The FDA approvals of Biogen’s Spinraza (nusinersen) and Novartis’ gene therapy for spinal muscular atrophy (SMA), Zolgensma, were landmark events that brought to market the first disease-modifying therapies for this often devastating, genetic neuromuscular disease. They also form the basis of a fascinating, ongoing, real-world case study in how the natural course of a condition like SMA can change rapidly once effective treatments are introduced. Such changes present opportunities for additional therapies, including the creation of franchises centered on supportive treatments to address residual symptoms and other needs that may emerge in patients who live longer as a result of the stabilization of their disease.
The extent of such residual issues, however, is not yet known and will likely vary greatly with the type of SMA, which can range from severe to a relatively mild, adult-onset form. The real-world data for SMA patients in the face of the new disease-stabilizing therapies is as yet limited and will come into focus over time. But it is likely that this evolving SMA experience could become a blueprint for drug development and market access strategies for other progressive genetic neurological diseases and beyond.
In our recently published In Vivo article, available in full here, we examine challenges and opportunities in the field of SMA, including how new disease-modifying therapies are likely to change SMA’s course over time, based on a series of interviews with prominent experts. We also discuss the issues of market access, related to both newborn screening and diagnosis in older patients or those affected by milder forms of the disease. Pricing issues are also an important factor for consideration.
Novartis, Biogen and Roche are all aiming to establish disease-modifying SMA franchises, as well as supportive products such as therapeutics to bolster muscle strength. We discuss these and other product development efforts and conclude with a consideration of how the evolution of SMA treatment could become a blueprint for developing disease-modifying and supportive therapies in other neuromuscular and neurodegenerative conditions.