Elise Burger, MD, PhD
University of California San Diego
San Diego, CA
2022 AARS Research Grant Recipient
Evaluation of a Rationally Designed, Targeted Allobiotic Bacteriotherapy Product in Adult Acne Vulgaris Patients
Abstract
Recent metagenomic sequencing has revealed distinct strains of C. acnes enriched in acne patients, with increased virulence factors. Antibiotic therapy is a mainstay of treatment for attempting to kill C. acnes, however antibiotic treatment nonspecifically kills bacteria and
may induce additional dysbiosis. In addition, long-term treatments generate resistant bacteria.
Antimicrobial peptides (AMPs) such as defensins and cathelicidins are important mediators to maintain the balance of epithelial microflora. Our studies indicate that the innate immune defense of the skin is mediated not only by antimicrobial peptides produced by our own cells, but also by antimicrobial molecules contributed by commensal staphylococcus species, such as Staphylococcus epidermidis and Staphylococcus capitis.
Recent studies from our group have shown that a strain of the commensal S. capitis produces
antimicrobial molecules targeted against C. acnes. This strain, S. capitis E12 (ScE12) is allobiotic, and was rationally selected because it can kill multiple isolates of C. acnes, including disease-associated strains, and does not kill other commensal skin bacteria. The goal of this proposed clinical trial is to evaluate the safety of S. capitis E12 as a topical acne treatment and evaluate its survival and ability to inhibit C. acnes on the skin. Our hypothesis is that targeted application of this allobiotic strain will safely decrease C. acnes levels found on the skin of acne patients, leading to an improvement in acne.
To address this hypothesis, we propose to conduct a small pilot phase I, double-blinded, vehicle-controlled clinical trial. In this study, participants will apply live S. capitis strain E12 once daily to the face for 12 weeks. The study population will be 12 patients between age 18-45 with acne vulgaris. This population will be randomized 2:1 (8 will receive ScE12 and 4 will receive vehicle alone). Investigators and subjects will be blinded to treatment. As a first-in-human trial this study will provide valuable safety data for ScE12.
The potency of ScE12 to kill C. acnes supports the statistical power to detect a decrease in C. acnes in a cohort of this size. The FDA has approved an IND (#27888) to conduct this currently unfunded study.