Biopharmaceutical firm Cytokinetics has reported findings obtained from the Phase II FORTITUDE-ALS clinical trial of reldesemtiv in patients with amyotrophic lateral sclerosis (ALS), a neurodegenerative disease.

The trial failed to demonstrate statistical significance for its primary endpoint of change in slow vital capacity (SVC) from baseline following 12 weeks of dosing.

Dose-response analyses for the secondary endpoint also revealed no statistical significance between the investigational drug and placebo arms.

However, data showed that all patients who received reldesemtiv declined less for SVC and ALSFRS-R, compared to those on placebo. Larger and clinically meaningful differences were observed over time.

The differences between the investigational drug and placebo in SVC and ALSFRS-R total score at 12 weeks were found to be evident at the follow-up of four weeks after the last dose of reldesemtiv.

“This Phase II trial of reldesemtiv demonstrated consistency of effect for doses, endpoints, and timepoints.”

Also, placebo and active treatment arms showed similar incidence of early treatment discontinuations, serious adverse events, and clinical adverse events.

The most common clinical adverse effects reported in the trial included fatigue, nausea, and headache.

During FORTITUDE-ALS, the primary reason for early termination for patients on reldesemtiv was deterioration in cystatin C based estimated glomerular filtration rate (eGFR), a renal function measure.

In the placebo group, the primary reason was progressive disease.

Cytokinetics Research and Development executive vice-president Fady Malik said: “While FORTITUDE-ALS did not meet the primary endpoint, we are encouraged by the results of the trial as they further validate the potential of skeletal muscle activation in treating patients battling ALS.

“This Phase II trial of reldesemtiv demonstrated consistency of effect for doses, endpoints, and timepoints and we believe the results support progression of reldesemtiv in further clinical trials toward potential registration.”

Being developed in alliance with Astellas, reldesemtiv is a fast skeletal muscle troponin activator (FSTA) intended to treat debilitating diseases and conditions related to skeletal muscle weakness and / or fatigue.

The double-blind, randomised, dose-ranging, placebo-controlled, parallel group FORTITUDE-ALS trial evaluated reldesemtiv in a total of 458 ALS patients across the US, Canada, Europe, and Australia.