Health Canada has rubber-stamped an experimental therapy to treat people with amyotrophic lateral sclerosis, also known as Lou Gehrig’s diseaseunder an accelerated approval program for drugs that show promise but lack data demonstrating their effectiveness, reports The New York Times. The conditional approval requires that the treatment’s developer, Amylyx Pharmaceuticals, provide further evidence that the treatment works, but it will be available in as soon as six weeks to private payers and possibly within several months to those seeking it under Canada’s public health system.  

The treatment, AMX0035 (marketed as Albrioza), is composed of two drugs—tauroursodeoxycholic acid and sodium phenylbutyrate—that protect nerve cells by blocking stress signals within mitochondria and protein-synthesizing organelles called endoplasmic reticula, according to ALS News Today.

The Times reports that, to date, the treatment’s effectiveness has been measured in a Phase 2 clinical trial involving 137 participants, as well as an open-label extension study, which followed 90 people from the original trial, including 34 people from the placebo group who began taking the drug combination after the Phase 2 study ended. People who’d been taking the therapy the longest postponed severe disease outcomes, including hospitalization, required assistance in breathing, or death for a median of 6.5 months compared to those in the placebo group. In addition, the Times reports that people receiving the treatment showed slower disease progression when functional losses such as walking, speaking, and swallowing were evaluated on a commonly used 48-point scale; specifically, people taking the drugs showed a 2.3-point lower decline in function compared to the placebo group.

See “New Drug Combo for ALS Slows Decline in Small Clinical Study

However, the US Food and Drug Administration (FDA) and its independent advisory committee aren’t convinced the data show a strong enough benefit to justify approving the treatment. While the FDA has an accelerated approval process similar to that of Health Canada’s, the Times reports that the US agency found in March that the available evidence fails to prove the therapy slows the disease’s progression or helps people with ALS live longer. While the advisory committee voted six to four against approving the treatment, the agency itself has yet to issue a final determination, instead extending its deadline to do so until September 29 while it reviews additional data, according to the Times.

G. Caleb Alexander, an epidemiologist at the Johns Hopkins Bloomberg School of Public Health who sits on the advisory committee and who voted against approving Albrioza, tells the Times that the FDA should wait to approve the therapy until results from a larger Phase 3 trial become available, which won’t be until 2024. But he adds that the drugs’ “approval in Canada could only further increase the pressure that the FDA faces to rule favorably and to approve the product.”

Calaneet Balas, the president and chief executive of the ALS Association, tells the Times, “We expect that Americans living with ALS will try to access Albrioza in Canada, just as we have heard reports of people trying to buy the ingredients on Amazon.”

In addition to patient advocacy groups such as the ALS Association pushing for the drug’s approval in the US, 38 doctors who treat people with ALS issued a letter last month calling on the FDA to swiftly approve it. The letter argued that people with ALS would significantly benefit from taking the drug combination, even if trial results seem incremental to some. “It can mean a difference between walking up the stairs or being restricted to a floor of your home. It can mean being able to feed yourself versus needing help to just cut your food. This means more time for our patients with the people they love,” the physicians write.