Key Takeaways

  • Tarsus Pharmaceuticals has entered into a definitive agreement to acquire Alkeus Pharmaceuticals, adding phase 3 candidate gildeuretinol (ALK-001) to Tarsus’ retina portfolio
  • The therapy for Stargardt disease is being evaluated in the ongoing phase 3 NORTHSTAR trial, with topline results anticipated in the second half of 2029
  • The acquisition includes approximately $450 million in upfront consideration, up to $350 million in milestone payments upon potential regulatory approval and first commercial sale, and low single-digit tiered descending royalties as a percentage of gildeuretinol net sales

Tarsus Pharmaceuticals announced that it has entered into a definitive agreement to acquire Alkeus Pharmaceuticals, a privately held biotechnology company focused on retinal diseases that is developing gildeuretinol (ALK-001), an investigational once-daily oral therapy for Stargardt disease. The molecular entity is designed to reduce the accumulation of toxic dimers while preserving the normal visual cycle.

Tarsus expects the pending acquisition to expand the company’s presence in retina, complement the capabilities established through the acquisition of iRenix Medical, and add a differentiated phase 3 program potentially addressing Stargardt disease.

“We believe gildeuretinol has the potential to be a transformational medicine for Stargardt disease and complements the retina capabilities we are already building through IRX-101,” said Bobby Azamian, MD, PhD, chief executive officer and chairman of Tarsus.

According to a company press release, the clinical program to date has evaluated ALK-001 across all stages of Stargardt disease. Together, the TEASE-1 and TEASE-2 studies reportedly informed the design of NORTHSTAR, the ongoing phase 3 trial expected to enroll approximately 230 patients. Per Tarsus, the primary endpoint will measure the rate of retinal atrophic lesion growth over 24 months, and the secondary endpoint will assess a key aspect of visual function, change in low light visual acuity. The trial was agreed to by the US FDA and the European Medicines Agency, and topline data are expected in the second half of 2029, Tarsus stated.

Pending transaction details per a company press release were as follows:

  • Upfront consideration: approximately $450 million, consisting of $270 million in cash and $180 million in Tarsus common stock;
  • Milestones: up to $350 million upon potential regulatory approval and first commercial sale; and
  • Royalties: low single-digit tiered descending royalties as a percentage of gildeuretinol net sales.

The Tarsus common stock to be issued to the Alkeus stockholders at closing of the acquisition will reportedly be priced at $61.38 per share. According to Tarsus, the pending transaction with Alkeus has been approved by the boards of directors of both companies and the stockholders of Alkeus and is expected to close in 2026.