The RESCUE-ALS trial (NCT04098406) enrolled 45 people with early-onset ALS, who were assigned randomly to take CNM-Au8 (30 mg/day) or a placebo for 36 weeks (about nine months). Participants then had the option to enter an open-label extension study in which all were given CNM-Au8. Results were presented in November 2021.
It's a phase II trial, which means it was designed to assess how well the drug works, as well as to continue Phase I safety assessments in a larger group of volunteers and patients.
The trial, did not meet its primary and a key secondary goal after 36 weeks of treatment: higher Motor Unit Number Index (MUNIX) scores — which measure the number, function, and health of motor neurons — and greater forced vital capacity (FVC), a measure of lung health. However, a trend toward better MUNIX scores was evident at 12 weeks among patients taking CNM-Au8.
In addition, quality of life at week 36 was significantly better in patients taking the investigational therapy, and there was evidence of benefit in long-term survival.
Over the eight-month trial, the therapy was also found to be relatively well-tolerated with no reported life threatening adverse events related to treatment.
It was followed by an open label trial. The data has accumulated and some new results of this open label trial were presented at ENCALS (2022 European Network to Cure ALS).
One poster (a low cost way to present results in scientific conferences) suggests that survival was improved by 24 weeks. Yet the phrasing is not very clear, it tells that early and continuous treatment with CNM-Au8 reduced mortality risk by 62% compared to delaying treatment. In one case one knows they can live longer, in the other case one can expect to be in the lucky people who would not die early.
A second poster is less bold, but clearly shows that quality of life was better with CNM-Au8 tha with placebo nearly one year after the start of the treatment. A third one reiterates that quality of life was better with CNM-Au8.
An ongoing platform clinical trial called HEALEY (NCT04297683) is testing the effectiveness of CNM-Au8 alongside several other potential ALS therapies. Results are expected later this year.
While all those good results are welcomed, one should reminds itself that in the world of biotechs it is common practice to make excessive announcements in order to attract investors. Here what could refrain enthusiasm is the lack of scientific publications on CNM-Au8, except those posters. Posters are usually presented by students, not by professional scientists.
Clene Nanomedicine claims that CNM-Au8 is a catalytic gold nanoparticule, which probably means it accelerates metabolic reactions. Usually nanoparticles are used to vehicle a drug, for example mRNA in COVID vaccines. So far CNM-Au8 has been demonstrated to be an efficient catalyst for metabolic energy reactions, converting the energetic metabolite nicotinamide adenine dinucleotide hydride (NADH) into NAD+ in proof-of-principle cell-free assays.
It's not clear what makes CNM-Au8 so successful in ALS. There is no publications on animal models of ALS. One can wonder why there is no more regulatory supervision on the organization of new clinical trials.
Let's hope these good results it will trigger more and more opened research in the area of nanoparticles for ALS.