Spinal Muscular Atrophy
The TOPAZ Phase 2 proof of concept trial evaluated the safety and efficacy of apitegromab (SRK-015) in patients with Type 2 and Type 3 SMA.
The trial enrolled 58 patients between the ages of 2 and 21 in the U.S. and Europe across three distinct cohorts. All patients received apitegromab once every four weeks either as a monotherapy or in conjunction with an approved SMN upregulator treatment over a 12-month treatment period. The primary efficacy endpoints measure motor function through clinically meaningful outcome measures validated in SMA, such as the Hammersmith Functional Motor Scale Expanded (HFMSE) in non-ambulatory SMA and the Revised Hammersmith Scale (RHS) in ambulatory SMA.
A pre-planned interim analysis was conducted following a six-month treatment period, and positive proof-of-concept data were announced in October 2020. Top-line results for the full 12-month treatment period were announced in April 2021.
The results of TOPAZ informed the design of SAPPHIRE, a randomized, double-blind, placebo-controlled, phase 3 clinical trial. Approximately 156 patients aged 2-12 years old with non-ambulatory Type 2/3 SMA are anticipated to be enrolled in the main efficacy population of the study. Patients will receive either apitegromab or placebo every 4 weeks for 12 months, which will be added on top of background SMN treatment, either nusinersen or risdiplam.
Separately from the main efficacy population, an exploratory population of approximately 48 patients aged 13-21 years old with non-ambulatory Type 2/3 SMA will also be evaluated. Start-up activities for SAPPHIRE commenced in November 2021.
The DRAGON trial is investigating SRK-181, a selective inhibitor of TGFβ1 activation, in patients with locally advanced or metastatic solid tumors that have shown primary resistance to checkpoint inhibitor therapies. Part A was designed to assess safety and tolerability of SRK-181. With some results of Part A available, Part B dose expansion portion of the trial is now underway to evaluate SRK-181 in combination with an approved anti-PD-(L)1 therapy across multiple solid tumor cohorts to test proof of consent.
Patients seeking more information on potential clinical trials should contact their physician.