GSK ended development of its chronic cough drug camlipixant after Phase 3 trials showed limited efficacy. The 50 mg dose met its primary endpoint at 12 weeks in one study but failed at 24 weeks in another. Shares fell 2 percent as the setback removes a potential blockbuster from the pipeline.
GSK ended development of its chronic cough drug camlipixant after Phase 3 trials showed limited efficacy, sending shares down 2 percent to 1,916 pence.
"The aggregate data point to limited efficacy that is unlikely to transform patient care," GSK said in a statement Friday.
In the Calm-1 trial, the 50 mg twice-daily dose of camlipixant met its primary goal of reducing 24-hour cough frequency versus placebo at 12 weeks. But the same dose failed to reach statistical significance on that measure at 24 weeks in the Calm-2 study, and the low dose missed the bar in both trials. Key secondary endpoints also fell short across both studies.
The failure removes a potential blockbuster from GSK's pipeline that the company had forecast could generate peak sales above 2.5 billion pounds ($3.4 billion). The drugmaker acquired camlipixant through its $2 billion purchase of Bellus Health in 2023, betting that the P2X3 receptor antagonist could avoid the taste-related side effects that derailed Merck & Co.'s rival candidate gefapixant in the U.S.
GSK said treatment-related adverse events linked to camlipixant were comparable to placebo in both incidence and severity, confirming the drug's improved selectivity for P2X3 over P2X2 receptors present in taste buds. However, the efficacy data across the two studies did not support continued investment in the indication.
The setback complicates GSK's path to its 2031 revenue target of 40 billion pounds ($53.7 billion). Guggenheim Securities analysts had forecast 2031 sales of 35.9 billion pounds ($48.2 billion) even before the camlipixant disappointment, describing the drug's readout in May as "the key potential catalyst to drive mid- to long-term revenue upgrades this year."
A Phase 2b study of camlipixant in adults with irritable bowel syndrome with diarrhea and mixed bowel habits will continue, with a primary completion date of March 2027, according to the federal trials database.
The pipeline setback leaves GSK without a near-term respiratory growth driver and raises questions about its ability to close the gap to its 2031 revenue target. Investors will watch for updates on GSK's broader respiratory pipeline, including any plans to advance alternative candidates in chronic cough.
This article is for informational purposes only and does not constitute investment advice.
