Azitra clears safety review, moves ATR-04 trial to Cohort 2

Azitra, Inc. said on October 1, 2026 that it has finished enrolling Cohort 1 of its Phase 1/2 trial testing ATR04-484 as a potential treatment for skin rash linked to EGFR inhibitor cancer therapy. A safety review committee examined available data from Cohort 1 patients and recommended that the study move forward to Cohort 2, allowing the company to start enrolling and dosing patients in that next group.¹ The committee's review was based on data from six patients.¹

The trial, registered as NCT06830863, is a multicenter, randomized, double-blind, vehicle-controlled Phase 1/2 study looking at how ATR-04 performs topically in adults with EGFRi-related dermal toxicity.¹ Researchers are comparing ATR04-484 against a vehicle control in a 3:1 randomization across two cohorts, tracking safety, bioavailability, pharmacodynamics and early efficacy signals.¹ In Cohort 1, seven patients received a single 4g dose applied to the face, chest and back, followed by a week of observation and then daily dosing for 28 days.¹ Cohort 2 is set to add roughly 24 patients, each receiving a 4g dose daily over a 28-day period.¹ Six sites are participating, among them MD Anderson Cancer Center and Yale University.¹

ATR04-484 is built from an isolated, naturally derived strain of Staphylococcus epidermidis and was chosen for its preclinical ability to lower IL-36γ and Staphylococcus aureus levels, both elevated in patients with this type of rash.¹ The strain was also engineered to improve its safety profile by removing an antibiotic resistance gene and building in auxotrophy to limit its growth.¹ The FDA has granted the candidate Fast Track designation for EGFRi-associated rash, a condition the company estimates affects about 150,000 patients annually in the United States.¹