study of a novel therapeutic vaccine for hepatitis c virus

Conditions: Hepatitis C

Summary: hcv002tv is a phase i study to ascertain the safety and immunogenicity of a novel vaccine against hepatitis c virus (hcv) in chronically infected patients. the vaccine is based on the sequential delivery, by intramuscular route, of two different adenoviral vectors, of chimpanzee and human origin respectively, bearing the same genetic information for hcv antigens (ns region). the two recombinant vaccine vectors, called adch3nsmut and ad6nsmut, are weakened and unable to multiply within the body; they are designed to induce an immune response against hcv proteins. adch3nsmut and ad6nsmut are being used in the ongoing hcv001 study in healthy volunteers with very good safety and immunogenicity results. hcv002tv is a dose-escalation study; the adch3nsmut is administered as priming vaccination and ad6nsmut as boosting vaccination. the trial includes: * arm a, in which vaccinated patients are into interferon-ribavirin therapy (the gold standard therapy for hepatitis c); * arm b, in which vaccinated patients are not into therapy.


Eligibility criteria:
inclusion criteria: * the patient must satisfy all the following criteria to be eligible for the study: * hcv infected with genotype-1 infection * adults aged 18 to 65 years (inclusive) * in arms a1-a3 patients will only be vaccinated if they have a \>2log drop in viral load at week 12 of ifn-alpha and ribavirin therapy. vaccination will then occur at week 14 into ifn-alpha and ribavirin therapy. * resident in or near the trial sites for the duration of the vaccination study * able and willing (in the investigator's opinion) to comply with all study requirements * for women of child bearing potential, willingness to practice continuous effective contraception during the study and a negative pregnancy test on the day(s) of vaccination * for men to use barrier contraception until three months after the last vaccination * written informed consent exclusion criteria: * the patient may not enter the study if any of the following apply: * participation in another research study involving an investigational product in the 30 days preceding enrolment, or planned use during the study period * prior receipt of a recombinant simian or human adenoviral vaccine * clinical, biochemical, ultrasonographic, or liver biopsy (histology) evidence of cirrhosis or portal hypertension * any confirmed or suspected immunosuppressive or immunodeficient state, including hiv infection; asplenia; recurrent, severe infections and chronic (more than 14 days) immunosuppressant medication within the past 6 months (inhaled and topical steroids are allowed) * patients likely to have been infected with hcv within the last 12 months * history of allergic disease or reactions likely to be exacerbated by any component of the vaccine, e.g., kathon * patients who failed to respond (non-responders) to previous ifn-alpha monotherapy * patients who received ifn-alpha and ribavirin in the past and who were non-responders or relapsed during or after therapy * history of clinically significant contact dermatitis * for arm a, patients must be treatment naïve (i.e. never have had previous ifnα or ribavirin treatment). arm b may include patients who have previously been treated for hcv and failed to achieve a sustained virological response (defined by undetectable hcv by pcr at 6 months post cessation of treatment) * any history of anaphylaxis in reaction to vaccination * pregnancy, lactation or willingness/intention to become pregnant during the study * history of cancer (except basal cell carcinoma of the skin and cervical carcinoma in situ) * any other serious chronic illness requiring hospital specialist supervision * suspected or known current alcohol abuse as defined by an alcohol intake of greater than 42 units every week * current suspected or known injecting drug abuse * seropositive for hepatitis b surface antigen (hbsag) * seropositive for hiv (antibodies to hiv) at screening * seropositive for simian adenovirus 3 (antibodies to adch3) at titres \>200, at screening * seropositive for human adenovirus 6 (antibodies to ad6) at titres \>200, at screening * any other significant disease, disorder or finding, which, in the opinion of the investigator, may either put the patient at risk because of participation in the study, or may influence the result of the study, or the patient's ability to participate in the study * any other finding which in the opinion of the investigators would significantly increase the risk of having an adverse outcome from participating in the protocol * individuals who have had a temperature \>38°c in the 3 days preceding vaccination.

Keywords: hepatitis c hcv adenovirus vaccine