Amylyx wields axe as it pulls ALS drug from the market

Amylyx confirmed today that it will withdraw its amyotrophic lateral sclerosis (ALS) therapy Relyvrio/Albrioza from the market in the US and Canada, shortly after the drug failed a clinical trial.

The company said that it was stopping access to the drug for new patients immediately, while those already taking it would be able to continue on it via a free drug programme, after consultation with their doctors – a move that has garnered praise from across the biopharma industry.

Relyvrio (sodium phenylbutyrate/taurursodiol), which has a list price of $158,000 per year in the US and is also sold in Canada as Albrioza, generated sales of about $381 million last year and is Amylyx’s only commercial product. It missed all its objectives in the PHOENIX trial reported last month, designed to confirm its accelerated approval in 2022 based on the phase 2 CENTAUR study.

In a statement, Amylyx’s co-chief executives, Justin Klee and Joshua Cohen (pictured top), said: “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.”

Job losses coming

Faced with the loss of its only revenue generator, Amylyx said it would reduce its headcount by 70% to eke out its cash reserves into 2026 while it brings forward its clinical and preclinical pipeline. The company ended 2023 with cash reserves of $371 million.

That includes AMX0035 for Wolfram syndrome and progressive supranuclear palsy (PSP), which is based on the same active ingredients as Relyvrio, and follow-up ALS therapy AMX0114.

Data from the phase 2 HELIOS trial of AMX0035 in Wolfram syndrome – a genetic disorder that leads to diabetes, optic nerve atrophy, hearing loss, and neurodegeneration with no FDA-approved therapies – will be presented later this month, while the phase 3 ORION study in PSP is due to generate results in the middle of next year.

AMX0014, meanwhile, is a calpain-2-targeting antisense drug, in late preclinical development, with an initial clinical trial due to start before year-end.

“Our pipeline is supported by compelling clinical and preclinical science demonstrating the potential of AMX0035 and AMX0114 in neurodegenerative diseases,” said Amylyx’s chief medical officer, Camille Bedrosian.

The demise of Relyvrio is a big blow to the ALS patient community, as the drug was only the third to be approved by the FDA for the disease after Mitsubishi Tanabe’s Radicava (edaravone) and generic drug riluzole, sold as Rilutek by Sanofi.

It comes after the failure of two other drugs in late-stage clinical trials, Apellis’ pegcetacoplan and Cytokinetics’ resedemtiv, although there has been one bit of good news with the FDA approval last year of Biogen’s Qalsody (tofersen) for a genetic form of ALS associated with a mutation in the SOD1 gene.