IXODES GmbH intends to develop SHB001, an azithromycin dermal formulation in order to prevent Lyme disease at early stages of infection after tick bite.

In this study two consecutive cohorts will be treated:

• Cohort 1: 8 volunteers
• Cohort 2: 24 volunteers, divided into 3 groups of 8 subjects each

The study will be conducted in the following three phases:

1. Treatment of cohort 1: The aim is to establish the maximal tolerated dose (MTD) for a local treatment with azithromycin dermal formulation.

   1. Treatment of cohort 1 with azithromycin dermal formulation and follow up
   2. Assessment of local safety within the 7 days following the first treatment
   3. The maximal tolerated dose (MTD) will be determined

2. Treatment of cohort 2: The aim is to confirm the local tolerance of the selected doses and to evaluate the local skin and plasma concentration of azithromycin after application of SHB001 dermal formulation.

   1. Treatment of cohort 2 with azithromycin dermal formulation at maximal tolerated dose (MTD), with a dose one or more concentrations lower than maximal tolerated dose (MTD) and with placebo
   2. Skin biopsies of treated skin areas will be taken for the PK assessment

3. Study completion examination

Main inclusion criteria:

• Male or female healthy volunteers, age 18 - 70 years

Main exclusion criteria:

• A known hypersensitivity against azithromycin, erythromycin or any of the macrolide antibiotics
• A known hypersensitivity against lidocaine
• Treatment by any route with any macrolide antibiotic within the last 2 month