Advancing PTC-2105 Toward the Clinic

Eos is in the preclinical stage of development of PTC-2105 and is conducting IND-enabling studies to support the initiation of first-in-human clinical trials, which will be led by Roger A. Fielding, Ph.D., of the Jean Mayer USDA Human Nutrition Research Center on Aging at Tufts University, and Nathan K. LeBrasseur, Ph.D., Director of the Robert and Arlene Kogod Center on Aging at Mayo Clinic, as Co-Principal Investigators — two of the field's leading authorities in sarcopenia and the biology of aging, respectively.

Advancing on an Emerging Therapeutic Field

Eos’s next generation mitochondria-targeted MitoXcel™ geropeptides, licensed from SENOTHERAPEUTIX, Inc., seek to build on the science behind Stealth Bio’s FORZINITY™ (elamipretide), a tetrapeptide (4 amino acids) recently granted accelerated approval by the FDA for the treatment of Barth syndrome, a rare, serious, and life-threatening disease characterized by muscle weakness, chronic fatigue, and low muscle mass. FORZINITY was granted accelerated approval based on improvement in knee extensor muscle strength. While Stealth Bio, recently renamed Mighty Therapeutics, is still required to conduct post-approval trials to confirm FORZINITY’s long term clinical effectiveness, FORZINITY remains the first FDA-approved therapy that directly targets mitochondria. Underscoring growing scientific interest in mitochondrial biology as a target in aging, a joint Mighty Therapeutics and University of Washington team was named a finalist and, in August 2026, a Milestone 2 Awardee in the $101 million XPRIZE Healthspan competition, based on pilot data evaluating elamipretide in older adults. While no relationship exists between the two companies, Eos’s programs are designed to further advance the inner mitochondrial membrane as a target through its next-generation MitoXcel™ geropeptides.