STANFORD, CA. – A collaborative study by US and Brazil scientists has demonstrated potent activity by Riptide’s RP557 among fungal pathogens designated as high priority by the World Health Organization.
Writing in Microbiology, a team led by Dr. David Stevens of Stanford University and Dr. Melissa Xavier of the Mycology Laboratory, Federal University of Rio Grande, evaluated the activity of RP557 in a wide portfolio of fungal pathogens, including many Cryptococcus, Candida, and Fusarium species. RP557 was found to have promising activity against over two-thirds of priority pathogens.
The peptide showed particularly impressive activity as a monotherapy in Cryptococcus, Fusarium, Mycetoma, and Dermatophyte species. It showed significant activity in combination with current therapeutics in Candida auris, a growing threat worldwide that is resistant to most drugs.
Principal author Dr. Stevens is among the world’s foremost researchers in fungal disease. Stevens commented, ‘we were motivated to conduct this investigation by our previous findings that RP557 has broad-spectrum efficacy and does not induce antibiotic resistance, a growing barrier to the treatment of many of these diseases. It also readily penetrates the biofilm that fungal pathogens use as protection.’
Dr. Stevens noted that the results were particularly impressive with pathogens that are endemic to subtropical and tropical environments. Among these, Chromoblastomycosis and Eumycetoma are disfiguring diseases with few effective therapies currently available, and are in the WHO list of neglected tropical diseases. Stevens noted, ‘millions of people suffer from these diseases, and the current treatments have substantial adverse effects. Similarly, sporotrichosis is endemic in Brazil and is spreading to other countries. We need effective answers to these global health challenges, and RP557 may become one of these answers.’
The paper, entitled ‘Antifungal activity of the antimicrobial peptide RP557 against priority fungal pathogens,’ is available at https://doi.org/10.1099/mic.0.001663
Riptide Bioscience, Inc., with laboratories in Vallejo, California, maintains an intensive program of research into peptide-based therapeutics. Contact: info@riptidebio.com