006 after tumors were allowed to grow to an average size of about 100 mm³.

Treated mice experienced significant tumor regression at all doses of MGD006 (P<0.005), but there was no activity in mice treated with a control DART molecule. The investigators found that 500 ng/kg of MGD006 per day was sufficient to completely eliminate leukemic cells.

The team also tested MGD006 in macaques and found the molecule binds to human and cynomolgus monkey antigens with similar affinities and redirects T cells from either species to kill CD123-expressing target cells.

The monkeys received continuous infusions of MGD006, starting at 0.1 mg/kg per day and escalating weekly to up to 1 mg/kg per day for a 4-week period. The treatment depleted circulating CD123-positive cells beginning at 72 hours and continuing throughout the infusion period.

The monkeys experienced cytokine release, but it was transient and most significant after the first dose of MDG006. After the first dose, IL-6 concentration returned to baseline by 72 hours, and the magnitude of IL-6 response decreased with each successive MGD006 infusion, even when the dose was increased.

The animals experienced reversible reductions in hematocrit and red cell mass at the highest doses of MDG006 but no neutropenia or thrombocytopenia.

“This research paved the way for our initiation of a phase 1 clinical study of MGD006 in 2014,” said Scott Koenig, MD, PhD, President and CEO of MacroGenics.

“MGD006 has demonstrated great promise as a T-cell-redirected cancer immunotherapy in preclinical studies. We are hopeful that these studies will translate into clinical trial results indicative of clinical improvement for patients with AML, myelodysplastic syndrome, and several other forms of leukemia and lymphoma.”

Cynomolgus monkey

Photo by Sakurai Midori

An artificial antibody that redirects T cells to target cancer cells shows promise for treating acute myeloid leukemia (AML), according to preclinical research.

The antibody, MGD006, induced tumor regression in mouse models of AML and was largely well-tolerated in cynomolgus monkeys.

Investigators say these results support clinical testing of MGD006 in AML, which is currently underway.

MGD006 is a humanized, dual-affinity re-targeting (DART) molecule that combines a portion of an antibody recognizing CD3, an activating molecule expressed by T cells, with an arm that recognizes CD123.

MGD006 redirects T cells to kill cells expressing CD123, which is upregulated in AML and other hematologic diseases.

Gurunadh Chichili, PhD, of MacroGenics, Inc., in Rockville, Maryland, and his colleagues described their work with MGD006 in Science Translational Medicine. MacroGenics, the company developing MGD006, funded this research.

Because MGD006 is designed to be cleared rapidly, it requires continuous delivery. So in mice, the investigators administered the molecule continuously for up to a week via peritoneally implanted osmotic pumps.

The NSG/b2m^−/− mice had been reconstituted with human peripheral blood mononuclear cells and grafted with KG-1a cells, an AML-M0 line. The mice received MGD006 after tumors were allowed to grow to an average size of about 100 mm³.

Treated mice experienced significant tumor regression at all doses of MGD006 (P<0.005), but there was no activity in mice treated with a control DART molecule. The investigators found that 500 ng/kg of MGD006 per day was sufficient to completely eliminate leukemic cells.

The team also tested MGD006 in macaques and found the molecule binds to human and cynomolgus monkey antigens with similar affinities and redirects T cells from either species to kill CD123-expressing target cells.

The monkeys received continuous infusions of MGD006, starting at 0.1 mg/kg per day and escalating weekly to up to 1 mg/kg per day for a 4-week period. The treatment depleted circulating CD123-positive cells beginning at 72 hours and continuing throughout the infusion period.

The monkeys experienced cytokine release, but it was transient and most significant after the first dose of MDG006. After the first dose, IL-6 concentration returned to baseline by 72 hours, and the magnitude of IL-6 response decreased with each successive MGD006 infusion, even when the dose was increased.

The animals experienced reversible reductions in hematocrit and red cell mass at the highest doses of MDG006 but no neutropenia or thrombocytopenia.

“This research paved the way for our initiation of a phase 1 clinical study of MGD006 in 2014,” said Scott Koenig, MD, PhD, President and CEO of MacroGenics.

“MGD006 has demonstrated great promise as a T-cell-redirected cancer immunotherapy in preclinical studies. We are hopeful that these studies will translate into clinical trial results indicative of clinical improvement for patients with AML, myelodysplastic syndrome, and several other forms of leukemia and lymphoma.”

Exposure to dexrazoxane among pediatric patients with leukemia or lymphoma did not affect overall mortality during a median follow-up period of 12.6 years, according to a report published online in the Journal of Clinical Oncology.

Aggregated data from three Children’s Oncology Group trials showed that among 1,008 pediatric patients who received treatment with doxorubicin with or without dexrazoxane (DRZ) from 1996 to 2001, exposure to DRZ was not associated with an increased risk of relapse (HR, 0.81; 95% CI, 0.60-1.08) or death (HR, 1.03; 0.73-1.45). Comparing DRZ with non-DRZ treatment groups at 10 years, the cumulative incidence of relapse was 16.1% vs. 19.1% (difference, – 3.0%; 95% CI, – 7.9% to 0.2%) and overall mortality was 12.8% vs. 12.2% (difference, – 0.6%; 95% CI, – 3.5% to 4.7%). The three trials (P9404, P9425, and P9426) evaluated individually likewise did not show significant differences in relapse or mortality rates.

