However, the potential benefits of erythropoietin must be weighed against its potential side effects, the fact that its use in HCV therapy is

not approved by the FDA, and its considerable cost. If a PI treatment–limiting adverse event occurs, PegIFN and RBV can be continued provided SCH727965 chemical structure that an on-treatment response had occurred. There are no data to help guide substitution of one for the other HCV PI. If a patient has a serious adverse reaction related to PegIFN and/or RBV, the PegIFN and/or RBV dose should be reduced or discontinued. If either PegIFN and/or RBV are discontinued, the HCV PI should be stopped. Additional information on management of other adverse events can be found in the package insert. Because patients with CHC frequently receive medications in addition to those used to treat HCV infection, and because the PIs can inhibit hepatic drug-metabolizing enzymes such as cytochrome P450 2C (CYP2C), CYP3A4, or CYP1A, both BOC and TVR were studied for potential interactions with a number of drugs likely to be coadministered. These included statins, immune suppressants, drugs used to treat HIV coinfection, opportunistic infections, mood disorders, click here and drug addiction support medications. Both BOC and TVR, were noted to cause interactions with several of the drugs examined, either increasing

or decreasing pharmacokinetic parameters. It is particularly important, therefore, that the medical provider review this information as listed in the package insert for each of the drugs before starting treatment for CHC. This information Cepharanthine can be obtained at the FDA Web site: www.accessdata.fda. gov/scripts/cder/drugsatfda/index.cfm. Other helpful sites are: http//:222.drug-interactions.com and www. hep-druginteractions.org Emergence of antiviral-resistant variants during PI-based therapy has been observed during all trials and is associated with virological failure and relapse (Tables 2 and 3). Mutations that confer either high or low level resistance to BOC and TVR cluster around the catalytic site of the NS3/4A serine protease. Similar

variants were detected in both BOC and TVR-treated subjects, suggesting that some degree of cross-resistance exists between the two PIs. In both phase 3 studies, sequence analysis of the NS3/4A region was performed in all subjects at baseline and for all subjects who failed to achieve an SVR. Antiviral resistant variants were detected in a small proportion of patients at baseline, 7% in the BOC studies and 5% in the TVR trials, but did not appear to impact response to either PI.25, 26 Therefore, there is currently no clinical indication for baseline resistance testing. Among treatment-naïve patients receiving a BOC regimen, antiviral resistant variants developing during treatment were observed overall in 16% of patients (Table 2).