Angelini Pharma has agreed to buy Catalyst Pharmaceuticals for $4.1bn, marking the Italian company’s first acquisition since 2021 and its first major move into the US market.
Catalyst, a Florida-based company, develops treatments for rare neuromuscular and neurological conditions. Founded in 2002, its portfolio includes amifampridine, the only FDA-approved treatment for Lambert-Eaton myasthenic syndrome in patients aged six and older, vamorolone for Duchenne muscular dystrophy and the antiepileptic perampanel.
Major deal
Under the terms of the agreement, Angelini will pay $31.50 per share for all outstanding Catalyst stock, a 28% premium to the 30-day average trading price. Both boards have unanimously approved the deal, which is expected to close in the third quarter of 2026, pending shareholder and regulatory approval.
The price tag dwarfs Angelini’s last major purchase in 2021, when it acquired Swiss-based Arvelle Therapeutics for up to $960m, securing European rights to the epilepsy drug cenobamate. Today’s deal is more than four times that size and roughly equivalent to three years of Angelini’s total turnover – the company reported revenues of €1.2bn in 2024.
Why spend $4.1bn?
Sergio Marullo di Condojanni, CEO, Angelini, said the Catalyst takeover would cement the company’s ambitions in CNS disorders. “We take another significant step with the acquisition of Catalyst, which we believe will establish Angelini as a relevant global player in neurological rare diseases,” he said. “Entering the US market will allow us to acquire the scale and capabilities needed to continue this journey.”
The Italian group has already been building out its epilepsy business, striking deals with GRIN Therapeutics and Sovargen for experimental epilepsy drugs last year, but this deal is by far its biggest move yet.
Rich Daly, CEO, Catalyst, said he hoped the purchase would expand patient access to its treatments. “By combining our unique capabilities in rare diseases with Angelini’s proven global reach, we will create a stronger rare disease platform to expand access to life-changing therapies worldwide,” he said.
A clean break
Separate to the transaction, Catalyst has announced it has settled a long-running patent dispute with generic drugmaker Hetero USA. The case surrounds amifampridine, which Hetero wants to produce a generic version of in the US. However, they applied to the FDA before the patents had expired, which led Catalyst to launch legal proceedings in 2023.
Under the settlement, Hetero has agreed not to market a generic version in the US before 1 October 2035, which protects earnings for at least eight years for Angelini.
