RADNOR, Pa., Jan. 14, 2013 (GLOBE NEWSWIRE) -- PolyMedix, Inc. (OTCBB:PYMX), a biotechnology company dedicated to developing novel treatments for infectious diseases with defensin-mimetic antimicrobial agents, today announced that pre-clinical data demonstrating activity of the Company's defensin-mimetic antimicrobial compounds against the parasite that causes malaria, Plasmodium falciparum, were published in the December issue of Cell Host and Microbe, a peer-reviewed scientific journal.
The article entitled, " Platelet Factor 4 Activity against P. falciparum and Its Translation to Nonpeptidic Mimics as Antimalarials" is the result of a collaboration between PolyMedix and the University of Pennsylvania, Drexel University and John Hopkins University.
PolyMedix's library of defensin-mimetic antimicrobial compounds were screened to identify those capable of selectively killing the P. falciparum parasite without showing signs of cytotoxicity toward mammalian cells. A number of PolyMedix's defensin-mimetic compounds showed a high degree of activity against both drug-sensitive and drug–resistant parasites and act in a similar fashion to human platelet factor 4 (hPF4), a naturally-occurring protein. hPF4 is produced by platelets and has been observed to kill the malaria parasite in infected red cells without harming the red cell itself. The defensin-mimetic compounds and hPF4 appear to act via the same unique mechanism, which is distinct from other anti-malarial agents, by rapidly destroying the digestive vacuole of the parasite essentially starving it of food and releasing digestive enzymes. Furthermore, in the study, the mimetic compounds acted with greater speed and potency than the natural hPF4 protein, suggesting an advantage of the PolyMedix protein-mimetic approach.Two of the lead defensin-mimetic compounds were tested in mouse models of malaria. Both compounds significantly decreased parasitic growth and greatly improved survival rates, providing further confirmation of the potential of defensin-mimetics as antimalarial agents. "Our work shows that it may be possible to mimic a natural mechanism of the innate immune system with drug-like small molecules that we believe could be optimized to create potent, selective, potentially less toxic, and cheaper to make antimalarials," commented Dr. Doron Greenbaum, assistant professor of pharmacology at the Perelman School of Medicine, University of Pennsylvania. "Targeting parasite membranes rather than proteins using PolyMedix's defensin-mimetics represents a highly innovative and novel approach for treating parasitic diseases."