An experimental weight loss drug from Skye Bioscience failed a mid-stage clinical trial, wiping out most of the San Diego biotechnology company’s market value.
Skye said Monday its therapy, an obesity medicine targeting a kind of cannabinoid receptor, didn’t significantly lower weight loss compared to a placebo after 26 weeks of treatment. Patients who received Skye’s drug, nimacimab, achieved only 1.5% weight loss, compared to less than 0.3% for placebo recipients. In a statement, Skye blamed the findings on the dose it chose for the study, arguing an analysis found that a 200 milligram weekly injection is “suboptimal as a monotherapy.”
Nimacimab fared better when paired with semaglutide, the active ingredient in Novo Nordisk’s Wegovy, and tested against semaglutide alone. In that study cohort, patients on the combination lost just over 13% of their body weight, compared to more than 10% for those only on semaglutide. Skye said the findings support the potential for future studies evaluating combinations of nimacimab and other so-called incretin-based therapies widely used for weight loss.
Skye added that its drug demonstrated “placebo-like tolerability,” with no increase in gastrointestinal problems observed when combined with semaglutide. There also wasn’t any spike in psychiatric side effects with nimacimab — a concern with drugs of its kind.
In a statement provided by Skye, Louis Aronne, a company advisor and the past president of the nonprofit organization The Obesity Society, described the study results as the first evidence that drugs like nimacimab “can drive meaningful additional weight loss” beyond incretin therapies alone.
Skye Chief Medical Officer Puneet Arora noted, too, how the drug’s effects may have been limited by “lower-than-expected drug exposure,” which could inform the company’s strategy going forward. Skye will evaluate the data to determine next steps, including a potential “follow-on” Phase 2 study.
Nonetheless, company shares plummeted by nearly two-thirds, to less than $2 apiece, in early Monday trading.
Skye is one of many companies aiming to improve upon popular weight loss drugs like Wegovy with an additive therapy that might boost their effects or address limitations. The method it’s pursuing involves blocking “CB1,” a cannabinoid receptor that regulates appetite.
That concept hasn’t yet led to clinical success. Last September, a CB1-inhibiting drug from Novo Nordisk didn’t meet expectations for weight loss, leading the company to say “further work” was needed to optimize dosing. Still, some analysts expressed optimism following Novo’s readout. In a research note last month, William Blair’s Andy Hsieh wrote that the approach appeared to spur weight loss with a lower degree of gastrointestinal side effects and retention of muscle mass — another weakness of incretin therapies.
According to Hsieh, Skye executives had been hoping the nimacimab-Wegovy combination would induce weight loss that was 5 to 8 percentage points better than Wegovy alone.
