Tiny Aldeyra’s eye drug misses primary endpoint in phase 2

A phase 2b trial of Aldeyra Therapeutics’ allergic conjunctivitis candidate ADX-102 has missed its primary endpoint. But the tiny biotech tried to brush off the setback, pointing to other aspects of the data to support its desire to advance the ophthalmic solution into a late-phase trial.

Investigators enrolled 154 patients with allergic conjunctivitis in the trial and randomized them to receive one of two dosages of aldehyde trap ADX-102 or a placebo. The trial set out to assess whether Aldeyra’s experimental drug could elicit a one point improvement over placebo on a scale of eye itching. For the study to hit its primary endpoint, the data had to link the treatment to such an improvement and a statistically-significant gain over the placebo.

The trial only met one of these requirements. While the trial showed higher, 0.5% dose of ADX-102 was statistically superior to the control, it failed to record a one point or more improvement on the zero-to-four patient-reported rating scale. That resulted in the study failing to meet its primary endpoint.

Despite the failure, Aldeyra found a silver lining it sees as justifying continued development in the indication.

“While the one-point improvement relative to control component of the primary endpoint was not met, the threshold was approached in seasonal allergy patients, with peak changes of 0.8, and was exceeded on a percent change basis in this population 30 to 60 minutes after allergen challenge, which we believe represents a novel activity profile that addresses late phase inflammation generally not affected by antihistamines,” Aldeyra CEO Todd Brady, M.D., Ph.D. said in a statement.

Buoyed by that upbeat interpretation of the data, Aldeyra is already looking beyond the upcoming end of phase 2 meeting with the FDA to a late-stage study. Aldeyra had $19 million in cash and $12 million in marketable securities at the end of March, since when it has moved to add up to $20 million to its bank balance through a stock sale agreement with Cantor Fitzgerald.

The company’s ability to attract investment rests largely on ADX-102, which it is developing in multiple indications characterized by aldehyde toxicity. Aldeyra recently started a phase 3 trial of the drug in patients with non-infectious anterior-uveitis and a phase 2 study in subjects with dry eye syndrome. And it has previously trialled a cream formulation of the aldehyde trap to treat skin disorders associated with Sjögren-Larsson syndrome.

Shares in Aldeyra fell 19% in premarket trading.