Tarsus Pharmaceuticals to Acquire Alkeus for Up to $800M, Gaining Late-Stage Stargardt Disease Drug

Tarsus Pharmaceuticals has agreed to acquire Alkeus Pharmaceuticals for up to $800 million, including $450 million upfront ($270 million cash and $180 million stock) and $350 million in milestones. The deal adds gildeuretinol (ALK-001), a Phase 3 oral drug for Stargardt disease, an inherited retinal disorder affecting 36,000 Americans with no approved therapies. The acquisition is funded by Tarsus' strong commercial foundation, highlighted by Q2 2026 XDEMVY sales of $173.9 million, a 69% year-over-year increase.

Alkeus acquisition deal structure

• ▪The acquisition agreement between Tarsus Pharmaceuticals and Alkeus Pharmaceuticals includes up to $350 million in potential regulatory and first-commercial-sale milestones, plus low single-digit tiered descending royalties on net sales of gildeuretinol.
• ▪The pending acquisition of Alkeus Pharmaceuticals by Tarsus Pharmaceuticals has been approved by both companies' boards and Alkeus stockholders, and is expected to close in 2026 subject to Hart-Scott-Rodino antitrust clearance.
• ▪Tarsus Pharmaceuticals entered a definitive agreement on August 6, 2026 to acquire Alkeus Pharmaceuticals for approximately $450 million upfront, consisting of $270 million in cash and $180 million in stock.

XDEMVY quarterly sales growth

• ▪Tarsus Pharmaceuticals generated $173.9 million in XDEMVY net product sales for the second quarter of 2026, representing a year-over-year increase of more than 69% compared to $102.7 million in the second quarter of 2025.
• ▪Tarsus Pharmaceuticals increased its full-year 2026 XDEMVY net product sales guidance to a range of $685 million to $705 million.

Gildeuretinol Phase 3 trial

• ▪In clinical studies, gildeuretinol demonstrated a 29.5% slower annualized growth rate of atrophic lesions compared to the untreated arm, and treated patients were 87% less likely to experience significant loss in low-light visual acuity.
• ▪The ongoing Phase 3 NORTHSTAR trial of gildeuretinol is designed to enroll approximately 230 patients, with topline data expected in the second half of 2029.
• ▪Gildeuretinol has been evaluated in more than 400 individuals, with some patients treated for over seven years, and has received Breakthrough Therapy, Orphan Drug, and Rare Pediatric Disease designations.

Stargardt disease market opportunity

• ▪Stargardt disease is an inherited retinal disease that progressively damages central vision, affecting more than 36,000 clinically diagnosed patients in the United States, with no currently FDA-approved therapies.
• ▪Belite Bio completed a rolling submission of a New Drug Application to United States regulators in June 2026 for a rival Stargardt disease treatment that could reach the market before gildeuretinol's Phase 3 data readout.

Alkeus founding by Saad

• ▪Leonide Saad convinced Vertex Pharmaceuticals founder Josh Boger to join Alkeus Pharmaceuticals as executive chairman in 2012 after Alkeus won the MassChallenge startup competition.
• ▪Alkeus Pharmaceuticals raised a $150 million Series B round from outside investors, including Bain Capital Life Sciences and TCGX, to advance gildeuretinol through clinical development.
• ▪Leonide Saad founded Alkeus Pharmaceuticals around a drug licensed from Columbia University in 2010, funding the startup with his own money until raising a $2 million Series A round in 2011.