RESUMEN
BACKGROUND: 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. AIM: To examine the safety and clinically-significant drug-drug interactions observed in patients who received simultaneous treatment with direct-acting antivirals (DAAs) and chemotherapy. METHODS: 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 non-invasive fibrosis markers. RESULTS: Twenty-one patients received concomitant treatment with DAAs and chemotherapy between January 2013 and September 2016. Concomitant treatment was started either for virological (14; 67%) or oncologic (7; 33%) reasons. DAAs used were sofosbuvir, ledipasvir, simeprevir, daclatasvir ± ribavirin. The adverse events observed were mainly constitutional (12; 57%), hematological and gastrointestinal (7; 33% each). Physicians changed the DAA regimens in two patients (10%) in anticipation of drug-drug interactions with daclatasvir and dexamethasone. The overall SVR rate was 95% (20/21). CONCLUSIONS: Hepatitis C virus-targeted antiviral therapy can be used concomitantly with selected anti-neoplastic agents under close monitoring for drug-drug interactions. This therapeutic intervention may prevent delay in the administration of chemotherapy in HCV-infected cancer patients.