Kalaris reports expanded Phase 1a data for TH103 in wet AMD

Kalaris Therapeutics announced on July 17, 2026, additional results from the expanded cohorts of its Phase 1a single ascending dose trial studying TH103 in patients with neovascular age-related macular degeneration. The expanded dataset now includes 17 treatment-naive patients along with 3 treatment-experienced patients added to the safety cohort, and all 20 patients completed six months of follow-up.¹

TH103's plasma pharmacokinetic profile pointed to longer intraocular retention, showing a Cmax 27 to 53 times lower than current leading anti-VEGF therapies when compared on a molar basis.¹ On retreatment timing, after a single injection, 41% of the 17 treatment-naive patients needed their first retreatment at four months or later, 35% waited until at least five months, and 29% required no further anti-VEGF treatment across the full six-month observation period.¹ Among the three treatment-experienced patients, the interval before retreatment lengthened by an average of two months relative to their prior anti-VEGF treatment schedule.¹

On safety, no intraocular inflammation occurred in the six patients dosed at 2.5 mg using product made with adjusted manufacturing to cut impurities, while one patient at the 5 mg dose had previously reported transient inflammation that resolved without lasting effects.¹

Separately, the trial data showed a mean 9.2-letter improvement in best corrected visual acuity after a single TH103 injection, along with a mean 118 micron reduction in central subfield thickness and a 93% mean reduction in central subfield intraretinal fluid at one month.¹

Kalaris is now enrolling and dosing patients in a Phase 1b/2 trial testing a four-dose loading regimen, with initial data still expected in the first half of 2027 to help guide dose selection for potential Phase 3 studies.¹