Azitra advances ATR-04 trial to Cohort 2 after safety review

Azitra, Inc. said on October 1, 2026, that the safety review committee for its Phase 1/2 clinical trial of ATR04-484 recommended that the trial proceed to Cohort 2, after the committee reviewed available safety data from patients enrolled in Cohort 1. The company announced the completion of Cohort 1 in a press release filed as Exhibit 99.1 to a Form 8-K dated October 1, 2026.

The trial design

The multicenter, randomized, double-blind, vehicle-controlled Phase 1/2 study, registered as NCT06830863, is designed to evaluate the safety and tolerability of topical ATR-04 for EGFR inhibitor-associated dermal toxicity in adult patients. The company says the safety, bioavailability, pharmacodynamics and preliminary efficacy of ATR04-484 are being compared with its vehicle, using 3:1 randomization, in two patient cohorts. The study is being conducted at six clinical sites, including MD Anderson Cancer Center and Yale University.

Seven patients in Cohort 1 received a single 4g application of ATR04-484 to the face, chest and back. That was followed by a 7-day observation period and then once-daily application for 28 days. The safety review was based on six patients.

Cohort 2

Cohort 2 is expected to enroll approximately 24 patients, who will each receive a 4g application once daily for 28 days. Chief Executive Officer Francisco Salva said that proceeding to Cohort 2 "represents an important milestone for our ATR-04 program," and that the company believes ATR-04 has the potential to become the first live biotherapeutic specifically developed for cancer treatment-associated rash, a debilitating side effect that can disrupt life-saving treatment.

The release says EGFR inhibitors frequently cause a painful papulopustular skin rash that affects approximately 50-80% of patients, and the rash can lead to dose reductions, treatment interruptions or discontinuation.

The program

ATR04-484 is a live biotherapeutic product candidate that includes an isolated, naturally derived Staphylococcus epidermidis strain. The strain was selected for its preclinical profile of reducing IL-36γ and Staphylococcus aureus levels, both of which are elevated in patients with EGFR inhibitor-associated skin rash. It was then engineered to delete an antibiotic resistance gene and to use auxotrophy to control its growth.

The FDA has granted Fast Track designation to ATR04-484 for the treatment of EGFR inhibitor-associated rash, which the company says affects approximately 150,000 patients annually in the United States. The company describes itself as a clinical-stage biopharmaceutical company focused on precision dermatology, with cosmetic and biotechnology applications also in development.

Financial position

The company's annual report on Form 10-K, filed February 27, 2026, reports research and development expense of $4.8 million for 2025 and a net loss of $11.0 million. The annual report also shows no revenue for 2025, compared with $7,500 in 2024.

The company reported cash and cash equivalents of $6.7 million at June 30, 2026, in its quarterly report filed August 12, 2026. Cash and cash equivalents were $2.1 million at the end of 2025, according to the same report.

What comes next

The release reports no efficacy data and no detail on adverse events. Seven patients were dosed in Cohort 1, the safety review rested on six, and the committee recommended only that the trial may proceed. The chief executive's phrase "positive safety data" is the company's description of that small sample. The study is early, and Cohort 2 of about 24 patients is still to be enrolled. The company reported no revenue for 2025 and a net loss of $11.0 million. Cash and cash equivalents were $6.7 million at June 30, 2026, against cash used in operations of $11.2 million in 2025. The release gives no date for the start of enrollment or for any results from Cohort 2.

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