Kalaris Therapeutics, Inc.

Kalaris Therapeutics, Inc. is a clinical stage biopharmaceutical company focused on developing and commercializing treatments for prevalent retinal diseases with significant unmet medical needs. The company is developing TH103, a novel, clinical stage anti-vascular endothelial growth factor (VEGF) drug. TH103 is engineered for extended intraocular retention and enhanced VEGF inhibition in patients with exudative and/or neovascular retinal diseases. It is a fully humanized recombinant fusion protein that functions as a "decoy receptor" (a VEGF trap), utilizing molecular properties of the human body's native, highest affinity VEGF receptor 1. Preclinical studies comparing TH103 to aflibercept, a current market-leading anti-VEGF agent, demonstrated more anti-VEGF activity and longer duration of activity for TH103. In December 2025, initial data from the Phase 1a single ascending dose (SAD) trial of TH103 in treatment-naïve neovascular Age-related Macular Degeneration (nAMD) patients showed TH103 was generally well tolerated and improved functional and anatomical outcomes at 1-month post-dosing. Preliminary single dose pharmacokinetic data from this trial suggest TH103 may offer extended treatment durability after a standard four-dose loading regimen. Kalaris Therapeutics, Inc. is investigating TH103 for nAMD, a leading cause of blindness in the United States and Europe, affecting an estimated 1.6 million adults in the United States. The global branded market for prevalent exudative and/or neovascular retinal diseases was an estimated $15 billion in 2024.