Collating long-term clinical data will contribute to an increased understanding of the safety profile of zilucoplan in generalized myasthenia gravis (gMG).
To evaluate the safety and efficacy of zilucoplan in an interim analysis of RAISE-XT (NCT04225871).
RAISE-XT, a Phase 3, multicenter, open-label extension study, recruited patients with gMG who participated in randomized Phase 2 (NCT03315130) and Phase 3 (NCT04115293) zilucoplan studies. All patients self-administered daily subcutaneous injections of 0.3 mg/kg zilucoplan. Primary outcome was incidence of treatment-emergent adverse events (TEAEs). Key secondary outcomes included Myasthenia Gravis Activities of Daily Living (MG-ADL) score.
199 patients enrolled in RAISE-XT; 104 continued zilucoplan from their qualifying study (zilucoplan group) and 95 switched to zilucoplan from placebo (placebo-switch group). Median exposure at data cut-off was 253.0 (range 29–1434) days. 169 (84.9%) patients experienced a TEAE; 46 (23.1%) patients experienced a serious TEAE. Most common TEAEs were headache and worsening of MG, both in 33 (16.6%) patients. At extension study Week 12, after 24 weeks of zilucoplan, the zilucoplan group achieved a least squares mean change in MG-ADL score from double-blind study baseline of −6.30 (95% CI: −7.44, −5.15). MG-ADL reduction from baseline for the placebo-switch group, after 12 weeks of zilucoplan, was −6.32 (95% CI: −8.00, −4.65).
In this interim analysis of RAISE-XT, zilucoplan demonstrated a favorable long-term safety profile. Efficacy in patients who had previously received zilucoplan continued to improve and was demonstrated for those who switched from placebo. The study is ongoing. Funding: UCB Pharma. These data were previously presented at the MGFA Scientific Session at AANEM, September 21–24, 2022.