A Hepatitis C Virus-Associated Cirrhotic Patient Developing Interstitial Pneumonia during the Course of Antiviral Therapy with Ombitasvir/Paritaprevir/Ritonavir

Oral direct-acting antivirals (DAAs) are the main therapy for hepatitis C virus (HCV)-associated liver disease in Japan. Daclatasvir/asunaprevir is the first agent and sofosbuvir/ledipasvir is the secondary agent for HCV genotype 1b. More recently, ombitasvir/paritaprevir/ritonavir is also recommended as a potent therapy for HCV genotype 1b. Among the adverse events associated with these oral DAAs, interstitial pneumonia is one of the most severe ones. Regarding treatment with daclatasvir plus asunaprevir or sofosbuvir plus ledipasvir, a few cases have already been reported in a postmarketing surveillance. Recently, we have encountered a HCV-associated genotype 1b cirrhosis patient who developed interstitial pneumonia during treatment with ombitasvir/paritaprevir/ritonavir and who recovered after drug discontinuation without corticosteroid therapy. Interstitial pneumonia was confirmed by chest x-ray and chest computed tomography. The serum KL-6 level was elevated to 1,180 U/mL. The total duration of the drug administration was 7 weeks, and she achieved SVR24. This is the first detailed report in the literature on the development of interstitial pneumonia during treatment with ombitasvir/paritaprevir/ritonavir. When dry cough appeared in the treatment with DAAs, chest computed tomography and the evaluation of serum KL-6 level were recommended.