Gilead pays $1.275bn upfront for PepStar's oral IL-23R drug to build all-oral IBD

Gilead Sciences has agreed to buy PepStar Therapeutics' oral IL-23 receptor programme, led by HCXT-2001, for $1.275 billion in cash upfront, payable at closing and subject to customary adjustments. The deal was announced on 23 October and Gilead expects it to close in the fourth quarter of 2026.

What Gilead is getting

HCXT-2001 is an oral macrocyclic peptide designed to block the IL-23 receptor, a target that is already validated in immune-mediated disease. PepStar, a privately held clinical-stage company, has engineered the molecule for a longer half-life, and it is currently in Phase 1. According to Fierce Biotech, registered trials so far are in healthy volunteers in China and New Zealand, including food-effect studies. Gilead's stated focus is inflammatory bowel disease (IBD), and it also sees possible uses in psoriasis.

"HCXT-2001 adds a potentially differentiated oral approach to our growing inflammation pipeline." Dietmar Berger, MD, PhD, Chief Medical Officer, Gilead

Gilead says the deal will reduce its GAAP and non-GAAP earnings per share by roughly $0.79 to $0.83 in Q4 2026.

Why the timing matters

The purchase follows Gilead's own good news in ulcerative colitis. At UEG Week in Barcelona, its once-daily oral α4β7 integrin blocker emvistegrast met the primary endpoint of the 238-patient Phase 2 SWIFT study. BioSpace reported a 66% clinical response rate on the 200 mg dose against 37% for placebo, and clinical remission of 31% against 8%. A Phase 3 study in ulcerative colitis is due to start next year.

Berger said Gilead sees potential for HCXT-2001 on its own or alongside emvistegrast. Analysts at BMO Capital Markets, quoted by Fierce, described the deal as "a logical complement to emvistegrast that sets up a potential all-oral combination."

The competitive field

Gilead is not first to the oral IL-23 idea. Johnson & Johnson's once-daily Icotyde is already approved in plaque psoriasis, and Fierce notes that AbbVie's Skyrizi, whose label spans psoriasis, psoriatic arthritis and both forms of IBD, brought in nearly $10 billion in the first half of the year. BMO's analysts see less frequent dosing and the emvistegrast pairing as the likely points of difference.

The bigger picture

Inflammation is the main way Gilead is trying to broaden its business beyond HIV. The deal also lands in the same week that both China and the US moved on rules for biotech ownership and investment, as BioSpace notes, with both proposals leaving licensing deals out of scope. Buying a single programme, rather than a company, keeps deals like this one workable.