Angelini Pharma Acquires Catalyst Pharmaceuticals in $4.1 Billion Deal for U.S. Rare Disease Market Entry

Angelini Pharma's $4.1 billion acquisition of Catalyst Pharmaceuticals hands the Rome-based company an established U.S. commercial infrastructure and three FDA-approved rare disease assets, a combination that will require careful integration planning across quality systems, supply chains, and post-market commitments already in place at Catalyst.

The all-cash deal, priced at $31.50 per share, represents a 28% premium to Catalyst's 30-day volume-weighted average price as of April 22, 2026. Both boards approved the transaction unanimously; closing is targeted for Q3 2026, subject to regulatory clearance. Financing is structured with BNP Paribas acting as Sole Global Coordinator and Underwriter, with participation from Blackstone funds and select international partners.

For manufacturing and QA leads, the inherited portfolio carries immediate compliance obligations. Catalyst's three commercial products, FIRDAPSE® (amifampridine) for Lambert-Eaton myasthenic syndrome, AGAMREE® (vamorolone) for Duchenne Muscular Dystrophy, and FYCOMPA® (perampanel) for epileptic seizures, each carry active FDA post-approval commitments and established GMP supply chains. AGAMREE received FDA approval in 2023; FYCOMPA's U.S. rights were acquired from Eisai the same year, meaning both products are still within their early post-approval surveillance windows.

Angelini Pharma has stated its intent to integrate Catalyst's commercial infrastructure with its own Brain Health portfolio, which includes Ontozry®, and to build what it describes as a next-generation rare disease therapeutic platform. The company's Italian manufacturing sites are designated to remain active as production and scientific centers within the combined entity's global operations, a signal that supply network rationalisation will be a near-term operational priority for plant heads on both sides of the transaction.

For regulatory affairs leads, the cross-border ownership change will trigger MAH transfer procedures in applicable jurisdictions and may prompt FDA review of manufacturing site registrations under 21 CFR Part 314, depending on how Angelini structures the post-close legal entity. ICH Q10-aligned pharmaceutical quality system integration across two distinct corporate cultures and regulatory geographies will set the pace for how quickly the combined portfolio can be managed under a unified compliance framework.

The measurable near-term checkpoint is the Q3 2026 close, after which the pace of quality system integration and supply chain consolidation will determine whether Angelini can sustain uninterrupted product availability for LEMS and DMD patient populations with limited treatment alternatives.

Source: GlobeNewswire via Angelini Pharma / Catalyst Pharmaceuticals joint press release, May 7, 2026.