04 Jul 2008
Tripep AB, reported additional interim results from its ongoing phase I/II clinical study of its ChronVac-C® therapeutic DNA vaccine, which is delivered using Inovio's electroporation-based DNA delivery system.
These preliminary results are from the first two patients in the intermediate dose group to complete treatment against hepatitis C virus infection. Samples taken before, during and after treatment showed that the viral levels in blood decreased up to 87% and 98%, respectively, during treatment. Simultaneous activation of the patients' T-cell responses to the hepatitis C virus was recorded in conjunction with the viral load reductions. Inovio's electroporation delivery technology is intended to enhance the potency of DNA vaccines against cancers and infectious diseases.
ChronVac-C® is a therapeutic vaccine given to individuals already infected with the hepatitis C virus with the aim of clearing the infection from the liver by boosting the body's immune response against the virus. This clinical study is being conducted at the Infectious Disease Clinic and Center for Gastroenterology at the Karolinska University Hospital in Huddinge and Solna, respectively, in Sweden. The intended enrollment of 12 patients is being divided into three dose groups with increasing doses of ChronVac-C. Each patient receives four vaccinations one month apart. After the last vaccination, patients are followed for another six months. The study's main purpose is to assess safety. It is also testing whether the treatment boosts the immune response (immunogenicity) to HCV and its effect on virus replication in the liver. If the patient is completely virus-free six months after completing treatment, he/she will be considered cured.
In the group treated with the low dose of ChronVac-C, transient activation of T-cell responses was recorded but no reduction of viral load. In the group treated with the intermediate dose, T-cell responses were recorded simultaneously with clear reductions in the serum levels of hepatitis C virus, suggesting that the therapy is dose-dependent. No severe adverse events have been recorded. All three patients in the high dose group have started therapy and we expect results from this group during the fall.
Avtar Dhillon, MD, Inovio's president and CEO, stated: "Recognizing that this is still a very limited patient population and data set, we are encouraged by the results of this hepatitis C virus phase I/II clinical study. Existing treatments are hard on patients, often described as being similar to chemotherapy, and are only effective in roughly half of patients treated. We are pleased that to date this therapy has not produced these chemotherapy-like side effects nor serious adverse events and, without yet reaching the highest dose levels, is producing positive results. The fact that there may be a dose-dependent correlation between T-cell responses generated and reduction in hepatitis C viral load may position ChronVac-C, in which we have partial ownership, to potentially play a role as a first-line therapy or as an adjunct to existing therapies. We look forward to the continuing clinical assessment of this promising DNA vaccine candidate."
Article URL: http://www.medicalnewstoday.com/articles/113964.php
