Janux Therapeutics announced an exclusive worldwide license and collaboration with Bristol Myers Squibb to develop tumor‑activated therapeutics from Janux’s TRACTr and related platforms. The arrangement includes $50 million in near‑term payments and up to ~$800–$800+ million in development, regulatory and commercial milestones. Bristol Myers said the deal validates tumor‑activated T‑cell engagers that aim to limit systemic toxicity by activating in the tumor microenvironment. Janux’s technology uses masking strategies that are cleaved or activated locally to reduce off‑tumor effects. The partnership follows similar industry interest in tumor‑restricted engager formats. Clarification: tumor‑activated or “masked” engagers are designed to remain inert in circulation and become active in protease‑rich tumor sites, improving safety margins for potent T‑cell engaging drugs.