BOSTON – Some of the most influential clinical research reports coming out of the annual meeting of the American Academy of Neurology raise questions on how neurologists will strike a balance between the improved efficacy and safety of drugs in new therapeutic classes and their affordability for patients.
Natalia Rost, MD, vice chair of the AAN Science Committee, discussed phase III clinical trials (ARISE and STRIVE) in episodic migraine with erenumab, an investigational humanized monoclonal antibody against calcitonin gene-related peptide receptor; phase III clinical trials (ENDEAR and CHERISH) of the antisense oligonucleotide drug nusinersen (Spinraza) that was approved by the Food and Drug Administration for spinal muscular atrophy in late 2016; as well as phase III trials of a pharmaceutical-grade extract of the cannabis-derived compound cannabidiol in patients with Dravet syndrome and Lennox-Gastaut syndrome.
Erenumab and nusinersen are “disease-specific targeted biologics” that have been developed over decades to target a specific disease pathway, and hence translate into high prices, Dr. Rost said in a video interview at the meeting.
“How you value the cost of a drug against improvement in a physiological outcome is very difficult to measure,” she noted, for relatively small gains in reducing migraine days per month and improvements in functional outcome and disability against placebo.
But this calculation is different with the potentially lifesaving effects of nusinersen for spinal muscular atrophy patients, in which “we’re not talking about days of improvement, we’re talking about days of life,” said Dr. Rost, director of acute stroke services at Massachusetts General Hospital, Boston. “And so that becomes an ethical dilemma in terms of the cost of administration, who is paying for the drug, and how this is covered. Whom do you offer treatment to?”
The development of cannabidiol as a potential adjunctive treatment for Dravet and Lennox-Gastaut syndromes is a welcome addition to the armamentarium against these conditions, Dr. Rost added, because it offers an alternative to the unregulated use of herbal medications and supplements – particularly cannabis in its various forms – that patients ask about but are difficult to dose consistently and to ensure a pharmaceutical-grade level of purity.