Although studies in adults show a positive effect of DRZ on heart failure rates after anthracycline therapy, concern over DRZ interference with cancer therapies and a possible link to second cancers have limited its use in children and prompted Dr. Eric Chow of the Fred Hutchinson Cancer Research Center, Seattle, and his colleagues to assess the effect of DRZ on mortality.

The investigators wrote that DRZ “does not appear to interfere with cancer treatment efficacy, in terms of original cancer mortality or overall risk of relapse. Although the risk for secondary cancer mortality (mainly as a result of AML/MDS [acute myeloid leukemia/myelodysplastic syndrome]) was greater among those exposed to DRZ, the overall number of events was small, and the differences were not statistically significant,” the investigators said. (J. Clin. Oncol. 2015 May 26 [doi:10.1200/JCO.2014.59.4473])

Aggregated data from the three trials shows that the 10-year mortality rate of AML/MDS was 1.4% for those treated with DRZ (seven patients), compared with 0.8% for those treated without DRZ (five patients).

The beneficial effects of DRZ in decreasing the risk of heart failure have been observed in trials of adult patients, but the results for survivors of childhood cancers have been inconclusive because heart failure may develop over a longer time period in children. With the median age of survivors in this study of 24 years, significant differences in cardiac mortality due to DRZ use are not detectable. To evaluate DRZ as a cardioprotectant, a new Children’s Oncology Group study (Effects of Dexrazoxane Hydrochloride on Biomarkers Associated With Cardiomyopathy and Heart Failure After Cancer Treatment [HEART]) will determine the cardiovascular health of individuals in the three trials P9404, P9425, and P9426.

“Given that second cancers and symptomatic cardiac disease appear to be by far the two most common categories of serious late effects (in terms of both absolute and relative risks) among long-term childhood cancer survivors as a group … with cumulative incidences of each approaching 20% by age 50 years, any strategy that offers the promise of reduced cardiotoxicity without being offset by second cancers is highly attractive,” Dr. Chow and his associates wrote.

The study was supported by the National Institutes of Health, St. Baldrick’s Foundation, and the Leukemia and Lymphoma Society. Dr. Chow reported having no relevant financial conflicts. Three of his coauthors reported having financial relationships with industry.

Exposure to dexrazoxane among pediatric patients with leukemia or lymphoma did not affect overall mortality during a median follow-up period of 12.6 years, according to a report published online in the Journal of Clinical Oncology.

Aggregated data from three Children’s Oncology Group trials showed that among 1,008 pediatric patients who received treatment with doxorubicin with or without dexrazoxane (DRZ) from 1996 to 2001, exposure to DRZ was not associated with an increased risk of relapse (HR, 0.81; 95% CI, 0.60-1.08) or death (HR, 1.03; 0.73-1.45). Comparing DRZ with non-DRZ treatment groups at 10 years, the cumulative incidence of relapse was 16.1% vs. 19.1% (difference, – 3.0%; 95% CI, – 7.9% to 0.2%) and overall mortality was 12.8% vs. 12.2% (difference, – 0.6%; 95% CI, – 3.5% to 4.7%). The three trials (P9404, P9425, and P9426) evaluated individually likewise did not show significant differences in relapse or mortality rates.

Although studies in adults show a positive effect of DRZ on heart failure rates after anthracycline therapy, concern over DRZ interference with cancer therapies and a possible link to second cancers have limited its use in children and prompted Dr. Eric Chow of the Fred Hutchinson Cancer Research Center, Seattle, and his colleagues to assess the effect of DRZ on mortality.

The investigators wrote that DRZ “does not appear to interfere with cancer treatment efficacy, in terms of original cancer mortality or overall risk of relapse. Although the risk for secondary cancer mortality (mainly as a result of AML/MDS [acute myeloid leukemia/myelodysplastic syndrome]) was greater among those exposed to DRZ, the overall number of events was small, and the differences were not statistically significant,” the investigators said. (J. Clin. Oncol. 2015 May 26 [doi:10.1200/JCO.2014.59.4473])

Aggregated data from the three trials shows that the 10-year mortality rate of AML/MDS was 1.4% for those treated with DRZ (seven patients), compared with 0.8% for those treated without DRZ (five patients).

The beneficial effects of DRZ in decreasing the risk of heart failure have been observed in trials of adult patients, but the results for survivors of childhood cancers have been inconclusive because heart failure may develop over a longer time period in children. With the median age of survivors in this study of 24 years, significant differences in cardiac mortality due to DRZ use are not detectable. To evaluate DRZ as a cardioprotectant, a new Children’s Oncology Group study (Effects of Dexrazoxane Hydrochloride on Biomarkers Associated With Cardiomyopathy and Heart Failure After Cancer Treatment [HEART]) will determine the cardiovascular health of individuals in the three trials P9404, P9425, and P9426.

“Given that second cancers and symptomatic cardiac disease appear to be by far the two most common categories of serious late effects (in terms of both absolute and relative risks) among long-term childhood cancer survivors as a group … with cumulative incidences of each approaching 20% by age 50 years, any strategy that offers the promise of reduced cardiotoxicity without being offset by second cancers is highly attractive,” Dr. Chow and his associates wrote.

The study was supported by the National Institutes of Health, St. Baldrick’s Foundation, and the Leukemia and Lymphoma Society. Dr. Chow reported having no relevant financial conflicts. Three of his coauthors reported having financial relationships with industry.

