Roche Holding AG announced new two-year data from the JEWELFISH study evaluating Evrysdi® (risdiplam) in people with Type 1, 2 or 3 SMA aged 6 months to 60 years at time of enrolment. Patients had been previously treated with other approved or investigational SMA-targeting therapies, including nusinersen (Spinraza(R)) or onasemnogene abeparvovec (Zolgensma(R)). Data showed Evrysdi improved or maintained motor function and led to rapid increases in SMN protein levels which were sustained after 2-years of treatment.

These data will be presented at the 27thWorld Muscle Society (WMS) congress, 11-15 October 2022. The JEWELFISH study enrolled the broadest and most diverse patient population ever studied in an SMA trial. Of the 174 people enrolled, 36% (n=63) were adults, 63% (n=105) had a Hammersmith Functional Motor Scale Expanded (HFMSE) score of less than 10 at baseline, meaning their disease was very severe, and 83% (n=139) had scoliosis.

44% (n=76) of those enrolled had previously been treated with nusinersen (Spinraza), 41% (n=71) with olesoxime*, 8% (n=14) with onasemnogene abeparvovec (Zolgensma) and 7% (n=13) with RG7800. People with SMA are unable to produce enough survival motor neuron (SMN) protein, leading to debilitating and potentially fatal muscle weakness. The study showed Evrysdi led to a two-fold increase in median SMN protein levels versus baseline after 4 weeks of treatment in all patient groups, irrespective of previous treatment.

The SMN protein levels achieved after 4 weeks of treatment were maintained for over two years. Observed through exploratory efficacy endpoints, the study also suggests maintenance of motor function was sustained at two-years of treatment as measured by change from baseline in Motor Function Measure 32 (MFM-32), Revised Upper Limb Module (RULM) and HFMSE total scores compared to the natural history of SMA in untreated patients. A recent survey conducted by patient advocacy group SMA Europe, more than 96% of people with SMA viewed disease stabilization as progress in terms of their expectations of treatment.

The overall adverse event (AE) and serious adverse event (SAE) profiles observed with Evrysdi treatment in JEWELFISH were reflective of underlying disease. The rate of AEs decreased by more than 50% between the first and second 6-month period, and then remained stable thereafter. The rate of SAEs, including pneumonia, decreased throughout the 24-month period, with a total reduction of more than 50% by the second year.

The most common AEs (reported in = 12% of all patients:n=173) were pyrexia (24%), upper respiratory tract infection (21%), headache (18%), nasopharyngitis (16%), diarrhoea (14%), nausea (13%) and cough (12%). The most common SAEs (reported in less than >2% of all patients) were pneumonia (3%) respiratory failure (2%), respiratory distress (2%), lower respiratory tract infection (2%) and upper respiratory tract infection (2%). The most common AEs/SAEs were consistent with those observed in treatment-naïve patients in other three trials.

Low rates of discontinuation from the study were observed, with a 5% rate per year over the 24-month period.