BLUE BELL, Pa., April 2, 2013 /PRNewswire/ -- Inovio Pharmaceuticals, Inc. (NYSE MKT: INO) today announced the release of preliminary clinical trial results by its collaborator ChronTech AS of their open label phase II clinical study of ChronVac-C®, ChronTech's vaccine to treat hepatitis C virus (HCV) infection. The study investigated the use of the ChronVac-C DNA vaccine administered with Inovio's MedPulser TM-DDS electroporation device followed by a drug regimen (ribavirin + PEG-interferon-a) in chronic HCV positive subjects. These initial results do not show a statistically significant difference so far between treatment outcomes of the vaccinated and non-vaccinated groups. The vaccinated group did display an excellent safety profile.
In this 29 patient phase II study, 17 patients were treated with two monthly vaccinations of ChronVac-C (500 ug) followed by interferon and ribavirin. In the control arm, 12 patients were treated with interferon and ribavirin alone. ChronTech has now made a first analysis 12 weeks after treatment. HCV viral load reduction or elimination is assessed by measuring HCV RNA levels. At treatment week 12, 71% of the pre-vaccinated group had less than 15 international units of HCV RNA compared to 58% in the non-vaccinated group; 65% were HCV RNA negative compared to 58% in the non-vaccinated group. There were no serious adverse events and the number of patients with moderate adverse events was statistically lower in the pre-vaccinated group than in the non-vaccinated group (p<0.05, Fishers exact test). There was no difference in mild adverse events between the groups.
In 2007, ChronTech initiated its phase I dose escalation (167, 500, 1500 mg) study using its ChronVac-C DNA vaccine targeting genotype 1a and NS3/4A antigens delivered with Inovio's MedPulser device. The treatment regimen of four vaccinations delivered with electroporation demonstrated transient reduction in viral load. In that study, a group of eight patients were subsequently treated with standard of care ribavirin plus PEG-interferon-a. Of this group, six patients (75%) achieved a complete early viral response (cEVR) and a sustained viral response (SVR), an encouraging result compared to typical medical observations of 40-50% response rates with the ribavirin-interferon drug regimen alone in genotype 1 patients. In contrast to the previous study, in this subsequent phase II study only two DNA vaccine administrations at the medium dose level used in the phase I study were used to assess the potential for a clinically meaningful result.