Exposure to dexrazoxane among pediatric patients with leukemia or lymphoma did not affect overall mortality during a median follow-up period of 12.6 years, according to a report published online in the Journal of Clinical Oncology.

Aggregated data from three Children’s Oncology Group trials showed that among 1,008 pediatric patients who received treatment with doxorubicin with or without dexrazoxane (DRZ) from 1996 to 2001, exposure to DRZ was not associated with an increased risk of relapse (HR, 0.81; 95% CI, 0.60-1.08) or death (HR, 1.03; 0.73-1.45). Comparing DRZ with non-DRZ treatment groups at 10 years, the cumulative incidence of relapse was 16.1% vs. 19.1% (difference, – 3.0%; 95% CI, – 7.9% to 0.2%) and overall mortality was 12.8% vs. 12.2% (difference, – 0.6%; 95% CI, – 3.5% to 4.7%). The three trials (P9404, P9425, and P9426) evaluated individually likewise did not show significant differences in relapse or mortality rates.

Although studies in adults show a positive effect of DRZ on heart failure rates after anthracycline therapy, concern over DRZ interference with cancer therapies and a possible link to second cancers have limited its use in children and prompted Dr. Eric Chow of the Fred Hutchinson Cancer Research Center, Seattle, and his colleagues to assess the effect of DRZ on mortality.

The investigators wrote that DRZ “does not appear to interfere with cancer treatment efficacy, in terms of original cancer mortality or overall risk of relapse. Although the risk for secondary cancer mortality (mainly as a result of AML/MDS [acute myeloid leukemia/myelodysplastic syndrome]) was greater among those exposed to DRZ, the overall number of events was small, and the differences were not statistically significant,” the investigators said. (J. Clin. Oncol. 2015 May 26 [doi:10.1200/JCO.2014.59.4473])

Aggregated data from the three trials shows that the 10-year mortality rate of AML/MDS was 1.4% for those treated with DRZ (seven patients), compared with 0.8% for those treated without DRZ (five patients).

The beneficial effects of DRZ in decreasing the risk of heart failure have been observed in trials of adult patients, but the results for survivors of childhood cancers have been inconclusive because heart failure may develop over a longer time period in children. With the median age of survivors in this study of 24 years, significant differences in cardiac mortality due to DRZ use are not detectable. To evaluate DRZ as a cardioprotectant, a new Children’s Oncology Group study (Effects of Dexrazoxane Hydrochloride on Biomarkers Associated With Cardiomyopathy and Heart Failure After Cancer Treatment [HEART]) will determine the cardiovascular health of individuals in the three trials P9404, P9425, and P9426.

“Given that second cancers and symptomatic cardiac disease appear to be by far the two most common categories of serious late effects (in terms of both absolute and relative risks) among long-term childhood cancer survivors as a group … with cumulative incidences of each approaching 20% by age 50 years, any strategy that offers the promise of reduced cardiotoxicity without being offset by second cancers is highly attractive,” Dr. Chow and his associates wrote.

The study was supported by the National Institutes of Health, St. Baldrick’s Foundation, and the Leukemia and Lymphoma Society. Dr. Chow reported having no relevant financial conflicts. Three of his coauthors reported having financial relationships with industry.

Micrograph showing AML

The US Food and Drug Administration (FDA) has granted fast track designation to AG-120 for the treatment of patients with acute myelogenous leukemia (AML) who harbor an isocitrate dehydrogenase-1 (IDH1) mutation.

AG-120 is an oral, selective inhibitor of the mutated IDH1 protein that is under investigation in two phase 1 clinical trials, one in hematologic malignancies and one in advanced solid tumors.

Data from the phase 1 trial in hematologic malignancies were previously presented at the 26th EORTC-NCI-AACR Symposium on Molecular Targets and Cancer Therapeutics in November 2014.

Updated data from this trial are scheduled to be presented at the 20th Annual Congress of the European Hematology Association (EHA) next month.

About fast track designation

The FDA’s fast track drug development program is designed to expedite clinical development and submission of new drug applications for medicines with the potential to treat serious or life-threatening conditions and address unmet medical needs.

Fast track designation facilitates frequent interactions with the FDA review team, including meetings to discuss all aspects of development to support a drug’s approval, and also provides the opportunity to submit sections of a new drug application on a rolling basis as data become available.

“We are pleased that now both AG-120 and AG-221 have been granted fast track designation, demonstrating the FDA’s commitment to facilitate the development and expedite the review of our lead IDH programs as important new therapies for people with AML who carry these mutations,” said Chris Bowden, MD, chief medical officer of Agios Pharmaceuticals, Inc., the company developing AG-120 in cooperation with Celgene Corporation.

Phase 1 results

At the EORTC-NCI-AACR symposium, researchers presented results from the ongoing phase 1 trial of AG-120 in hematologic malignancies. The data included 17 patients with relapsed and/or refractory AML who had received a median of 2 prior treatments.

The patients were scheduled to receive AG-120 in 1 of 4 dose groups: 100 mg twice a day, 300 mg once a day, 500 mg once a day, and 800 mg once a day over continuous, 28-day cycles.

Of the 14 patients evaluable for response, 7 responded. Four patients achieved a complete response, 2 had a complete response in the marrow, and 1 had a partial response.

