Brilacidin is a nonpeptidic anti-infective in a new class of defensin mimetics used for the research of eye infections.

Brilacidin is more potent for Gram-positive bacteria (except SV) than Gram-negative bacteria. Brilacidin acts primarily on the bacterial cell membrane by depolarization. Brilacidin has Gram-positive in vitro activity; topical Brilacidin 0.5% is minimally irritating; and Brilacidin 0.5% was equally efficacious as Vancomycin (VAN) in a methicillin-resistant S. aureus (MRSA) keratitis model when the corneal epithelium is removed. Both Staphylococcus aureus (SA) and Staphylococcus epidermidis (SE) have the lowest minimum inhibitory concentrations among the bacterial groups. The MIC90s to Brilacidin for Streptococcus pneumonia (SP), Streptococcus viridians (SV), Moraxella (MS), Haemophilus influenza (HI), Pseudomonas aeruginosa (PA), and Serratia marcescens (SM) are 4, 32, 256, 32, 16, and 128-fold higher, respectively than SA and SE.

Brilacidin (0.5) is determined to be Nonirritating based on their Maximum mean total scores (MMTS) values. Brilacidin 1% is determined to be Mildly Irritating (23.0), Brilacidin 0.5% (6.5), and Brilacidin 0.25% (4.0) are determined to be Minimally Irritating, while Brilacidin 0.1% (2.0) and TBS (1.0) are determined to be Practically Nonirritating and 0.01%. Brilacidin demonstrates dose-dependent ocular toxicity after 7 topical instillations (every 30?min for 3?h) in the NZW rabbit ocular toxicity model.