Manufacturer to pull controversial ALS drug off the market after failed clinical trial

The maker of a drug to treat Lou Gehrig’s disease, or ALS, says it will withdraw the medication from the market after it recently failed a large clinical trial. 

Amylyx Pharmaceuticals said it will halt sales and marketing of Relyvrio in the United States and Canada, and it will no longer be available for new patients as of Thursday. 

“While this is a difficult moment for the ALS community, we reached this path forward in partnership with the stakeholders who will be impacted and in line with our steadfast commitment to people living with ALS and other neurodegenerative diseases,” Amylyx co-CEOs Joshua Cohen and Justin Klee said in a statement. 

The move comes after the company announced last month that a trial of more than 650 people showed Relyvrio failed to outperform a placebo in slowing the progression of ALS, and it showed no benefit to patients. The drug also failed to show improvement on any secondary endpoints in the trial, such as muscle strength.  

Patients already receiving the drug who wish to continue will be able to enroll in a program to receive it for free, the company said.  

The removal is a blow to ALS patients, who have few treatments available for the progressively debilitating disease. Once ALS starts, it always progresses, and most people with the disease eventually lose the ability to walk, dress, write, speak, swallow and breathe. The average survival time is three years, though some people live longer.  

The Food and Drug Administration (FDA) approved Relyvrio in 2022, based on data from a small trial that showed it moderately slowed the progression of ALS. The approval was contentious, and an outside expert advisory panel initially voted against the drug after expressing concerns over the data from such a small trial.  

But the panel later backed the drug after hearing from patients and ALS advocates during a follow-up public hearing. FDA ultimately approved the drug, and although the agency said there was uncertainty about its effectiveness, it was deemed acceptable given the dire need for any ALS therapy. 

The agency typically requires two large-scale Phase 3 studies before deciding on approval, each of which typically enroll several hundred to around 3,000 people. The data for Relyvrio came from one Phase 2 trial in which 137 patients took either the drug or a placebo.

The company was already in the process of conducting the larger trial, and even though it wasn’t needed once the drug got full FDA approval, the CEOs publicly promised that they would withdraw the drug if further testing failed to show a benefit. 

Amylyx faced criticism when Relyvrio first hit the market for charging nearly $160,000. Only about 4,000 patients in the United States have received the treatment since it was approved.