Responses occurred at all the dose levels tested. The maximum-tolerated dose was not reached. All responding patients were still on AG-120 at the time of presentation, and 1 patient with stable disease remained on the drug.

Researchers said AG-120 was generally well-tolerated. The majority of adverse events were grade 1 and 2. The most common of these were nausea, fatigue, and dyspnea.

Eight patients experienced serious adverse events, but these were primarily related to disease progression.

One patient experienced a dose-limiting toxicity of asymptomatic grade 3 QT prolongation at the highest dose tested, which improved to grade 1 with dose reduction. The patient was in complete remission and remained on AG-120 at the time of presentation.

There were 6 patient deaths, all unrelated to AG-120. Five deaths occurred after patients discontinued treatment due to progressive disease, and 1 patient died due to disease-related intracranial hemorrhage while on treatment.

“We look forward to presenting new data from the ongoing phase 1 study at the EHA Annual Congress next month,” Dr Bowden said, “and remain on track to initiate a global, registration-enabling, phase 3 study in collaboration with Celgene in AML patients who harbor an IDH1 mutation in the first half of 2016.”

Micrograph showing AML

The US Food and Drug Administration (FDA) has granted fast track designation to AG-120 for the treatment of patients with acute myelogenous leukemia (AML) who harbor an isocitrate dehydrogenase-1 (IDH1) mutation.

AG-120 is an oral, selective inhibitor of the mutated IDH1 protein that is under investigation in two phase 1 clinical trials, one in hematologic malignancies and one in advanced solid tumors.

Data from the phase 1 trial in hematologic malignancies were previously presented at the 26th EORTC-NCI-AACR Symposium on Molecular Targets and Cancer Therapeutics in November 2014.

Updated data from this trial are scheduled to be presented at the 20th Annual Congress of the European Hematology Association (EHA) next month.

About fast track designation

The FDA’s fast track drug development program is designed to expedite clinical development and submission of new drug applications for medicines with the potential to treat serious or life-threatening conditions and address unmet medical needs.

Fast track designation facilitates frequent interactions with the FDA review team, including meetings to discuss all aspects of development to support a drug’s approval, and also provides the opportunity to submit sections of a new drug application on a rolling basis as data become available.

“We are pleased that now both AG-120 and AG-221 have been granted fast track designation, demonstrating the FDA’s commitment to facilitate the development and expedite the review of our lead IDH programs as important new therapies for people with AML who carry these mutations,” said Chris Bowden, MD, chief medical officer of Agios Pharmaceuticals, Inc., the company developing AG-120 in cooperation with Celgene Corporation.

Phase 1 results

At the EORTC-NCI-AACR symposium, researchers presented results from the ongoing phase 1 trial of AG-120 in hematologic malignancies. The data included 17 patients with relapsed and/or refractory AML who had received a median of 2 prior treatments.

The patients were scheduled to receive AG-120 in 1 of 4 dose groups: 100 mg twice a day, 300 mg once a day, 500 mg once a day, and 800 mg once a day over continuous, 28-day cycles.

Of the 14 patients evaluable for response, 7 responded. Four patients achieved a complete response, 2 had a complete response in the marrow, and 1 had a partial response.

Responses occurred at all the dose levels tested. The maximum-tolerated dose was not reached. All responding patients were still on AG-120 at the time of presentation, and 1 patient with stable disease remained on the drug.

Researchers said AG-120 was generally well-tolerated. The majority of adverse events were grade 1 and 2. The most common of these were nausea, fatigue, and dyspnea.

Eight patients experienced serious adverse events, but these were primarily related to disease progression.

One patient experienced a dose-limiting toxicity of asymptomatic grade 3 QT prolongation at the highest dose tested, which improved to grade 1 with dose reduction. The patient was in complete remission and remained on AG-120 at the time of presentation.

There were 6 patient deaths, all unrelated to AG-120. Five deaths occurred after patients discontinued treatment due to progressive disease, and 1 patient died due to disease-related intracranial hemorrhage while on treatment.

“We look forward to presenting new data from the ongoing phase 1 study at the EHA Annual Congress next month,” Dr Bowden said, “and remain on track to initiate a global, registration-enabling, phase 3 study in collaboration with Celgene in AML patients who harbor an IDH1 mutation in the first half of 2016.”

Micrograph showing AML

The US Food and Drug Administration (FDA) has granted fast track designation to AG-120 for the treatment of patients with acute myelogenous leukemia (AML) who harbor an isocitrate dehydrogenase-1 (IDH1) mutation.

AG-120 is an oral, selective inhibitor of the mutated IDH1 protein that is under investigation in two phase 1 clinical trials, one in hematologic malignancies and one in advanced solid tumors.

Data from the phase 1 trial in hematologic malignancies were previously presented at the 26th EORTC-NCI-AACR Symposium on Molecular Targets and Cancer Therapeutics in November 2014.

Updated data from this trial are scheduled to be presented at the 20th Annual Congress of the European Hematology Association (EHA) next month.

About fast track designation

The FDA’s fast track drug development program is designed to expedite clinical development and submission of new drug applications for medicines with the potential to treat serious or life-threatening conditions and address unmet medical needs.

Fast track designation facilitates frequent interactions with the FDA review team, including meetings to discuss all aspects of development to support a drug’s approval, and also provides the opportunity to submit sections of a new drug application on a rolling basis as data become available.

