Immunogenicity of branched polyethylene glycol modified interferon alpha

To assess the immunogenicity of Peginterferon alpha-2 b(Pegberon) and its effect on the efficacy and safety in phase III clinical trial, by comparing it with the control drug Pegasys.

770 patients were recruited in total. 509 were treated with Pegberon plus ribavirin and 261 were treated with Pegasys plus ribavirin. After treatment of 12 and 24 weeks, plasma samples were collected from individual patients for detecting the anti-therapeutic antibodies (ATA) and hepatitis C RNA(HCV RNA), to evaluate the production of antibodies and their adverse effect on the efficacy and safety of the treatments. With data obtained from the treatments with Pegberon or Pegasys, gross comparison analysis was performed.

The incidence of treatment-induced neutralizing antibodies (NAb) of Pegberon group (0.7%, 3/454) was significantly lower than Pegasys group (5.0%,12/238)(p < .001). Among all patients, the rates of sustained virological response 24 (SVR24) were significantly different between baseline ATA positive (60.7%,34/56) and baseline ATA negative patients (76.2%,544/714)(p = .010), between baseline NAb positive (36.0%,9/25) and baseline NAb negative patients (76.4%,569/745)(p < .001) and between induced ATA positive (72.7%,40/55) and sustained ATA negative patients(84.0%,492/586)(p = .034). The incidence of potential immunogenicity-related adverse reactions (AR) showed no significant difference between Pegberon (55.6%,283/509) and Pegasys groups (53.6%,140/261)(p = .605) and the profiles of these AR were also similar between the two groups.

The incidence of treatment-induced Nab in Pegasys group was significantly higher than the Pegberon group. Baseline ATA, induced ATA and baseline NAb all affected the efficacy. The profiles of potential immunogenicity-related AR were similar between two drug groups, indicating the immunogenicity had no significant adverse effect on safety.