Pfizer ended the remaining clinical development tied to its $2.3 billion Trillium Therapeutics acquisition, scrapping the second and final clinical-stage candidate linked to the CD47 blocker and associated T-cell engager program. The decision follows earlier discontinuation signals in the portfolio and funnels R&D toward other oncology and obesity assets. The move underscores how large platform bets can unwind quickly when confirmatory progress fails to materialize in late-stage settings. Pfizer’s Trillium exposure is now effectively closed, reducing future pipeline tail-risk associated with that mechanism strategy.