Italian family-owned Angelini Pharma SpA is making its first move into the U.S. market, acquiring rare diseases specialist Catalyst Pharma Inc. in an all-cash deal worth $4.1 billion. The acquisition gives Angelini ownership of three marketed drugs for treating epilepsy and neuromuscular diseases that had combined sales of $589 million in 2025, a 19.8% increase over 2024.

Entering what Mirum Pharmaceuticals Inc. CEO Chris Peetz called “a new phase of growth and value creation,” the company plans to submit an NDA to the U.S. FDA in the second half of this year, based on phase IIb data from the Vistas trial with oral ileal bile acid transporter (IBAT) inhibitor volixibat in primary sclerosing cholangitis (PSC).

Eli Lilly and Co. is acquiring Ajax Therapeutics Inc. for up to $2.3 billion in cash, gaining access to next-generation JAK inhibitors for patients with myeloproliferative neoplasms.

Becoming the first and only fully FDA-approved treatment for focal segmental glomerulosclerosis (FSGS), Travere Therapeutics Inc.’s Filspari (sparsentan) has gained access to a second lucrative market with a regulatory package that validates proteinuria as a surrogate endpoint.

With three rare pediatric disease priority review vouchers (RPD PRVs) awarded just since the end of March, the nearly year-and-a-half lapse in the program’s reauthorization seems to have had little short-term impact. The three new vouchers bring the total RPD PRVs granted so far this year to seven – one more than the agency issued all last year and down two from the nine given in 2024.

A proposal to buy out Soleno Therapeutics Inc. didn’t wait for European approval of Vykat XR (diazoxide choline) to treat hyperphagia in Prader-Willi syndrome, as Neurocrine Biosciences Inc. is putting on the table $53 per share in cash, which equates to an equity value of $2.9 billion.

Chiesi Group’s idebenone faced a regulatory setback last month after the U.S. FDA issued a complete response letter (CRL) to the company’s NDA for Leber hereditary optic neuropathy (LHON), a rare inherited disorder that causes sudden vision loss.But a chance missed for Chiesi may be an opportunity for gene therapies, including Gensight Biologics SA’s lenadogene nolparvovec (Lumevoq; GS-010).

In a win for the rare disease space, the U.S. FDA granted accelerated approval for Rocket Pharmaceuticals Inc.’s Kresladi (marnetegragene autotemcel) as the first gene therapy option for treating severe leukocyte adhesion deficiency-I (LAD-I), an ultrarare genetic immune disorder characterized by an immunodeficiency predisposing those affected to recurrent and fatal infections.

With the U.S. FDA’s approval of GSK plc’s ileal bile acid transporter (IBAT) inhibitor, Lynavoy (linerixibat), patients with primary biliary cholangitis no longer need off-label treatments for a debilitating internal itch symptom called cholestatic pruritus.