Aldeyra Therapeutics Inc. (NASDAQ:ALDX) said it has received a Complete Response Letter from the U.S. Food and Drug Administration rejecting its New Drug Application for reproxalap, a proposed treatment for dry eye disease.
According to the FDA, there was “a lack of substantial evidence consisting of adequate and well-controlled investigations” demonstrating that the therapy would be effective under the proposed conditions of use. The agency added that the application “failed to demonstrate efficacy in adequate and well controlled studies in the treatment of signs and symptoms of dry eye disease.”
Regulators pointed to “inconsistency of study results,” which raised “serious concerns about the reliability and meaningfulness of the positive findings.” As a result, the FDA concluded that “the totality of evidence from the completed clinical trials does not support the effectiveness of the product.”
The agency did not identify any safety or manufacturing issues in its review, in line with earlier assessments of reproxalap. Aldeyra noted that the FDA had provided draft labeling in December 2025 and again in March 2026, although final label negotiations were not completed.
The FDA suggested that the company investigate the causes behind the unsuccessful trials and determine whether specific patient groups might benefit from reproxalap. However, the agency did not recommend conducting additional clinical studies or submitting further confirmatory evidence.
Aldeyra said it does not currently intend to launch new clinical trials for the drug and plans to request a Type A meeting with the FDA to clarify what steps may be required to move the application forward. Under Prescription Drug User Fee Act guidelines, the meeting is expected to take place within 30 days of the request.
As of December 31, 2025, the company reported approximately $70 million in cash, cash equivalents and marketable securities, which it said should be sufficient to fund operations through 2028.
Based in Lexington, Massachusetts, Aldeyra Therapeutics focuses on developing treatments for immune-mediated conditions. Its pipeline includes RASP modulators as well as ADX-2191, a therapy being developed for retinal diseases.