This is a prospective, single center, randomized, double-blinded, placebo-controlled, exploratory phase I clinical trial in healthy male subjects to investigate the safety and tolerability of the cytokine based gel APOSEC™. The proof of safety and tolerability of APOSEC™ is the primary objective. The secondary objective is to measure the extent of wound healing of APOSEC™.

APOSEC™ is a human product derived from lyophilized conditional medium of peripheral blood mononuclear cells (PBMC) following 24 hours cultivation after irradiation with 60Gy. The soluble factors produced by these factors (secretome) have regenerative functions and enhance wound healing due to the activation of signaling cascades involved in the cell migration, proliferation and cell survival. The product also possesses strong angiogenic properties as well in vivo and in vitro. APOSEC™ is intended for topical use only, to promote healing of wounds in association with standard wound care. Standard wound care includes initial debridement, avoidance and treatment of wound related infections and a non-weight-bearing regime to decrease the pressure on the wound.

The verum APOSEC™ is processed as lyophilisate and resuspended in Nugel for the final formulation. It will be compared with a placebo, a cell-free parallel produced cell-free control lyophilisate that is finally formulated in Nugel as well.

10 eligible healthy volunteers will consecutively be allocated to 2 different dose groups of APOSEC™ in a dose escalation scheme. The first 5 subjects in group A receive the low dose of APOSEC™ (12.5*10^6 lyophilized PBMC/mL), the subsequent 5 subjects in group B will receive the high dose of APOSEC™ (25*10^6 lyophilized PBMC/mL). Each volunteer will receive both Verum and Placebo on two artificial wounds on the inner upper non-dominant arm. The location of application of the Verum and Placebo (proximal or distal) is subjected to randomization.

Inclusion Criteria:

• Healthy male subjects with 18-50 years of age at the day of inclusion
• Written informed consent will be obtained prior to screening examination
• BMI of 19-27 (extremes included)
• Subjects are in good clinical and mental health as established by medical history, physical examination, vital signs, electrocardiogram, results of biochemistry, hematology, virology and urine analysis at the Screening Visit

Exclusion Criteria:

• Lack of willingness or capacity to co-operate appropriately
• Regular use of medications
• History of malignancies
• History of wound healing abnormalities
• Chronic dermatological disease
• History of chronic autoimmune diseases such as rheumatoid arthritis, inflammatory bowel disease, diabetes mellitus, Lupus erythematodus
• Tattoos in the region of planned punch biopsy
• Positive HIV serology or evidence of active hepatitis
• Allergy requiring medical treatment within 4 weeks before study initiation
• Active infection of fever > 38°C within 7 days prior randomisation
• Blood donation within 4 weeks before study initiation
• Clinically relevant abnormalities in the laboratory testing, vital signs, ECG or physical examination
• Participation in another clinical trial with an investigational day within 4 weeks before study participation