A Phase II, Placebo Controlled, Clinical Trial of Topical TolaSure Targeting Aggregated Mutant Keratin in Epidermolysis Bullosa Simplex

This is a closed-label, Phase II clinical study to assess the efficacy, safety and tolerability of the investigational product (IP), topical TolaSure Gel, 5% w/w, in adults and pediatric patients diagnosed with localized, intermediate, or severe epidermolysis bullosa simplex (EBS). TolaSure Gel, 5% w/w and Placebo tubes will be placed into kits where all labels (tubes and kit labels) will be blinded for drug content. Kits will be bundled (based on expected amount of study gel usage) and distributed randomly to patients [Goal of patient population, 1:1 M:F and approximately 70% pediatric patients].

Each patient (40 to complete) will be enrolled in the study and once a blistering flare is confirmed by the clinical study team, and the patient will be randomized to receive either TolaSure Gel, 5% w/w or Placebo (50:50 chance).

For Part I of the study, participants apply the randomized study treatment once daily for 2 months to a defined Target Lesional Area (TLA). The TLA and clinical presentation required for enrollment for each EBS subtype is described below.

For localized EBS subjects, the TLA will consist of daily treating the feet (tops and bottoms) which is approximately 7% body surface area (BSA). At the Baseline Visit, localized EBS subjects must have at least moderate plantar disease activity, defined as ≥15% involvement of the plantar surface of at least one foot, as assessed by clinical examination or standardized imaging, with evidence of active disease (e.g., blisters, erosions, or crusting). Localized EBS subjects will also have the option to treat their hands (tops and bottoms), which is approximately an additional 6% BSA. Palmoplantar evaluations for localized EBS subjects are separate from the intermediate to severe EBS subjects' TLA-treated regions per protocol.

For intermediate to severe EBS subject, the TLA can be a contiguous or non-contiguous region totaling up to approximately 15-20% BSA, excluding palmoplantar surfaces, groin, and apocrine areas. At the subject Baseline Visit, intermediate to severe EBS subject's TLA must consist of a 2-3% BSA active flaring sub-region consisting mainly of intact or freshly ruptured blisters. Subjects have the option to treat their feet, but plantar evaluation for intermediate to severe EBS subjects is separate from the TLA per protocol.

Study drug (TolaSure Gel, 5% w/w or Placebo Gel) is applied to the entire TLA, not just the symptomatic regions (e.g., blistering, keratoderma, erosions, crusting). If symptoms resolve, treatment continues daily on all assigned TLAs.

For Part 2 of the study, a single arm crossover will then allow those subjects that received Placebo to go on TolaSure Gel, 5% w/w for a subsequent 2 months. The subjects already in the TolaSure Gel, 5% w/w cohort will continue with daily IP application for an additional 2 months as well.

At End of Study (EOS), subjects will cease IP application and EOS procedures will be completed. A subject follow-up visit will occur after 6 months.

The primary endpoint will assess changes in disease severity within the TLAs (excluding palmoplantar surfaces) and recurrence of blistering using clinical imaging of blister surface area over time. The secondary efficacy endpoints will evaluate blistering on the feet, subject self-assessments including pain, itch, modified Foot Function Index (mFFI), and Quality of Life (QoL) assessment. An exploratory endpoint will examine blistering and keratoderma of localized EBS subjects that treat their hands.

Safety endpoints will include the incidence of treatment-emergent adverse events (TEAEs). In order to provide adequate assurance of subject safety, safety monitoring will include physical exams, vital sign measurements, clinical laboratory testing (blood and urinalysis), and urine pregnancy testing (as appropriate). These safety assessments in addition to AE reviews will be sufficient to identify potential TEAEs.

The information obtained from these assessments will be utilized to examine the efficacy of TolaSure treatment in ameliorating EBS symptoms as well as the accuracy of the proposed mechanism of action (MOA) of TolaSure for this disease indication.

