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.

The company says that currently, randomized clinical trials of ADX-2191 in PVRL, a rare and fatal cancer with no approved therapy, are not feasible.

The company notes that methotrexate, the compounded intravitreal injection of which is the standard of care for PVRL, is currently in shortage, per the FDA Drug Shortages database. 

ADX-2191 is also under development for proliferative vitreoretinopathy and retinitis pigmentosa, both rare, sight-threatening retinal diseases. 

Topline results from a Phase 2 clinical trial of ADX-2191 in retinitis pigmentosa are expected this month. Additionally, Aldeyra plans to conduct a Type C meeting with the FDA in 2H 2023 to discuss the completion of clinical development of ADX-2191 for proliferative vitreoretinopathy.

Recently, Aldeyra Therapeutics released topline results from the Phase 3 trial of 0.25% reproxalap ophthalmic solution for allergic conjunctivitis, achieving statistical significance for the primary and secondary endpoints.

Price Action: ALDX shares are down 24.80% at $8.00 on the last check Wednesday.