Azitra's ATR-01 Shows Promise in Preclinical Studies for Ichthyosis Vulgaris

Azitra, Inc., a clinical-stage biopharmaceutical company specializing in precision dermatology, has announced positive preclinical data for its ATR-01 program, aimed at treating ichthyosis vulgaris.¹ The announcement comes ahead of a detailed presentation by Azitrac co-founder and COO, Travis Whitfill, PhD, MPH, at the upcoming BIO-Europe conference in early November, to be held virtually and in Vienna, Austria.

Ichthyosis vulgaris is a common autosomal semidominant genetic skin disorder that affects approximately 1.3 million people in the US. It is primarily characterized by abnormal or deficient filaggrin, a key structural protein involved in maintaining the skin barrier. Currently, no disease-modifying therapies exist for ichthyosis vulgaris, and treatment is limited to symptom management through emollients and keratolytics.

Azitra's ATR-01 program uses an engineered strain of Staphylococcus epidermidis (ATR01-616) to deliver a functional human filaggrin protein directly to the skin. This live biotherapeutic approach is a novel, topically applied treatment that directly targets the underlying pathophysiology of Ichthyosis vulgaris. In preclinical studies, ATR01-616 demonstrated a strong pharmacologic profile across multiple models:

• In in vitro studies, ATR01-616 secreted biologically active filaggrin, confirmed through keratin-binding assays.
• In ex vivo human skin models, the strain was shown to deliver filaggrin through the stratum corneum and into the lower layers of the epidermis, as visualized by fluorescence immunohistochemistry (p < 0.05).
• In an ex vivo damaged pig skin model, ATR01-616 treatment resulted in a significant reduction in transepidermal water loss (TEWL) compared to vehicle controls (p < 0.002), indicating improved skin barrier function.

These findings support the therapeutic potential of ATR01-616 to restore skin barrier integrity in patients with ichthyosis vulgaris and serve as a foundation for further development. According to Azitra CEO Francisco Salva, these results are a crucial step toward the program’s progression into first-in-human clinical trials, expected to begin in 2026 following an IND submission.

"We're thrilled to announce positive preclinical data for our ATR-01 program during BIO-EUROPE as we advance towards a first-in-human clinical trial in ichthyosis vulgaris," Salva said. "Ichthyosis vulgaris is an autosomal semidominant genetic disorder that impacts approximately 1.3 million in the U.S. who have no treatment options beyond symptom management. We are optimistic that this innovative, topically delivered treatment option has the potential to directly address the disease pathophysiology. We look forward to further updates on this program in 2026, including details around a path to first-in-human studies."¹

In addition to ATR-01, Azitra is advancing 2 other programs thatutilize its platform of engineered live biotherapeutics:

• ATR-12, currently in a Phase 1b trial, is being developed for Netherton syndrome, a rare, life-threatening genetic skin disorder with no approved treatments. ATR-12 uses a different engineered S. epidermidis strain and represents the company’s most advanced candidate.²
• ATR-04 targets EGFR inhibitor-associated rash, a common dermatologic adversr event in oncology patients. The program has received FDA Fast Track designation, and Azitra holds an open IND for clinical development in this indication.

All 3 programs are derived from Azitra’s proprietary technology platform, which combines a library of over 1,500 bacterial strains with artificial intelligence and machine learning tools to identify and optimize therapeutic candidates. This platform enables the company to engineer precise microbial therapies tailored to specific dermatological conditions.

References

1. Azitra, Inc. Announces Positive Preclinical Data for ATR-01 Program, Designed to Treat Ichthyosis Vulgaris. News release. Azitra. Published October 20, 2025. Accessed October 20, 2025. https://ir.azitrainc.com/news-releases/news-release-details/azitra-inc-announces-positive-preclinical-data-atr-01-program

2. Evaluation of Topical ATR12-351 in Adults With Netherton Syndrome, NCT06137157, ClinicalTrials.gov. https://clinicaltrials.gov/study/NCT06137157