nt. More INCIVEK-treated subjects had decreases in lymphocyte counts to 499/mm3 or less (15% compared to 5%). Decreases in total white cell counts to 1,499/mm3 or less were comparable (8% compared to 5%). The incidence of decreases in absolute neutrophil counts to 749/mm3 or less was 15% in subjects treated with peginterferon alfa and ribavirin alone compared to 12% among those treated with INCIVEK combination treatment.
Platelets: Treatment with peginterferon alfa is associated with decreases in mean platelet counts. More patients treated with INCIVEK combination treatment had decreases in mean platelet values of all grades: 47% compared to 36% treated with peginterferon alfa and ribavirin alone. Three percent of INCIVEK combination treatment subjects had decreases to 49,999/mm3 or less compared to 1% of those treated with peginterferon alfa and ribavirin-treated alone.
Bilirubin: Forty one percent of INCIVEK-treated subjects compared to 28% of peginterferon alfa and ribavirin-treated subjects had all grade elevations in bilirubin levels; 4% and 2% of subjects, respectively, had greater than or equal to 2.6 × ULN elevations. Bilirubin levels increased most steeply during the first 1 to 2 weeks of INCIVEK dosing, stabilized and between Weeks 12 and 16 were at baseline levels.
Uric Acid: During the INCIVEK combination treatment period, 73% of subjects had elevated uric acid levels compared to 29% for those treated with peginterferon alfa and ribavirin alone. Shifts to greater than or equal to 12.1 mg/dL from baseline in uric acid levels were also more frequent among subjects treated with INCIVEK (7%) compared to peginterferon alfa and ribavirin (1%). Less than 1% of subjects had clinical events of gout/gouty arthritis; none were serious and none resulted in treatment discontinuation.
7 DRUG INTERACTIONS
7.1Potential for INCIVEK to Affect Other Drugs
INCIVEK is an inhibitor of CYP3A. Co-administration of INCIVEK with drugs that are primarily metabolized by CYP3A may result in increased plasma concentrations of such drugs, which could increase or prolong their therapeutic effect and adverse reactions (see Table 5). INCIVEK is also an inhibitor of P-gp. Co-administration of INCIVEK with drugs that are substrates for P-gp transport may result in increased plasma concentrations of such drugs, which could increase or prolong their therapeutic effect and adverse reactions (see Table 5). If dose adjustments of concomitant medications are made during INCIVEK treatment, they should be re-adjusted after administration of INCIVEK is completed.
7.2Potential for Other Drugs to Affect INCIVEK
INCIVEK is a substrate of CYP3A and P-gp; therefore, drugs that induce CYP3A and/or P-gp may decrease INCIVEK plasma concentrations and reduce the therapeutic effect of INCIVEK. Co-administration of INCIVEK with drugs that inhibit CYP3A and/or P-gp may increase INCIVEK plasma concentrations.
7.3Established and Other Potentially Significant Drug Interactions
Table 5 provides effect of concentration of INCIVEK or concomitant drug with INCIVEK. These recommendations are based on either drug interaction studies (indicated with *) or predicted interactions due to the expected magnitude of interaction and potential for serious adverse events or loss of efficacy.
Table 5: Established and Other Potentially Significant Drug Interactions: Alterations in Dose or Regimen May Be Recommended Based on Drug Interaction Studies or Predicted
