Cytokinetics will stop further testing of its experimental amyotrophic lateral sclerosis drug after an early look at the data found it was unlikely to succeed. The result comes four years after the Cytokinetics drug flunked its mid-stage test.

The interim analysis of the Phase 3 clinical trial was planned, triggered by enrollment in the pivotal test of the drug, reldesemtiv. Cytokinetics said Friday that the independent data monitoring committee reviewed unblinded data. On the main goal of showing a change from baseline at 24 weeks, the committee “found no evidence of effect in patients treated with reldesemtiv relative to placebo,” Cytokinetics said in its announcement.

Reldesemtiv is a small molecule designed to lead to an increase in the contractility of skeletal muscles that are weakened by ALS. The drug is a twice-daily pill. In 2019, Cytokinetics reported clinical data showing the drug failed to meet either the primary or secondary goals of a Phase 2 study. This placebo-controlled study enrolled 458 patients who were assessed after 12 weeks.

Despite the Phase 2 failure, Cytokinetics believed it could achieve better results by controlling for slow-progressing patients in the placebo arm. Cytokinetics proceeded with the Phase 3 study, which had a targeted enrollment of 555 patients who would be evaluated at 24 weeks.

Those who completed the Phase 3 study were invited to continue receiving the drug in 48-week open-label extension study. Given the futility of the Phase 3 study, Cytokinetics said that the extension study will also end. The full data from the Phase 3 program are still being analyzed and will be presented at an upcoming medical meeting, the company said.

“Cytokinetics has been committed to the ALS community for more than a decade and recognizes the urgency to bring new potential medicines to the forefront for this grievous disease,” Cytokinetics CEO Robert Blum said in a prepared statement. “In the coming months, we will assess next steps relating to our neuromuscular development programs.”

Cytokinetics’s late clinical-stage pipeline now consists of aficamten for obstructive hypertrophic cardiomyopathy. Last month, the FDA rejected another Cytokinetics heart drug, omecamtiv mecarbil, and told the company it needed to conduct another clinical trail to generate more data. Cytokinetics said it would not run that study and would instead turn its focus to aficamten. According to a corporate presentation earlier this month, Cytokinetics’s cash position at the end of 2022 was $830 million, which the company estimated would be enough to last for two years.

Public domain image by Flickr user Berkshire Community College Bioscience Image Library