Antiviral therapy improves hepatic outcomes in hepatitis C virus (HCV)-infected cancer patients. However, such patients are not treated simultaneously with antivirals and chemotherapy owing to overlapping toxicities with previous standard of care treatment of pegylated interferon and ribavirin.
We aimed to examine the safety and clinically significant drug-drug interactions observed in patients who received simultaneous treatment with direct-acting antivirals (DAAs) and chemotherapy.
Safety was determined by the presence of adverse events which were graded according to the division of AIDS Table (version 2.0). Adverse events were monitored throughout antiviral treatment and up to 3 months after its completion. Drug-drug interactions were assessed using current online databases. Sustained virological response (SVR) was defined as absence of serum HCV RNA 12 weeks after end of DAA treatment. Cirrhosis was diagnosed via imaging, biopsy or with the use of noninvasive fibrosis markers.
Twenty-one patients received concomitant treatment with DAAs and chemotherapy between 1/2013 and 9/2016. Concomitant treatment was started either for virologic (14; 67%) or oncologic (7; 33%) reasons. DAAs used were sofosbuvir, ledipasvir, simeprevir, daclatasvir +/− ribavirin. The adverse events observed were mainly constitutional (12; 57%), haematological and gastrointestinal (7; 33% each). Physicians changed the DAA regimens in two patients (10%) in anticipation of drug-drug interactions with daclatasvir and tacrolimus. The overall SVR rate was 95% (20/21).