Werewolf Therapeutics has announced that the U.S. Food and Drug Administration (FDA) has granted Fast Track Designation to its lead candidate WTX-124, a conditionally activated interleukin-2 (IL-2) INDUKINE™ therapy, for the treatment of patients with locally advanced or metastatic cutaneous melanoma who have progressed following standard immunotherapy.
WTX-124 is currently being evaluated in a Phase 1/1b clinical trial as both a monotherapy and in combination with pembrolizumab in patients with multiple advanced solid tumors. The investigational drug is designed to stimulate a potent anti-tumor immune response by delivering IL-2 selectively to the tumor microenvironment, potentially avoiding the systemic toxicities seen with earlier IL-2 therapies.
“At Werewolf, we are focusing on efforts to address the high unmet need of cancer patients, and we believe there is significant opportunity with WTX-124 for the potential treatment of advanced cancers,” said Daniel J. Hicklin, PhD, President and CEO of Werewolf Therapeutics. “This Fast Track Designation marks an important milestone for the WTX-124 program and highlights the urgency for new treatments in patients with relapsed or refractory melanoma.”
The FDA’s Fast Track program is intended to accelerate the development and review of therapies that address serious or life-threatening conditions and fill an unmet medical need. Drugs receiving this designation may benefit from more frequent interactions with the FDA, priority review, and potential eligibility for rolling submissions and accelerated approval.
The designation for WTX-124 was granted based on early clinical data showing clinically meaningful anti-tumor activity and a favorable safety profile in melanoma patients previously treated with immune checkpoint inhibitors.
Werewolf Therapeutics anticipates sharing preliminary clinical data from the ongoing WTX-124 Phase 1/1b trial, including results in patients with cutaneous melanoma, in Q4 2025, along with updates on its regulatory strategy.
WTX-124 represents a new class of engineered cytokine therapies designed to maximize efficacy while minimizing immune-related toxicities—offering a potential breakthrough for patients with few remaining treatment options.