Insmed claims the phase III study demonstrated the still-experimental Arikace was just as effective as currently approved Novartis' (NVS - Get Report) TOBI in treating bacterial lung infections afflicting cystic fibrosis patients. The company issued a press release declaring Arikace's success last July and promised to present actual data from the phase III study at a later date.
Those Arikace data were finally published this weekend at the North American Cystic Fibrosis conference but they don't exactly support Insmed's claims -- unless you're willing to accept some dodgy analysis and ignore missing data.
Insmed was unable to discuss the Arikace phase III results because the company was in a self-imposed quiet period ahead of third-quarter financial results on Nov. 5, according to a company spokesperson. Why the company chose to publicize the Arikace phase III results during its quiet period but not answer questions about the data was not explained.Let's dig into the Arikace study results. You can download a poster presentation of the data from Insmed's web site. First, take a look at this diagram pulled from the poster. It shows how patients were enrolled and randomized into the study. Of the 302 cystic fibrosis patients randomized, 148 were treated with LAI, which is the scientific name for Arikace. The other 146 patients were treated with TOBI. This comprises the modified intent-to-treat patient population (mITT) -- defined as all patients who received at least one dose of study drug. The set of boxes underneath discloses the "per protocol" patient population, which is not defined explicitly anywhere on the poster but seems to exclude patients who discontinued the study for some reason. There are 129 Arikace and 137 TOBI patients in the per protocol group, or 28 fewer patients than in the mITT group.