A Phase 1 interventional study of ATR12-351 in Netherton Syndrome, sponsored by Azitra Inc.. Completed at 2 sites in United States. Open to participants aged 18 Years and older. Per ClinicalTrials.gov, last updated 2026-07-29.
Sponsored by Azitra Inc. · Phase 1, Interventional, and Treatment
The objectives of this clinical trial are to evaluate the safety and tolerability of topically applied ATR12-351, to understand what the body does to ATR12-351, and to observe treatment benefits of the drug in approximately 12 adult patients with Netherton Syndrome (NS). ATR12-351 will be applied to skin lesions on one side of the body, while the vehicle control will be applied to similar lesion on the other side of the body twice daily for 2 weeks.
Netherton syndrome (NS) is a rare but severe autosomal recessive disease that affects the skin, hair, and immune system. NS presents at birth with red skin covered by fine scales, a specific hair shaft abnormality ("bamboo hair"), atopic lesions, and elevated systemic immunoglobulin E (IgE) levels. Patients often develop allergies and asthma, and the unfortunate prognosis for infants with NS is poor, with 10% mortality in the first 6 months of life and recurrent infections. There are no FDA-approved treatment options for NS. NS is caused by mutations in in the SPINK5 gene encoding the serine protease inhibitor lymphoepithelial Kazal-type related inhibitor (LEKTI). Absence of LEKTI causes unregulated activity of proteases in the kallikrein subfamily, causing excessive desquamation of skin.
ATR12-351 is a topical ointment containing a lyophilized version of a live biotherapeutic product (LBP), Staphylococcus epidermidis (SE) strain designated SE351. This strain has been modified to be auxotrophic and to express recombinant human LEKTI protein (rhLEKTI). ATR12-351 is intended to address the underlying cause of NS by replacing deficient/dysfunctional LEKTI. The treatment consists of applying ATR12-351 to affected areas, where rhLEKTI produced by ATR12-351 will counter the dysregulated skin serine protease activity observed in NS patients.
This first-in-human study is a randomized, double-blind, vehicle-controlled clinical study to assess the safety, tolerability, and pharmacokinetics (PK) of topical ATR12-351 in approximately 12 adult Netherton syndrome patients who will serve as their own control. This study will include a 14-day treatment period to investigate the safety and tolerability of ATR12-351 applied to the skin and will be followed a total of 84 days for safety. The results of this first-in-human clinical study will establish safety and tolerability as well as initial efficacy of ATR12-351 application in Netherton syndrome patients.
22 studies on the registry are indexed under Netherton Syndrome; 5 are open to participants now.
This study's enrollment of 6 is below the median of 16 across 19 interventional studies indexed under Netherton Syndrome.
Browse Netherton Syndrome studies →Azitra Inc. is the lead sponsor of 4 studies on the registry; 1 is open to participants now.
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Anti-inflammatory medicines such as prednisone, prednisolone and dexamethasone — not the anabolic steroids used for muscle.
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Anti-inflammatory medicines such as prednisone, prednisolone and dexamethasone — not the anabolic steroids used for muscle.
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ATR12-351 on left side of body, vehicle on right side of body in one group; vehicle on left side of body, ATR12-351 on right side of body.
Drug: ATR12-351
Topical ointment containing ATR12-351, a LEKTI-secreting strain of S. epidermidis
Also known as: ATR-12
Adverse events
Incidence, severity, seriousness and relatedness of all treatment-emergent adverse events
Time frame: 84 days
Investigator's Global Assessment (IGA)
Visual assessment of the overall severity of skin disease severity at each application site, using a 5-point scale (0, clear; 1, almost clear/minimal; 2, mild; 3, moderate; 4, severe). Higher scores indicate greater severity.
Time frame: 42 days
Patient's Global Assessment (PGA)
Visual assessment of the overall severity of skin disease severity at each application site, using a 5-point scale (0, clear; 1, almost clear/minimal; 2, mild; 3, moderate; 4, severe). Higher scores indicate greater severity.
Time frame: 42 days
NS-modified SCORAD
The investigator's objective assessment of the severity (peeling, scaling, lichenification, erythema, papules) and extent (surface of affected skin areas) of skin disease at each application site is combined with patient's subjective scores (pain and pruritus). Higher scores indicate greater severity with a maximum of 100 points possible.
Time frame: 42 days
Pharmacokinetics: plasma concentration
Concentration (ng/mL) of rhLEKTI in the plasma following topical application.
Time frame: 42 days
Pharmacokinetics: skin concentration (Cmax skin)
Concentration of rhLEKTI in the skin (pmol/cm2), measured by tape stripping, following topical application.
Time frame: 42 days
Plan to share: No
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Ran from Jun 2024 to primary completion in Jul 2026, 24 months.
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