“We are pleased that now both AG-120 and AG-221 have been granted fast track designation, demonstrating the FDA’s commitment to facilitate the development and expedite the review of our lead IDH programs as important new therapies for people with AML who carry these mutations,” said Chris Bowden, MD, chief medical officer of Agios Pharmaceuticals, Inc., the company developing AG-120 in cooperation with Celgene Corporation.

Phase 1 results

At the EORTC-NCI-AACR symposium, researchers presented results from the ongoing phase 1 trial of AG-120 in hematologic malignancies. The data included 17 patients with relapsed and/or refractory AML who had received a median of 2 prior treatments.

The patients were scheduled to receive AG-120 in 1 of 4 dose groups: 100 mg twice a day, 300 mg once a day, 500 mg once a day, and 800 mg once a day over continuous, 28-day cycles.

Of the 14 patients evaluable for response, 7 responded. Four patients achieved a complete response, 2 had a complete response in the marrow, and 1 had a partial response.

Responses occurred at all the dose levels tested. The maximum-tolerated dose was not reached. All responding patients were still on AG-120 at the time of presentation, and 1 patient with stable disease remained on the drug.

Researchers said AG-120 was generally well-tolerated. The majority of adverse events were grade 1 and 2. The most common of these were nausea, fatigue, and dyspnea.

Eight patients experienced serious adverse events, but these were primarily related to disease progression.

One patient experienced a dose-limiting toxicity of asymptomatic grade 3 QT prolongation at the highest dose tested, which improved to grade 1 with dose reduction. The patient was in complete remission and remained on AG-120 at the time of presentation.

There were 6 patient deaths, all unrelated to AG-120. Five deaths occurred after patients discontinued treatment due to progressive disease, and 1 patient died due to disease-related intracranial hemorrhage while on treatment.

“We look forward to presenting new data from the ongoing phase 1 study at the EHA Annual Congress next month,” Dr Bowden said, “and remain on track to initiate a global, registration-enabling, phase 3 study in collaboration with Celgene in AML patients who harbor an IDH1 mutation in the first half of 2016.”

Micrograph showing BL

Image by Ed Uthman

Combining a cholesterol-lowering drug and a contraceptive steroid could be a safe, effective treatment for leukemias, lymphomas, and other malignancies, according to researchers.

Their work helps explain how this combination treatment, bezafibrate and medroxyprogesterone acetate (BaP), kills cancer cells.

The team discovered that BaP’s mechanism of action is the same in acute myeloid leukemia (AML) and Burkitt lymphoma (BL) cells.

The findings have been published in Cancer Research.

BaP has been shown to prolong survival in early stage trials of elderly AML patients, when compared to standard palliative care. BaP has also been used alongside chemotherapy to successfully treat children with BL.

However, it was unclear whether BaP’s activity against these 2 very different malignancies was mediated by a common mechanism or by different effects in each cancer.

To gain some insight, Andrew Southam, PhD, of the University of Birmingham in the UK, and his colleagues investigated the drugs’ effects on the metabolism and chemical make-up of AML and BL cells.

They found that, in both cell types, BaP blocks stearoyl CoA desaturase, an enzyme crucial to the production of fatty acids, which cancer cells need to grow and multiply. The team also showed that BaP’s ability to deactivate stearoyl CoA desaturase was what prompted the cancer cells to die.

“Developing drugs to target the fatty-acid building blocks of cancer cells has been a promising area of research in recent years,” Dr Southam said. “It is very exciting we have identified these non-toxic drugs already sitting on pharmacy shelves.”

He and his colleagues believe these findings also open up the possibility that BaP could be used to treat other cancers that rely on high levels of stearoyl CoA desaturase to grow, including chronic lymphocytic leukemia and some types of non-Hodgkin lymphoma, as well as prostate, colon, and esophageal cancers.

“This drug combination shows real promise,” said Chris Bunce, PhD, also of the University of Birmingham.

“Affordable, effective, non-toxic treatments that extend survival, while offering a good quality of life, are in demand for almost all types of cancer.”

Micrograph showing BL

Image by Ed Uthman

Combining a cholesterol-lowering drug and a contraceptive steroid could be a safe, effective treatment for leukemias, lymphomas, and other malignancies, according to researchers.

Their work helps explain how this combination treatment, bezafibrate and medroxyprogesterone acetate (BaP), kills cancer cells.

The team discovered that BaP’s mechanism of action is the same in acute myeloid leukemia (AML) and Burkitt lymphoma (BL) cells.

The findings have been published in Cancer Research.

BaP has been shown to prolong survival in early stage trials of elderly AML patients, when compared to standard palliative care. BaP has also been used alongside chemotherapy to successfully treat children with BL.

However, it was unclear whether BaP’s activity against these 2 very different malignancies was mediated by a common mechanism or by different effects in each cancer.

To gain some insight, Andrew Southam, PhD, of the University of Birmingham in the UK, and his colleagues investigated the drugs’ effects on the metabolism and chemical make-up of AML and BL cells.

They found that, in both cell types, BaP blocks stearoyl CoA desaturase, an enzyme crucial to the production of fatty acids, which cancer cells need to grow and multiply. The team also showed that BaP’s ability to deactivate stearoyl CoA desaturase was what prompted the cancer cells to die.

