VX-222: Additional Phase II data

Vertex reported interim data from 46 treatment-naïve patients with chronic HCV genotype 1a or 1b infection who were receiving twice-daily 400 mg VX-222 plus Incivek telaprevir and ribavirin in the interferon-free arms of the open-label, U.S. and New Zealand Phase II ZENITH trial. Of the 11 patients who were eligible to stop all treatment at week 12, 9 (82%) achieved an SVR defined as undetectable HCV RNA levels (<10 IU/mL) 4 weeks after the end of treatment (SVR4). All 5 evaluable patients with HCV genotype 1b infection achieved an SVR 12 weeks after the end of treatment (SVR12). SVR12 data for the 6 patients with HCV genotype 1a infection are not yet available. Patients with undetectable virus at weeks 2 and 8 were eligible to stop all treatment at week 12. Data from all 46 patients showed that rates of rapid (RVR) and complete early virologic response (cEVR), defined as undetectable virus at week 4 and 12 of treatment, respectively, were 74% and 83%.

Last year, Vertex reported data from 59 treatment-naïve patients with chronic HCV genotype 1 infection who were receiving twice-daily 100 or 400 mg VX-222 plus Incivek, peginterferon alfa-2a and ribavirin in the ZENITH trial (see BioCentury, April 4, 2011; Aug. 1, 2011; & Nov. 21, 2011). In 2010, Vertex discontinued the dual-therapy VX-222 plus Incivek arms after undisclosed pre-defined stopping criteria related to viral breakthrough were met (see BioCentury, Jan. 3, 2011). The ZENITH trial enrolled 152 patients. ...