Dermatologic adverse events of protease inhibitor-based combination therapy in patients with chronic hepatitis C

Combination therapy with pegylated interferon, ribavirin and a first-generation NS3/4A protease inhibitor, telaprevir or boceprevir, is the new strategy for treatment of genotype 1 chronic hepatitis C virus infection. This combination improves therapeutic efficacy but it also increases the risk of adverse events.

The aim of the study was to analyze frequency and severity of dermatological adverse events during protease inhibitor-based therapy and to evaluate the risk factors for their development.

This is a retrospective study of 109 patients with genotype 1 chronic hepatitis C treated with boceprevir (n=33) or telaprevir (n=76) based triple therapy. A logistic regression for relationship between clinical, demographic and laboratory factors and cutaneous adverse events was performed.

Dermatological adverse events (skin rash, pruritus, anorectal paresthesia) occurred in both treatments (boceprevir and telaprevir) with similar frequency: 28% in telaprevir and 21% in boceprevir. In patients treated with telaprevir, men were more predisposed to develop skin rashes compared to women (OR 4,1 p=0,014) and age above 45 years was associated with occurrence of pruritus in men (OR 8,16 p=0,014). Being a female, coexistence of autoimmune thyroiditis and advanced liver fibrosis were independent factors predisposing to development of anorectal paresthesia (OR 4,13 p=0,041, OR 4,25 p=0,029, OR 4,54 p=0,018 respectively) in this group. In patients treated with boceprevir, coexistence of autoimmune thyroiditis predisposed to skin rashes (OR 10,22 p=0,017) and being a female predisposed to pruritus (OR11,2 p=0,033). The adverse events occurred after a mean time of 8,6 (range 1-24) weeks after initiation of therapy.

In patients with chronic hepatitis C who received the triple therapy, the anorectal paresthesias were observed only in patients treated with telaprevir. The predisposing factors for this adverse event were: female gender and advanced liver fibrosis. The risk factors for other dermatological adverse were: 1) being a male over 45 years, for skin rashes and pruritus (for telaprevir), 2) coexistence of autoimmune thyroiditis for skin rashes (for boceprevir), 3) being a female, for pruritus (for boceprevir).