“Developing drugs to target the fatty-acid building blocks of cancer cells has been a promising area of research in recent years,” Dr Southam said. “It is very exciting we have identified these non-toxic drugs already sitting on pharmacy shelves.”

He and his colleagues believe these findings also open up the possibility that BaP could be used to treat other cancers that rely on high levels of stearoyl CoA desaturase to grow, including chronic lymphocytic leukemia and some types of non-Hodgkin lymphoma, as well as prostate, colon, and esophageal cancers.

“This drug combination shows real promise,” said Chris Bunce, PhD, also of the University of Birmingham.

“Affordable, effective, non-toxic treatments that extend survival, while offering a good quality of life, are in demand for almost all types of cancer.”

Micrograph showing BL

Image by Ed Uthman

Combining a cholesterol-lowering drug and a contraceptive steroid could be a safe, effective treatment for leukemias, lymphomas, and other malignancies, according to researchers.

Their work helps explain how this combination treatment, bezafibrate and medroxyprogesterone acetate (BaP), kills cancer cells.

The team discovered that BaP’s mechanism of action is the same in acute myeloid leukemia (AML) and Burkitt lymphoma (BL) cells.

The findings have been published in Cancer Research.

BaP has been shown to prolong survival in early stage trials of elderly AML patients, when compared to standard palliative care. BaP has also been used alongside chemotherapy to successfully treat children with BL.

However, it was unclear whether BaP’s activity against these 2 very different malignancies was mediated by a common mechanism or by different effects in each cancer.

To gain some insight, Andrew Southam, PhD, of the University of Birmingham in the UK, and his colleagues investigated the drugs’ effects on the metabolism and chemical make-up of AML and BL cells.

They found that, in both cell types, BaP blocks stearoyl CoA desaturase, an enzyme crucial to the production of fatty acids, which cancer cells need to grow and multiply. The team also showed that BaP’s ability to deactivate stearoyl CoA desaturase was what prompted the cancer cells to die.

“Developing drugs to target the fatty-acid building blocks of cancer cells has been a promising area of research in recent years,” Dr Southam said. “It is very exciting we have identified these non-toxic drugs already sitting on pharmacy shelves.”

He and his colleagues believe these findings also open up the possibility that BaP could be used to treat other cancers that rely on high levels of stearoyl CoA desaturase to grow, including chronic lymphocytic leukemia and some types of non-Hodgkin lymphoma, as well as prostate, colon, and esophageal cancers.

“This drug combination shows real promise,” said Chris Bunce, PhD, also of the University of Birmingham.

“Affordable, effective, non-toxic treatments that extend survival, while offering a good quality of life, are in demand for almost all types of cancer.”

Micrograph showing AML

A few years ago, researchers discovered that inhibiting the protein BRD4 can treat acute myeloid leukemia (AML). However, the mechanism that explains how the protein works has remained a mystery.

Now, investigators have discovered the larger signaling pathway to which BRD4 belongs. The team said their discovery points to additional therapeutic targets for AML and other malignancies.

The group described this work in Molecular Cell.

BRD4: A retrospective

In 2011, Christopher Vakoc, MD, PhD, of Cold Spring Harbor Laboratory in Cold Spring Harbor, New York, and his colleagues identified potential drug targets for AML using RNA interference. Out of that screen came BRD4 and the realization that leukemia cells were “extremely sensitive” to inhibition of this protein.

In a bit of serendipity, drugs to inhibit BRD4 had just been developed for other purposes. Dr Vakoc and his colleagues tested these drugs and found that one in particular, JQ1, worked well against a mouse model of aggressive AML.

In the past few years, several groups have reported similar therapeutic results in mice using JQ1 and closely related drugs.

“It’s been very satisfying to see that other groups have independently validated our findings,” Dr Vakoc said.

Due to the evidence of their effectiveness in mice, inhibitors of BRD4 moved into clinical trials starting in 2013. Currently, there are 12 active clinical trials targeting BRD4 in leukemia and other cancers, including one sponsored by a company to which Dr Vakoc has licensed JQ1.

“Once we published the first paper in 2011, the main objective in our lab has been to understand why these drugs work,” Dr Vakoc said. “Knowing the mechanism of action of a drug is essential to making the drug better because there will likely be many generations of BRD4 inhibitors.”

JQ1 and BRD4: How they work

In the current study, Dr Vakoc and his colleagues discovered that BRD4 works very closely with transcription factors that bind to DNA and selectively control the activity of certain genes. The transcription factors control blood formation and essentially give blood cells their “identity.”

The researchers found that JQ1 can make leukemia cells shed their leukemia characteristics and differentiate into normal white blood cells. The team also identified an intermediary molecule called p300 between BRD4 and the leukemia-associated transcription factors.

Active areas of research in Dr Vakoc’s lab include exploring other players in the pathway, particularly the molecules that BRD4 controls, and learning more about the transcription factors.

“This new work is leading us to realize that transcription factors are the masters of the biological universe,” Dr Vakoc said. “Clearly, they are driving the cancer phenotype.”

Micrograph showing AML

A few years ago, researchers discovered that inhibiting the protein BRD4 can treat acute myeloid leukemia (AML). However, the mechanism that explains how the protein works has remained a mystery.

Now, investigators have discovered the larger signaling pathway to which BRD4 belongs. The team said their discovery points to additional therapeutic targets for AML and other malignancies.

The group described this work in Molecular Cell.

