Topical Sirolimus for the Treatment of Pachyonychia Congenita (PC)

Inclusion Criteria:

Subjects must:

   - Be capable of understanding the purpose and risks of the study and sign a written
   Informed Consent Form (ICF)

   - Be male or female ≥ 16 years of age at the time of the screening visit

   - Have a confirmed diagnosis of PC by genotyping (e.g., familial) and clinically
   correlated painful keratoderma.

   - Have roughly symmetrical calluses of similar severity on the plantar surface of both
   feet

   - Women of childbearing potential must have a negative serum pregnancy test

   - Subjects, whether male or female, with reproductive potential and who are sexually
   active must agree to use double-barrier contraception methods

Exclusion Criteria:

A Subject with any of the following criteria is not eligible for inclusion in this study:

   - Use of other investigational drugs within 30 days of the screening visit and/or has
   not recovered from any side effects of prior investigational drugs or procedure in the
   affected area (e.g., a biopsy)

   - Significant condition in the dermatologic treatment area such as trauma, or nonhealing
   chronic wound

   - Pregnant or nursing (lactating) female, or a positive serum pregnancy test

   - Active infection either systemic or local near the site of treatment requiring chronic
   or prolonged use of antimicrobial agents

   - Known immunodeficiency including: Hepatitis A; Hepatitis B; Hepatitis C; Human
   Immunodeficiency Virus (HIV)

Prior and Current Treatment

   - Unable to be discontinued from drugs known to either be inducers or inhibitors of
   CYP3A4/5 enzymes

   - Unable to be discontinued from drugs known to be P-glycoprotein inhibitors