Verona Pharma PLC (LON:VRP) saw more than a fifth wiped from its value after its lead drug, a potential treatment for chronic obstructive pulmonary disease (COPD), failed to meet the primary endpoint of a mid-stage clinical trial.

The three-day Phase II study saw COPD patients given either 1.5mg or 6.0mg of ensifentrine in combination with Stiolto Respimat – a commonly used maintenance treatment for COPD patients.

Boss still optimistic

Results from the trial showed that ensifentrine did not improve breathing by a “statistically significant” amount, although it was better than a placebo

“While we are disappointed that this exploratory Phase 2 study did not achieve statistical significance for its primary endpoint, these data give us clarity on the design, including dose and background therapy, for future long-term studies,” said chief executive Jan-Anders Karlsson.

“Having demonstrated in previous studies the potential of ensifentrine to deliver benefits to patients on no or single bronchodilator therapy, we believe that this short study continues to support our view that ensifentrine may also be of benefit to more severe COPD patients on dual and triple therapy, for whom there are few other treatment options.”

The market didn’t share the same sense of optimism, with the stock slipping 21% to 82.2p on Monday morning.