Scholar Rock: New Data from Phase 2 Spinal Muscular Atrophy Trial

 Scholar Rock announced new data from the Phase 2 TOPAZ trial extension period evaluating patient outcomes at 36 months of treatment with apitegromab. These data showed that continued treatment with apitegromab over the extended treatment period was associated with substantial and sustained improvement in motor function, as well as improvements in patient-reported outcome measures in patients with nonambulatory Types 2 and 3 spinal muscular atrophy (SMA) receiving survival motor neuron (SMN)-targeted therapy. For the 36-month data, an observed case analysis was conducted, which pooled data for all nonambulatory patients (including those patients on 20 mg/kg of apitegromab for the full duration of the trial, and those who switched from 2 mg/kg to 20 mg/kg at various time intervals in year 2) and was based upon the available data.

These analyses exclude data for patients post scoliosis surgery. Improvement in Patient-Reported Outcomes Consistent with Improvements in Motor Function: Nonambulatory patients (ages 2-21) had improvements in PEDI-CAT (measure of activities of daily living) and PROMIS-Fatigue (a patient-reported outcome tool measuring fatigue) that were consistent and sustained at 36 months. The mean change in PEDI-CAT daily activity domain from baseline at 36 months was 2.2 (95% CI: –0.1, 4.5; N=17), indicating an improvement in the ability to perform daily activities.

The mean change in PROMIS-Fatigue from baseline at 36 months was –4.6 (95% CI: –8.7, –0.5; N=14), indicating a decline in fatigue. These improvements in PEDI-CAT and PROMIS-Fatigue were generally consistent with improvements in motor function across the 36 months of the study period. Consistent Safety Data: Treatment-emergent adverse events (TEAEs) at 36 months were consistent with previous reports at 12 and 24 months, with no new findings after an aggregate of 198 patient-years of exposure.

TEAEs were mostly mild-to-moderate in severity, and generally consistent with the underlying patient population and background therapy. The five most common TEAEs were headache, pyrexia, COVID-19, nasopharyngitis, and upper respiratory tract infection. No deaths or suspected unexpected serious adverse reactions or hypersensitivity reactions were observed with apitegromab at 36 months.

https://www.marketscreener.com/quote/stock/SCHOLAR-ROCK-HOLDING-CORP-43499888/news/Scholar-Rock-Announces-New-Data-from-the-Phase-2-TOPAZ-Trial-Extension-Period-Evaluating-Patient-Out-44244069/