Inclusion criteria

• Patient is a male or female at least 2 years of age.
• Patient has a documented diagnosis and confirmed clinical history of localized (previously known as Weber-Cockayne), intermediate (previously Kӧbner), or severe (previously EBS-Dowling Meara) autosomal dominant EBS and/or a genetic mutation in either the KRT14 or KRT5 gene consistent with localized, intermediate, or severe EBS. The Investigator will determine patient eligibility based on historical phenotypic presentation of EBS symptoms along with genetic/diagnosis documentation to determine EBS severity. (If localized, intermediate, or severe EBS is suspected but not diagnosed or genetically confirmed, confirmatory testing will be performed).
• For localized EBS participants:

• Patient must have at least moderate plantar disease activity, defined as ≥15% involvement of the plantar surface of at least one foot, as assessed by clinical examination or standardized imaging, with evidence of active disease (e.g., blisters, erosions, or crusting).
• For treatment, the Target Lesional Area (TLA) will consist of daily treating the feet (tops and bottoms) which is approximately 7% body surface area (BSA). Localized EBS subjects will also have the option to treat their hands (tops and bottoms), which is approximately an additional 6% BSA. Palmoplantar evaluation is separate from the intermediate to severe TLA-treated regions per protocol.
• For intermediate to severe EBS participants: Patient is actively flaring in one of the preferred target lesional areas (TLAs): 1) lower extremities (ideally below the knee and above the ankle or between the knee and top of the thigh) or 2) torso (excluding the groin and apocrine areas). The following skin conditions are required for treatment purposes:

• A TLA is defined as a contiguous or non-contiguous region totaling up to ~15-20% body surface area (BSA).
• A flare is defined as a minimum area of ~2-3% Body Surface Area (BSA) containing intact blisters (of varying size and number), and freshly ruptured blisters across 50% of the TLA (as assessed by the principal investigator (PI)). Skin erosions, keratoderma, fissures and/or erythema may also be present.
• Patients will be permitted to treat their feet to assess plantar blister surface area but blistering on the feet is not a requirement for study inclusion and is evaluated separately per protocol.
• For all patients (with localized, intermediate, and severe EBS), the TLA may not be infected (as assessed by PI) or have been treated with a topical antibiotic within 14 days.
• If the patient is a woman of childbearing potential (WOCBP),

• Has a negative urine pregnancy test.
• Agrees to use an approved effective form of birth control with failure rates <1% per year (e.g., implant, injectable, combined oral contraceptive, intrauterine contraceptive device, sexual abstinence, vasectomized partner) during participation in the study (and at least 3 months thereafter).
• Is not nursing.
• Patient's laboratory values (blood and urine) are within the range of normal or abnormal values are within normal levels for the disease and in the opinion of the PI the values are not clinically relevant for study participation.
• Patient is in good, general health and free of any known disease state or physical condition which, in the investigator's opinion, might impair evaluation of the EBS lesions or which exposes the subject to an unacceptable risk by study participation.
• Over the duration of the study, the patient agrees to not use any other topical therapies and/or impregnated dressings within the TLAs (e.g., medicated cleansers, CBD oil, MediHoney, Silvadine cream 1%, topicals containing antimicrobials, keratin, and/or collagen, lipido-colloid or polymeric membrane dressings, and/or hydrogels).
• Patient and/or legally appointed and authorized representative must be able and willing to follow study procedures and instructions in order to maintain compliance throughout the study period.
• The patient or legally appointed and authorized representative must have read, understood and signed an Institutional Review Board/Ethics Committee (IRB/EC) approved Informed Consent or Assent Form.

Exclusion criteria

• Patient's use of prior or concomitant medication or medical treatments/procedures:

• Any investigational drug or therapy within 30 days.
• Systemic steroidal therapy within 30 days.
• Topical steroidal therapy within 14 days (Note: inhaled and ophthalmic products containing steroids are allowed).
• Systemic antibiotic therapy within 7 days.
• Currently receiving chemotherapy or radiation.
• Surgery within the previous 2 weeks (except for minor surgery, cosmetic or dental procedures as determined by the investigator).
• Started to take chronic medications (NSAIDs, antihistamines, etc.) at least 30 days prior to starting study medication.
• Patient's medical history includes:

• Cancer that is currently undergoing treatment.
• History of chronic and severe vitamin, mineral, or protein deficiency.
• Current systemic infection.
• HIV/AIDS.
• Non-EBS skin disease (e.g., psoriasis, atopic dermatitis, eczema, sun damage, etc.), or condition (e.g., sunburn) that, in the opinion of the investigator, might put the patient at undue risk by study participation or interferes with the study medication application or the study assessments.
• An illness (e.g., neurological, cardiovascular, respiratory, hepatic, renal, or metabolic disease), condition, or situation that in the opinion of the principal investigator is likely to interfere with the patient's participation in or completion of the study.
• Factors present in the patient and/or his/her legal representative that could interfere with study compliance such as inability to attend scheduled study visits or to perform study protocol procedures.
• Patient is a member of the investigational team or his/her immediate family.
• Other unspecified reasons that, in the opinion of the Investigator, make the patient unsuitable for enrollment.