Eli Lilly to acquire Centessa in $6.3 Billion to Expand Sleep Disorder Pipeline

Rare Daily Staff

Eli Lilly agreed to acquire Centessa Pharmaceuticals in a deal valued at about $6.3 billion upfront, as the drugmaker moves deeper into treatments for sleep-wake disorders.

Lilly said the acquisition will strengthen its neuroscience portfolio and expand its capabilities in sleep medicine, an area gaining renewed attention as researchers better understand the biological mechanisms behind sleep disorders.

Centessa, a clinical-stage company based in Boston and London, has focused on developing orexin receptor agonists not only for sleep disorders but also for broader neurological and psychiatric conditions.

The agreement gives Lilly access to Centessa’s experimental medicines targeting the orexin system, a key regulator of the sleep-wake cycle. The companies said the acquisition could help accelerate development of new therapies for conditions marked by excessive daytime sleepiness, including narcolepsy and idiopathic hypersomnia—both rare and often debilitating disorders.

Centessa’s lead drug candidate, cleminorexton, has shown encouraging results in mid-stage clinical trials across narcolepsy type 1, narcolepsy type 2, and idiopathic hypersomnia. The therapy is designed to activate the orexin receptor 2 pathway, which plays a central role in maintaining wakefulness.

Current treatments for these conditions often rely on stimulants or symptom management, leaving a significant unmet need for therapies that address the underlying biology. Orexin-based drugs aim to restore normal wake signaling rather than simply masking symptoms.

Under the terms of the deal, Lilly will pay $38 per share in cash, plus a contingent value right that could add up to $9 per share if certain regulatory milestones are met. That brings the total potential value to about $47 per share. The transaction also includes up to $1.5 billion in additional milestone-based payments.

The companies expect the deal to close in the third quarter of 2026, pending shareholder approval, regulatory clearance, and court approval in the United Kingdom, where Centessa is incorporated.

“Orexin receptor biology represents one of the most compelling mechanistic opportunities in neuroscience as a direct intervention on the master switch of the sleep-wake cycle,” said Carole Ho, executive vice president and president of Lilly Neuroscience. “Centessa has assembled a portfolio with the breadth and depth to improve wakefulness across a broad array of indications.”