Biogen recently announced the first SMA (spinal muscular atrophy) patient treated in a study Phase IV RESPOND that will evaluate the efficacy and safety of Spinraza (nusinersen) in patients with a suboptimal clinical response to Novartis’ Zolgensma (onasemnogene abeparvovec). Spinraza is expected to continue maintaining a strong position in the SMA market primarily due to its first-to-market feature, as well as its familiarity with patients and physicians, says GlobalData, a leading data and analytics company.

Alessio Brunello, Managing Pharma Analyst at GlobalData, comments: “Until the Food and Drug Administration (FDA) approval of Zolgensma in May 2019, Biogen’s Spinraza was the only approved treatment for SMA patients. Zolgensma is expected to play a pivotal role in the treatment landscape for SMA, however, the high price associated with this one-off therapy means that the company is facing reimbursement challenges in the seven major markets (*7MM).”

While Zolgensma’s approval expands the number of treatment options for SMA, there is still scope for other treatment options that can offer benefits, such as a favorable route of administration or one that can help improve muscle functions in SMA patients.

Key opinion leaders (KOLs) interviewed by GlobalData agree that the outcomes with Spinraza are favorable both for the patients and their families. However, there are also significant clinical and environmental challenges that continue to hinder the wider adoption of this therapy in certain settings.

Brunello continues: “Clinical challenges include the need for a lumbar puncture (LP) each time Spinraza needs to be administered via an intrathecal route. This requires institutional infrastructure and resources for the procedure to be carried out and for post-procedural monitoring of patients. Also, patients who have undergone spinal fusion procedures for associated spinal deformity have additional difficulty with undergoing an LP, a procedure which could put such patients at a greater risk of injury.”

In an effort to address this issue, companies such as Novartis and Roche are developing therapies that are proposed to have a similar mechanism of action (MOA) as Spinraza, but are intended to be administered via an oral route. Roche’s Evrysdi (risdiplam) was approved by FDA in July 2020, however, it will face challenges to erode Spinraza’s SMA market share despite convenient oral dosing due to safety concerns and lack of long-term data. Novartis’ branaplam is currently in Phase II of development in the US and EU and is expected to launch in the US in 2024.

The challenge posed by use of Spinraza, in particular that represented by the chronic nature of the treatment, were expected to be partially offset by Novartis’ gene therapy Zolgensma, which received FDA approval in May 2019 for use in pediatric patients less than two years of age with SMA.

Brunello adds: “While the prospect of a one-time gene therapy is exciting for patients and physicians, the lack of long-term safety and efficacy data of gene therapies and its price hindered Zolgensma’s immediate uptake in the market.”

7MM = US, 5EU (UK, Germany, France, Italy and Spain) and Japan