This is a phase I trial to evaluate tacrolimus blood levels after topical application of tacrolimus twice daily on healthy skin.

The purpose of this trial is to assess the safety of a topical formulation of tacrolimus.

Tacrolimus is commonly used in T-cell medicated diseases. It is expected that 24 subjects will be enrolled in the trial and will be assigned to receive topical application of tacrolimus twice daily for 14 days.

Key Inclusion Criteria:

• Healthy male and female subjects between 18 and 60 years of age, with a body mass index (BMI) between 18.5 and 30 kg/m2 inclusive
• Female subjects of childbearing potential must be confirmed not pregnant at the screening visit and use highly effective contraception during the trial.

Key Exclusion Criteria:

• Treatment with the following medications: Topical immunosuppressive drugs (e.g. tacrolimus, corticosteroids), systemic immunosuppressive/immunomodulating drugs
• Extensive UV radiation or sunlight on the application sites
• Skin diseases
• Wounded or damaged skin at the application site
• Immunosuppressed or immunocompromised individuals
• Renal or hepatic impairment or insufficiency
• Known allergy or known or suspected hypersensitivity to any component(s) of the topical formulation of tacrolimus
• Female subjects who are pregnant or lactating