Insmed’s medicine didn’t just reduce exacerbations of a chronic lung disease in a phase 3 trial. The drug blew the primary endpoint out of the water with “very statistically significant” results, according to analysts.
Elsewhere in the ASPEN trial of brensocatib in non-cystic fibrosis bronchiectasis, the results were more muddled, according to a Tuesday press release.
Insmed’s shares more than doubled in value, rising from $22 at the previous close to $46 as the markets opened Tuesday morning.
The late-stage trial tested brensocatib against placebo in patients with the chronic lung disease bronchiectasis, which causes the airways to permanently widen. The primary analysis comes from 1,680 adult patients and 41 adolescents. Both doses of the therapy reduced the annualized rate of pulmonary exacerbations when compared to the placebo group.
Patients in the 10-mg group experienced a 21% reduction in exacerbations, for a p-value of p=0.0019, while those taking 25 mg saw a 19% reduction for a p-value of 0.0046.
Several key secondary endpoints were also met, including prolonged time to first pulmonary exacerbation and an increase in the odds of remaining exacerbation-free over 52 weeks.
However, the study did not meet the secondary goal of a change in baseline of post-bronchodilator forced expiratory volume in one second at Week 52 for the low dose. The therapy also did not reduce the annualized rate of severe pulmonary exacerbations for either dose.
Mizuho analysts were undeterred, however, noting the wide win on the primary goal for both doses that well cleared the prespecified—and very high—bar for success.
“Bigger picture, the positive outcome should provide a huge sigh of relief for investors (especially those who've been in the stock for some time), as we believe it helps to secure a more positive outlook on the company's future,” Mizuho’s team wrote Tuesday morning.
Had brensocatib been unsuccessful, Mizuho previously predicted that the company would have had to undergo significant restructuring.
Mizuho was also happy to see no “red flags” in the safety data. There were fewer treatment-emergent adverse events in the treatment group compared to placebo.
Insmed now plans to take the data to regulators in the fourth quarter, with a launch targeted for mid-2025.
Brensocatib is also in a phase 2 test for chronic rhinosinusitis without nasal polyps, and the company is planning to kick off a midstage trial for hidradenitis suppurativa this quarter.