BRD4: A retrospective

In 2011, Christopher Vakoc, MD, PhD, of Cold Spring Harbor Laboratory in Cold Spring Harbor, New York, and his colleagues identified potential drug targets for AML using RNA interference. Out of that screen came BRD4 and the realization that leukemia cells were “extremely sensitive” to inhibition of this protein.

In a bit of serendipity, drugs to inhibit BRD4 had just been developed for other purposes. Dr Vakoc and his colleagues tested these drugs and found that one in particular, JQ1, worked well against a mouse model of aggressive AML.

In the past few years, several groups have reported similar therapeutic results in mice using JQ1 and closely related drugs.

“It’s been very satisfying to see that other groups have independently validated our findings,” Dr Vakoc said.

Due to the evidence of their effectiveness in mice, inhibitors of BRD4 moved into clinical trials starting in 2013. Currently, there are 12 active clinical trials targeting BRD4 in leukemia and other cancers, including one sponsored by a company to which Dr Vakoc has licensed JQ1.

“Once we published the first paper in 2011, the main objective in our lab has been to understand why these drugs work,” Dr Vakoc said. “Knowing the mechanism of action of a drug is essential to making the drug better because there will likely be many generations of BRD4 inhibitors.”

JQ1 and BRD4: How they work

In the current study, Dr Vakoc and his colleagues discovered that BRD4 works very closely with transcription factors that bind to DNA and selectively control the activity of certain genes. The transcription factors control blood formation and essentially give blood cells their “identity.”

The researchers found that JQ1 can make leukemia cells shed their leukemia characteristics and differentiate into normal white blood cells. The team also identified an intermediary molecule called p300 between BRD4 and the leukemia-associated transcription factors.

Active areas of research in Dr Vakoc’s lab include exploring other players in the pathway, particularly the molecules that BRD4 controls, and learning more about the transcription factors.

“This new work is leading us to realize that transcription factors are the masters of the biological universe,” Dr Vakoc said. “Clearly, they are driving the cancer phenotype.”

Micrograph showing AML

A few years ago, researchers discovered that inhibiting the protein BRD4 can treat acute myeloid leukemia (AML). However, the mechanism that explains how the protein works has remained a mystery.

Now, investigators have discovered the larger signaling pathway to which BRD4 belongs. The team said their discovery points to additional therapeutic targets for AML and other malignancies.

The group described this work in Molecular Cell.

BRD4: A retrospective

In 2011, Christopher Vakoc, MD, PhD, of Cold Spring Harbor Laboratory in Cold Spring Harbor, New York, and his colleagues identified potential drug targets for AML using RNA interference. Out of that screen came BRD4 and the realization that leukemia cells were “extremely sensitive” to inhibition of this protein.

In a bit of serendipity, drugs to inhibit BRD4 had just been developed for other purposes. Dr Vakoc and his colleagues tested these drugs and found that one in particular, JQ1, worked well against a mouse model of aggressive AML.

In the past few years, several groups have reported similar therapeutic results in mice using JQ1 and closely related drugs.

“It’s been very satisfying to see that other groups have independently validated our findings,” Dr Vakoc said.

Due to the evidence of their effectiveness in mice, inhibitors of BRD4 moved into clinical trials starting in 2013. Currently, there are 12 active clinical trials targeting BRD4 in leukemia and other cancers, including one sponsored by a company to which Dr Vakoc has licensed JQ1.

“Once we published the first paper in 2011, the main objective in our lab has been to understand why these drugs work,” Dr Vakoc said. “Knowing the mechanism of action of a drug is essential to making the drug better because there will likely be many generations of BRD4 inhibitors.”

JQ1 and BRD4: How they work

In the current study, Dr Vakoc and his colleagues discovered that BRD4 works very closely with transcription factors that bind to DNA and selectively control the activity of certain genes. The transcription factors control blood formation and essentially give blood cells their “identity.”

The researchers found that JQ1 can make leukemia cells shed their leukemia characteristics and differentiate into normal white blood cells. The team also identified an intermediary molecule called p300 between BRD4 and the leukemia-associated transcription factors.

Active areas of research in Dr Vakoc’s lab include exploring other players in the pathway, particularly the molecules that BRD4 controls, and learning more about the transcription factors.

“This new work is leading us to realize that transcription factors are the masters of the biological universe,” Dr Vakoc said. “Clearly, they are driving the cancer phenotype.”

Micrograph showing AML

Image by Lance Liotta

The US Food and Drug Administration (FDA) has granted orphan designation for GMI-1271 to treat acute myeloid leukemia (AML).

GMI-1271, an E-selectin antagonist, has shown promise in preclinical research and proven safe in a phase 1 trial of healthy volunteers, according to GlycoMimetics, Inc., the company developing the drug.

Now, the company is recruiting adults with AML in a phase 1/2 study to test GMI-1271 in combination with chemotherapy.

“Having the FDA designate GMI-1271 as an orphan drug for the treatment of AML is an important accomplishment for GlycoMimetics,” said Helen Thackray, MD, vice president of clinical development and chief medical officer at GlycoMimetics. “This is a significant regulatory milestone for our program.”

The FDA’s orphan drug designation program is designed to promote the development of drugs intended to treat diseases affecting fewer than 200,000 people in the US.

