PolyMedix Presents New Data on Its Defensin-Mimetic Antibiotics at 52nd Annual ICAAC
Presentations Include Additional Analysis of Brilacidin Phase 2 Clinical Data
RADNOR, Pa., Sept. 11, 2012 (GLOBE NEWSWIRE) -- PolyMedix, Inc. (OTCBB: PYMX), a biotechnology company focused on developing innovative approaches to transforming the treatment of infectious diseases, today announced that the Company presented data on its defensin-mimetic antimicrobial compounds at the 52nd Annual Meeting of the Interscience Conference on Antimicrobial Agents and Chemotherapy (ICAAC) in San Francisco, CA. The presentations included results of the first Phase 2 clinical study of PolyMedix's lead defensin-mimetic, brilacidin (PMX-30063), which showed high clinical response rates in patients with acute bacterial skin and skin structure infections (ABSSSI) caused by Staphylococcus aureus.
"We are excited to present data at ICAAC from our first Phase 2 study with brilacidin and our preclinical studies with other defensin-mimetic compounds," said Dr. Richard Scott, Vice President of Research at PolyMedix. "We are proud to be the pioneers in developing defensin-mimetics, a novel class of antibiotics with a distinct mechanism of action from currently known drugs. We look forward to advancing the development of these innovative compounds and exploring their potential to treat a wide range of infectious diseases."
Brilacidin Phase 2 ABSSSI Data
In a multicenter, double-blind dose-ranging Phase 2 study, 215 patients with ABSSSI (Acute Bacterial Skin and Skin Structure Infections) and evidence of Staph aureus were randomized into three treatment groups and given a low (0.40 mg/kg day 1 + 0.30 mg/kg days 2-5), medium (0.75 mg/kg day 1 + 0.35 mg/kg days 2-5) or high (1.0 mg/kg day 1 + 0.35 mg/kg days 2-5) dose of brilacidin for 5 days followed by 2 days of placebo, or daptomycin for 7 days. Investigators examined response rates at days 2-3, 7-8, 10-14 and 28. A patient met the response criteria if there was a significant reduction in lesion size at all four assessment visits. As indicated in the table below, the results of this study showed that clinical response rates were high across all treatment groups and similar to daptomycin:
Study
Visit
| Low dose
n=40
| Medium dose
n=35
| High dose
n=39
| Daptomycin
n=47
| Day 2-3
| 97.5%
| 91.4%
| 92.3%
| 91.5%
| Day 7-8
| 92.5%
| 94.3%
| 97.4%
| 95.7%
| Day 10-14
| 92.5%
| 91.4%
| 97.4%
| 95.7%
| Day 28
| 87.5%
| 80.0%
| 97.4%
| 93.6%
|
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|
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| Data based on per protocol patient population.
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| In the study, brilacidin was safely administered and adverse events appeared to be exposure-related. Aside from mild, transient numbness and tingling, for which no patient discontinued treatment, the overall adverse event rates were under 10% in each dose group. Rare cases of transient systolic blood pressure elevations occurred in 6 of the 160 (3.8%) patients treated with brilacidin. Of the six patients, three were in the high dose group. The one patient in the low dose group that experienced high blood pressure was reported as having pre-existing hypertension.
PolyMedix scientists believe that the attributes of brilacidin, including rapid bactericidal action, efficacy driven by exposure and not time, long half-life, and a long post-antibiotic effect, support exploring shorter courses of treatment in future clinical studies.
"We are very encouraged by the results of the Phase 2 study for this new class of antibiotics, and believe the continued analyses support the further development of this compound," commented Dr. Daniel Jorgensen, Senior Vice President of Clinical Development and Chief Medical Officer at PolyMedix. "There are many aspects to brilacidin which we believe will distinguish it from other antibiotics, most particularly, its low potential for the development of bacterial resistance, as observed in our preclinical studies. Resistant bacterial infections are a growing medical problem in need of novel solutions. We are looking forward to advancing the clinical development of brilacidin and exploring shorter courses of therapy in our Phase 2B clinical trial."
Additional data presented by PolyMedix at ICAAC included:
Nonpeptidic Mimics of Host Defense Proteins (HDP) as Antimicrobial Agents for E. coli 0104:H4, Campylobacter spp. and Other Foodborne Pathogens In preclinical studies, HDP mimics were shown to have potent and rapid bactericidal activity against some of the most prevalent foodborne pathogens, including E. coli and Campylobacter species, among the most common causes of foodborne disease, bacterial diarrheal illness, and deaths. 30 HDP mimics, from 6 structural series, were broadly active against at least 6 of the 8 foodborne pathogens screened and many of the compounds (26) showed low cytotoxicity against mammalian cells. Animal studies are underway to identify lead compounds for the treatment of foodborne illnesses.
Nonpeptidic Mimics of Host Defense Proteins as Antimicrobial Agents for Category A and B Biowarfare Pathogens Structurally-diverse HDP mimics demonstrated potent antimicrobial activities against biowarfare pathogens in vitro and in vivo, supporting further development of novel defense technologies.
Small, Nonpeptidic Mimics of Host Defense Proteins Exhibit Potent Killing Activity Against Gram-positive and Gram-negative Biofilm Cultures Compounds that mimic the activity of HDPs were found to be active against Gram-positive and Gram-negative biofilm cultures, with low cytotoxicity. Their effectiveness supports further evaluation of these and other HDP mimics as therapeutic agents for treatment of biofilm-associated infections.
Activity of PMX-30063 Against Drug Resistant Staphylococci Brilacidin (PMX-30063) exhibited potent activity against multi-drug resistant S. aureus and coagulase-negative staphylococci and six isogenic strain pairs of daptomycin-sensitive and resistant MSSA and MRSA, demonstrating brilacidin is highly active in vitro against multi-drug resistant staphylococci.
Metabolism and Excretion of PMX-30063: A Novel Class of Antibiotics The majority of brilacidin (PMX-30063) was eliminated unchanged via fecal route and there was no indication of metabolism in liver or kidney.
The above mentioned presentations are available on the Company's website at investors.polymedix.com.
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