Viron Therapeutics Inc. reported results from a Phase IIa clinical trial evaluating VT-111 (Serp-1), an anti-inflammatory protein derived from the
Myxoma virus. The results were presented by Dr. Jean-Claude Tardif, Director of the
Research Centre at the Montreal Heart Institute, during the Scientific Sessions of the
American Heart Association (AHA) 2009 conference. VT-111 met both primary and secondary endpoints of the trial, which was designed to evaluate the
safety and biological activity of VT-111 in
Acute Coronary Syndrome (ACS) patients receiving coronary
stents.
"The positive safety and efficacy data from this trial provide a strong scientific rationale for moving forward with this novel drug in ACS and potentially other indications," said Dr. Tardif. "There were also no subsequent major adverse cardiac
events in the high dose group, which correlates well with VT-111's impact on two prognostic cardiac
biomarkers/order_t/'>biomarkers, Troponin I and CK-MB, whose predictive value have been demonstrated in other studies. It may also be possible for VT-111 to have an even greater impact if delivered in a larger dose than the low dose of 15 micrograms per kilogram ((micro)g/kg) tested in this trial."
In this double-blind,
placebo-controlled Phase IIa trial, 48 patients received intravenous doses of placebo or VT-111 once daily for three days starting immediately before their stenting procedure. Subjects were then followed for three days in the hospital and returned at two weeks, four weeks, three months, and six months for evaluation of safety and a variety of inflammatory and cardiac
biomarkers.
A statistically significant, dose-dependent reduction in levels of the cardiac damage
biomarker Troponin I was associated with VT-111 treatment at eight, 16, 24, and 54 hours following the initial dose. The VT-111 treated patients also showed a statistically significant reduction in the cardiac damage biomarker creatine kinase myocardial biomarker (CK-MB) at eight, 16, and 24 hours. VT-111 also showed strong trends toward reducing Major Adverse Cardiac Events (MACE, a clinical endpoint comprised of
myocardial infarction, revascularization, coronary artery bypass graft (CABG) or death) in the higher dose group, with no MACE events at the six month follow-up, compared to the placebo group, which had (greater than)18% MACE.
Previously published studies have shown that a reduction in the rise of Troponin I and/or CK-MB in the first 24 hours after stent placement is predictive of whether a patient will experience a subsequent clinical event.
The study showed no difference between the treatment and placebo groups for the key safety measures, including coagulation markers and adverse events. In-stent plaque area and lumen area, as assessed by intravascular
ultrasound at six months, were similar for both groups. VT-111 demonstrated no drug-related adverse events and no neutralizing
antibodies (low
immunogenicity) in the patient population.