Ra Pharmaceuticals has reported positive top-line results from a Phase II clinical trial assessing zilucoplan for the treatment of generalized myasthenia gravis (gMG), a chronic, autoimmune, neuromuscular disease characterised by weakness of skeletal muscles.
The trial saw 44 patients in the US and Canada randomised in a 1:1:1 ratio to receive daily SC doses of 0.1mg/kg of zilucoplan, 0.3mg/kg of zilucoplan, or placebo.
Results showed that patients treated with both the doses of zilucoplan achieved the trial’s pre-specified primary efficacy endpoint of change from baseline to week 12 in the Quantitative Myasthenia Gravis (QMG) score.
It was also found that daily subcutaneous (SC) dose of zilucoplan 0.3mg/kg witnessed a mean reduction from baseline of 6.0 points in the QMG score, and a mean reduction from baseline of 3.4 points in the MG Activities of Daily Living (MG-ADL) score.
Patients treated with a 0.3mg/kg dose of zilucoplan did not require any rescue therapy.
The data also showed that treatment with zilucoplan had a favourable safety and tolerability profile, similar to that of previous Phase I and Phase II studies.
The majority of adverse events (AEs) were reported as mild with no serious AEs observed related to zilucoplan.
Ra Pharmaceuticals founder and CEO Doug Treco said: “Designed for subcutaneous self-administration, zilucoplan offers convenience and accessibility, giving it the potential to bring C5 inhibition to the forefront of the treatment paradigm for gMG.
“We look forward to meeting with regulators to review our Phase II data and the design of our planned Phase III programme with the ultimate goal of transforming the lives of thousands of patients with this disease.”
The Phase II trial was conducted in a multi-centre, randomised, double-blind, placebo-controlled setting.
It evaluated the safety, tolerability, and preliminary efficacy of zilucoplan in patients with gMG, regardless of prior therapies.