Inotek tanks after placebo beats drug in glaucoma phase 3

A phase 3 glaucoma trial of Inotek Pharmaceuticals’ trabodenoson has missed its primary endpoint. The failure of the drug to beat placebo in terms of cutting intraocular pressure has thrown the future of the monotherapy program into doubt—and wiped more than 60% off Inotek’s share price in premarket trading.

Inotek compared the intraocular pressure of participants in the three treatment arms of the study to the placebo cohort at 12 time points throughout the 12-week trial. To hit the primary endpoint, trabodenoson needed to beat placebo at all 12 time points, something it failed to achieve.

The Lexington, MA-based drug developer is pinning the poor performance on lower-than-expected intraocular pressures among the placebo cohort. Specifically, when investigators took the first of each day’s readings at 8am the levels were down on those seen in the placebo cohort of the phase 2. More importantly, levels were similar to those seen in the trabodenoson arms of the phase 3.

In its search for causes for optimism, Inotek focused in on the 6% dose cohort. This 61-subject arm bested the 62-patient placebo group against some secondary endpoints. Inotek will cling to the hope offered by those data points as it heads toward a readout on a trial of trabodenoson in combination with latanoprost.

“Looking ahead, 2017 is an important year for the trabodenoson development program. We will wait for the full results from MATrX-1 to better understand the behavior of the placebo arm. We look forward to the results of the FDC phase 2 trial, which is substantially enrolled and for which we expect to report top-line data mid-year,” Inotek CEO David Southwell said in a statement.