Kairos Pharma Ltd. (NYSE American: KAPA) announced a strategic collaboration with Bayer to evaluate its lead antibody candidate, ENV-105 (carotuximab), in combination with Bayer’s XOFIGO (radium-223 dichloride) for the treatment of metastatic castration-resistant prostate cancer (mCRPC) involving bone. ENV-105 is a first-in-class CD105/BMP signaling inhibitor designed to overcome cancer drug resistance and is currently in Phase 1 and Phase 2 clinical trials. Interim Phase 2 data showed median progression-free survival exceeding 13 months in prostate cancer patients, while XOFIGO is the only FDA-approved alpha-emitting radiopharmaceutical for symptomatic bone metastases in this population.
The collaboration will assess whether ENV-105 can enhance responses to XOFIGO by targeting CD105, a protein associated with treatment resistance following androgen receptor inhibition and radiation therapy. Preclinical studies have demonstrated ENV-105’s ability to re-sensitize tumors to radiation, and management believes the combination could offer a more durable treatment option for advanced prostate cancer patients.
Kairos Pharma, based in Los Angeles, focuses on overcoming drug resistance and immune suppression in cancer using structural biology. Its lead candidate, ENV-105, targets CD105—a key driver of resistance and relapse in response to standard therapies. The antibody is in a Phase 2 trial for castrate-resistant prostate cancer and a Phase 1 trial for non-small cell lung cancer. As of the press release date, ENV-105 has not been approved by the FDA or any other regulator.
