A Safety and Tolerability Study of Topical PAT-001 in Congenital Ichthyosis

Congenital ichthyosis (CI) is a large, heterogeneous family of inherited skin disorders of cornification resulting from an abnormality of skin keratinization, such as scaling and thickening of the skin. Treatment options include keratolytic agents, which can abruptly lead to extensive shedding or peeling of scales. PAT-001 primarily acts as a keratolytic agent; thus, making it a potential drug candidate for the treatment of skin disorders associated with hyperkeratinization, such as CI. The current study intends to evaluate the safety and tolerability of PAT-001 in patients with CI of either the Lamellar or X-Linked subtypes.

The management of CI is a life-long endeavor, which remains largely symptomatic (i.e., emollients with or without keratolytics agents) and commonly focused on reducing scaling and/or skin lubrication with both systemic and topical treatments. A first-line therapy includes hydration and lubrication accomplished by creams and ointments containing low concentrations of salt, urea, or glycerol, which increase the water-binding capacity of the horny layer. Addition of keratolytics agents are used to decrease corneocyte cohesiveness, to promote desquamation, and to dissolve keratins and lipids (e.g., α-hydroxy acids, salicylic acid, high dose urea, propylene glycol, N-acetylcysteine, and retinoids). Systemic retinoid treatment is reserved for those patients refractory to topical agents because of long-term adverse effects and teratogenicity.

This is a two part, Phase 2, multicenter, proof-of-concept (POC) study of the safety and tolerability of PAT-001 for the treatment of Congenital ichthyosis (CI) in patients ages 12 years of age and older. Part 1 will be a double-blind, randomized, vehicle controlled, bilateral comparison of two treatments (PAT-001 \[0.1% or 0.2%\] vs. vehicle) for eight (8) weeks.

Part 2 will be a double-blind, active only treatment comparison of the two PAT-001 concentrations (0.1% or 0.2%) for an additional four (4) weeks. Subjects will have the option to participate in the pharmacokinetics (PK) portion of the study.

Eligibility Criteria:
Inclusion Criteria:

* Patients of either sex aged 12 years or older.
* Females of childbearing potential should use appropriate contraception. Women of childbearing potential must have a negative pregnancy test at screening and baseline visits.
* Patient and legal representative(s), if applicable, has provided written informed consent.
* Patient has congenital ichthyosis of either lamellar or X-Linked subtype.
* Patient has two contralateral comparable Treatment Areas (e.g., each arm is affected and treatments areas can be applied equally).
* Patient is, except for their ichthyosis, in good general health.

Exclusion Criteria:

* Patient is pregnant or breast feeding, or is planning to become pregnant during the study.
* Patient has inflammatory skin disease unrelated to ichthyosis.
* Patient is currently using concomitant retinoid therapy, within two weeks (topical) or 12 weeks (oral) of Visit 2/Baseline.
* Patient is currently taking concomitant immunosuppressive drugs, including systemic corticosteroids, within two weeks of Visit 2/Baseline.
* Patient is currently enrolled in an investigational drug or device study.
* Patient has used an investigational drug or investigational device treatment within 30 days prior to Visit 2/Baseline.
* Patient is unable to communicate or cooperate with the investigator due to language problems, impaired cerebral function, or physical limitations.
* Patient is known to be noncompliant or is unlikely to comply with the requirements of the study protocol (e.g., due to alcoholism, drug dependency, mental incapacity) in the opinion of the investigator.