Orphan designation provides a drug’s developer with benefits such as a 7-year period of marketing exclusivity if the drug is approved, protocol assistance, the ability to apply for research funding, tax credits for certain research expenses, and regulatory fee waivers.

Research with GMI-1271

Preclinical research presented at ASH 2013 suggested that GMI-1271 was able to overcome chemotherapy resistance in AML cells in vitro. The drug also reduced the leukemic burden in mouse models of AML when given in combination with daunorubicin and cytarabine.

Murine research presented at ASH 2014 suggested that, by inhibiting E-selectin, GMI-1271 may increase leukemic stem cells’ sensitivity to chemotherapeutic drugs.

At the same meeting, researchers presented preclinical data on GMI-1271 as a treatment for chronic myeloid leukemia, multiple myeloma, and venous thromboembolism.

In November 2014, GlycoMimetics announced results of phase 1 trial of GMI-1271 in healthy volunteers. Twenty-eight adults were enrolled in cohorts to receive the drug at 3 dose levels.

The company said subjects tolerated GMI-1271 well, and pharmacokinetics were as predicted based on preclinical research.

A multicenter, phase 1/2 trial of GMI-1271 in combination with chemotherapy is now recruiting adult patients with AML.

Micrograph showing AML

Image by Lance Liotta

The US Food and Drug Administration (FDA) has granted orphan designation for GMI-1271 to treat acute myeloid leukemia (AML).

GMI-1271, an E-selectin antagonist, has shown promise in preclinical research and proven safe in a phase 1 trial of healthy volunteers, according to GlycoMimetics, Inc., the company developing the drug.

Now, the company is recruiting adults with AML in a phase 1/2 study to test GMI-1271 in combination with chemotherapy.

“Having the FDA designate GMI-1271 as an orphan drug for the treatment of AML is an important accomplishment for GlycoMimetics,” said Helen Thackray, MD, vice president of clinical development and chief medical officer at GlycoMimetics. “This is a significant regulatory milestone for our program.”

The FDA’s orphan drug designation program is designed to promote the development of drugs intended to treat diseases affecting fewer than 200,000 people in the US.

Orphan designation provides a drug’s developer with benefits such as a 7-year period of marketing exclusivity if the drug is approved, protocol assistance, the ability to apply for research funding, tax credits for certain research expenses, and regulatory fee waivers.

Research with GMI-1271

Preclinical research presented at ASH 2013 suggested that GMI-1271 was able to overcome chemotherapy resistance in AML cells in vitro. The drug also reduced the leukemic burden in mouse models of AML when given in combination with daunorubicin and cytarabine.

Murine research presented at ASH 2014 suggested that, by inhibiting E-selectin, GMI-1271 may increase leukemic stem cells’ sensitivity to chemotherapeutic drugs.

At the same meeting, researchers presented preclinical data on GMI-1271 as a treatment for chronic myeloid leukemia, multiple myeloma, and venous thromboembolism.

In November 2014, GlycoMimetics announced results of phase 1 trial of GMI-1271 in healthy volunteers. Twenty-eight adults were enrolled in cohorts to receive the drug at 3 dose levels.

The company said subjects tolerated GMI-1271 well, and pharmacokinetics were as predicted based on preclinical research.

A multicenter, phase 1/2 trial of GMI-1271 in combination with chemotherapy is now recruiting adult patients with AML.

Micrograph showing AML

Image by Lance Liotta

The US Food and Drug Administration (FDA) has granted orphan designation for GMI-1271 to treat acute myeloid leukemia (AML).

GMI-1271, an E-selectin antagonist, has shown promise in preclinical research and proven safe in a phase 1 trial of healthy volunteers, according to GlycoMimetics, Inc., the company developing the drug.

Now, the company is recruiting adults with AML in a phase 1/2 study to test GMI-1271 in combination with chemotherapy.

“Having the FDA designate GMI-1271 as an orphan drug for the treatment of AML is an important accomplishment for GlycoMimetics,” said Helen Thackray, MD, vice president of clinical development and chief medical officer at GlycoMimetics. “This is a significant regulatory milestone for our program.”

The FDA’s orphan drug designation program is designed to promote the development of drugs intended to treat diseases affecting fewer than 200,000 people in the US.

Orphan designation provides a drug’s developer with benefits such as a 7-year period of marketing exclusivity if the drug is approved, protocol assistance, the ability to apply for research funding, tax credits for certain research expenses, and regulatory fee waivers.

Research with GMI-1271

Preclinical research presented at ASH 2013 suggested that GMI-1271 was able to overcome chemotherapy resistance in AML cells in vitro. The drug also reduced the leukemic burden in mouse models of AML when given in combination with daunorubicin and cytarabine.

Murine research presented at ASH 2014 suggested that, by inhibiting E-selectin, GMI-1271 may increase leukemic stem cells’ sensitivity to chemotherapeutic drugs.

At the same meeting, researchers presented preclinical data on GMI-1271 as a treatment for chronic myeloid leukemia, multiple myeloma, and venous thromboembolism.

In November 2014, GlycoMimetics announced results of phase 1 trial of GMI-1271 in healthy volunteers. Twenty-eight adults were enrolled in cohorts to receive the drug at 3 dose levels.

The company said subjects tolerated GMI-1271 well, and pharmacokinetics were as predicted based on preclinical research.

A multicenter, phase 1/2 trial of GMI-1271 in combination with chemotherapy is now recruiting adult patients with AML.