Tripep completes clinical trial of ChronVac-C for Hepatitis C virus treatment

All samples from the 12 patients with chronic Hepatitis C genotype 1 treated with Tripep’s therapeutic vaccine ChronVac-C® have now been collected. The treatment was found to be safe, immunogenic and had transient effects on the serum levels of hepatitis C virus. This provides a proof-of-concept for the therapeutic strategy. In addition, early data from three patients who have initiated standard of care treatment after completing the clinical trial have experienced a rapid loss of the virus, implying a possible role for ChronVac-C® in combination therapies. Tripep will therefore pursue clinical development of ChronVac-C® along two lines, the current ChronVac-C® as an addition to standard of care, and a 2nd generation improved ChronVac-C® as a monotherapy. GMP production and preclinical safety testing of the 2nd generation ChronVac-C® should start in the spring of 2010. Finally, Tripep has filed an application with the Swedish Medical Products Agency to give the last three patients in the finalized study a fifth booster dose 6-12 months after the fourth dose.

All patients have now completed treatment with ChronVac-C®. A first summary of available data (immunological analysis of some samples are still under way) shows that the treatment was found to be safe, immunogenic and had transient effects on the serum levels of hepatitis C virus. In the lowest (167 µg) dose group, no reductions in serum levels of HCV RNA were noted and no immune responses lasting ≥ 1 month were detected. In the 500 µg dose group 2/3 patients showed transient reductions in serum levels of HCV RNA (up to -1,5log10) and in the same two patients T cell responses to the vaccine lasting ≥ 1 month were activated. In the 1500 µg dose group 3/6 patients showed transient reductions in serum levels of HCV RNA (up to -2,4log10) and in two of these three patients T cell responses to the vaccine were obtained that lasted ≥ 1 month. This provides a proof-of-concept for the therapeutic strategy and supports further clinical development. In addition, early data from three patients who now have initiated standard of care treatment after completing the clinical trial have experienced a rapid loss of the virus, possibly suggesting a role for ChronVac-C® in combination therapies. This data will be monitored for as many patients as possible during the coming year to obtain a more solid data base. Tripep will therefore pursue clinical development of ChronVac-C® along two lines, the current ChronVac-C® as in as an addition to standard of care and an improved 2nd generation ChronVac-C® as a monotherapy. Preclinical safety testing of 2nd generation ChronVac-C® should start in the spring of 2010. Finally, Tripep has filed an application with the Swedish Medical Products Agency to give the last three patients a fifth booster dose.

“We are extremely pleased with the outcome of the clinical trial in particular considering that this was the first time ever that a DNA vaccine was delivered using in vivo electroporation against an infectious disease. We now have an excellent basis from which we continue clinical development and are looking forward from the additional exciting clinical data from the patients when they undergo standard of care therapy. We will report these data as they become available to us. Following this success we will now actively expand our therapeutic vaccine program also into chronic hepatitis B were we during 2009 have generated highly promising therapeutic vaccine candidates” says Tripeps CEO Anders Vahlne.