Rash

In controlled clinical trials, rash events (all grades) were reported in 56% of subjects who received INCIVEK combination treatment and in 34% of subjects who received peginterferon alfa and ribavirin. Rash most frequently began during the first 4 weeks, but could occur at any time during INCIVEK combination treatment. Improvement of rash occurs after INCIVEK dosing completion or discontinuation; however, rashes may take weeks for complete resolution.

Rash events led to discontinuation of INCIVEK alone in 6% of subjects and discontinuation of INCIVEK combination treatment in 1% of subjects.

For serious skin reactions and severe rash, see Warnings and Precautions (5.2 and 5.3).

Anemia

In controlled clinical trials, the overall incidence and severity of anemia increased with INCIVEK combination treatment compared to peginterferon alfa and ribavirin alone. The incidence of anemia adverse events was 36% with INCIVEK combination treatment compared to 17% with peginterferon alfa and ribavirin alone. A decrease in hemoglobin levels occurred during the first 4 weeks of treatment, with lowest values reached at the end of INCIVEK dosing. Hemoglobin values gradually returned to levels observed with peginterferon alfa and ribavirin after INCIVEK dosing was completed [see Warnings and Precautions (5.4)].

Anorectal Signs and Symptoms

In the controlled clinical trials, 29% of subjects treated with INCIVEK combination treatment experienced anorectal adverse events, compared to 7% of those treated with peginterferon alfa and ribavirin alone. The majority of these events (e.g., hemorrhoids, anorectal discomfort, anal pruritus, and rectal burning) were mild to moderate in severity; less than 1% led to treatment discontinuation and all resolved during or after completion of INCIVEK dosing.

Laboratory abnormalities