Alkermes plc has announced it will acquire Avadel Pharmaceuticals in a deal valued at up to USD 2.1 billion, marking the company’s strategic entry into the sleep medicine market.

Under merger terms, Avadel shareholders will receive USD 18.50 per share in cash, and will also be granted contingent value rights (CVRs) worth up to USD 1.50 per share if Avadel’s lead product, Lumryz, obtains FDA approval for idiopathic hypersomnia by the end of 2028. The combined offer values each Avadel share at up to USD 20, representing a premium over its previous trading price. The deal is expected to close in the first quarter of 2026, subject to customary approvals and a court-sanctioned scheme of arrangement.

Lumryz, a once-at-bedtime oxybate formulation, is already approved for treating cataplexy and excessive daytime sleepiness in patients from seven years of age with narcolepsy. The acquisition bolsters Alkermes’ portfolio and provides a commercial platform to support its development pipeline in hypersomnolence disorders.

Alkermes plans to fund the transaction through a combination of cash reserves and new debt. Leadership from both organisations anticipate synergies and complementary capabilities that may enhance Alkermes’ standing in the commercial sleep medicine arena.