Kalaris Unveils Expanded Phase 1a Data for TH103 in nAMD, Highlighting Durable Responses and a Clean Safety Profile at the 2.5 mg Dose

summarizeSummary

Kalaris Therapeutics reported expanded Phase 1a data for TH103 in nAMD, showing durable responses and a clean safety profile at the 2.5 mg dose. The results support TH103's potential as a longer-acting anti-VEGF therapy and de-risk the ongoing Phase 1b/2 trial.

check_boxKey Events · Product Development and Regulatory · KLRS

• Expanded Phase 1a Data Released

  Kalaris reported additional data from its Phase 1a SAD trial of TH103 in nAMD, expanding the dataset to 17 treatment-naive patients (from 13 in Dec 2025) and adding 3 treatment-experienced patients. All 20 patients completed 6-month follow-up.

• Clean Safety at 2.5 mg Dose

  No cases of intraocular inflammation were observed in 6 patients treated at the 2.5 mg dose using improved manufacturing batch #2, addressing a prior safety concern where 2 patients had mild/moderate IOI with batch #1.

• Durable Responses After Single Injection

  41% of treatment-naive patients (7 of 17) had first retreatment at 4 months or later, 35% at 5 months or later, and 29% (5 patients) required no additional anti-VEGF treatment through the entire 6-month follow-up period.

• Robust Efficacy Confirmed

  Mean 9.2-letter BCVA improvement and mean 118µm reduction in central subfield thickness at one month after a single TH103 injection, consistent with previously reported rapid, robust responses.

auto_awesomeAnalysis · KLRS · Life Sciences

Kalaris released expanded Phase 1a data for its lead asset TH103 in neovascular AMD, adding 4 new treatment-naive patients and 3 treatment-experienced patients to the previously reported 13-patient dataset. The new data reinforce rapid, robust efficacy (mean 9.2-letter BCVA gain, 118µm CST improvement at one month) and show a clean safety profile at the 2.5 mg dose using improved manufacturing — no intraocular inflammation in 6 patients, addressing a key prior concern. Durability signals are compelling: 41% of treatment-naive patients went ≥4 months before first retreatment after a single injection, and 29% needed no anti-VEGF through 6 months. These results strengthen the case for TH103 as a potential best-in-class, longer-acting anti-VEGF therapy and de-risk the ongoing Phase 1b/2 trial, with initial data expected in 1H 2027. The update comes against a backdrop of cash runway into Q4 2027 and a recent insider accumulation signal, but the company still faces significant dilution risk from an active $100M ATM program.