05:49 PM EDT, 09/03/2025 (MT Newswires) -- Avadel Pharmaceuticals ( AVDL ) secured an exclusive license to develop and commercialize XWPharma's sleep disorder treatment, valiloxybate, including a $20 million upfront payment.

Avadel gains the global rights, excluding mainland China, Hong Kong and Macau, and XWPharma is eligible for development and regulatory milestone payments of up to $30 million, the companies said Wednesday in a statement.

Additionally, Avadel agreed to pay Wuhan, China-based XWPharma up to $155 million in tiered sales milestones for the first achievement of annual net sales up to $750 million, with further milestone payments for sales exceeding $750 million and up to $3.5 billion.

Dublin-based Avadel plans to initiate a pharmacokinetic study of the valiloxybate formulation in Q4, followed by a clinical trial in H2 2026.

Valiloxybate is a once-at-bedtime, salt-free and artificial sweetener-free compound designed to treat narcolepsy and idiopathic hypersomnia.