Eli Lilly agreed to acquire Centessa Pharmaceuticals for about $6.3 billion upfront (plus contingent value rights), betting its neuroscience cash flow on orexin receptor 2 (OX2R) agonists. Centessa’s cleminorexton (ORX750) produced Phase 2a results across narcolepsy types 1 and 2 and idiopathic hypersomnia, giving Lilly a clinical-stage entry into a high-unmet-need sleep-disorders market. In a separate landmark deal, Biogen agreed to buy Apellis Pharmaceuticals for about $5.6 billion, adding two approved immunology/eye assets—Empaveli (pegcetacoplan) and Syfovre (pegcetacoplan)—and expanding Biogen’s downstream reach. Syfovre is tied to geographic atrophy secondary to age-related macular degeneration, while Empaveli targets rare complement-mediated kidney diseases. Together, the acquisitions underline how large biopharma is rebalancing portfolios toward commercial products plus late-stage clinical expansion, particularly in immune-mediated disease and neuro areas where growth is tied to pipeline execution and market access. Deal structure also matters: both transactions include contingent payments based on milestones, aligning investor expectations with regulatory progress and sales thresholds.