Aldeyra Therapeutics, Inc. announced receipt of a Complete Response Letter from the U.S. Food and Drug Administration (FDA) for the 505(b)(2) Although no safety or manufacturing issues with ADX-2191 were identified, the FDA stated that there was a "lack of substantial evidence of effectiveness" due to a lack of adequate and well-controlled investigations" in the literature-based NDA submission. Based on prior discussions with the FDA, Aldeyra did not conduct any clinical trials of ADX-2191 in PVRL. PVRL is a rare, high-grade, aggressive cancer, with a median survival of less than five years.(1) Methotrexate, the combined intravitreal injection of which is the standard of care for the treatment of PVRL, is currently in shortage, per the FDA Drug Shortages database.

Top-line results from a Phase 2 clinical trial of ADX-2 191 in PVRL are expected to be announced in June of 2023. Additionally, Aldeyra plans to conduct a Type C meeting with the FDA in the second half of 2023 to discuss the completion of clinical development of ADX-2191 for the prevention of proliferative vitreoretinopathy. All of Aldeyra's development timelines may be subject to adjustment depending on recruitment rate, regulatory review, preclinical and clinical results, funding, and other factors that could delay the initiation, enrollment, or completion of clinical trials.

Important factors that could cause actual results to differ materially from those reflected in Aldeyra's forward-looking statements include, among others, the timing of enrollment, commencement and completion of Aldeyra's clinical trials, the timing and success of preclinical studies and clinical trials conducted by Aldeyra and its development partners; delay in or failure to obtain regulatory approval of Aldeyra's product candidates, including as a result of the FDA not accepting Aldeyra's regulatory filings, issuing a complete response letter, or requiring additional clinical trials or data prior to review or approval of such filings.