Aldeyra Therapeutics, Inc. (NASDAQ:ALDX) (Aldeyra), a biotechnology company devoted to discovering and developing innovative therapies designed to treat immune-mediated diseases, today announced receipt of a Complete Response Letter (CRL) from the U.S. Food and Drug Administration (FDA) for the New Drug Application (NDA) of reproxalap, an investigational drug candidate, for the treatment of dry eye disease. The CRL stated that there is "a lack of substantial evidence consisting of adequate and well-controlled investigations … that the drug product will have the effect it purports or is represented to have under the conditions of use prescribed, recommended, or suggested in its proposed labeling" and that "the application has failed to demonstrate efficacy in adequate and well controlled studies in the treatment of signs and symptoms of dry eye disease." The letter also stated that the "inconsistency of study results raises serious concerns about the reliability and meaningfulness of the positive findings" and that the "totality of evidence from the completed clinical trials does not support the effectiveness of the product." Consistent with prior NDA reviews of reproxalap, no safety or manufacturing concerns were identified.

During the NDA review, label drafts were provided by the FDA in December 2025 and again in March 2026. Aldeyra does not believe that label negotiations were completed.

The FDA recommended that the reasons for failure in certain trials be explored, and that populations or certain conditions in which reproxalap may be effective be identified. The FDA did not recommend conducting additional trials or request submission of additional confirmatory evidence. As such, Aldeyra does not currently expect to pursue additional clinical trials, and intends to expeditiously request a Type A meeting to understand the actions needed for NDA approval. Per Prescription Drug User Fee Act (PDUFA) goals, the target Type A meeting date is within 30 days of receipt of the meeting request.