DAAs safely treat chronic kidney disease in HCV patients

Sofosbuvir-based direct-acting antiviral (DAA) therapy is safe and effective in patients with chronic kidney disease who are infected with hepatitis C virus (HCV), according to a new study.

HCV infection is common among patients with chronic kidney disease (CKD) and leads to accelerated progression to end-stage renal disease. Sofosbuvir is a potent DAA against HCV, however, a previous analysis of nationally collected data raised some concerns about a risk of acute kidney injury among more advanced kidney disease patients treated with the drug.

“We found no signal of kidney injury with DAAs in advanced kidney failure. The glomerular filtration rate (GFR) remains stable on therapy,” Meghan Sise, MD, an instructor in medicine at Massachusetts General Hospital and study co-author, told Medical Economics.

“In addition, these drugs are effective and may have a higher chance of a cure in patients with lower GFR. There was also an association between cure and GFR in the follow-up period, so when patients are cured of HCV infection, their kidney function could improve.”

The researchers published their results online September 7, 2017, in the Clinical Journal of the American Society of Nephrology.

Next: Study details

Sise and colleagues conducted a retrospective observational study of 98 patients with CKD, defined by estimated GFR less than 60 ml/min per 1.73 m², 30 mg albuminuria per 1 g creatinine or higher or 200 mg proteinuria per 1 g creatinine or higher. The patients, mean age 62 years, with stage 1 to stage 3 CKD and HCV infection received at least one dose of sofosbuvir. Antiviral regimens included either simeprevir or ledipasvir, with or without ribavirin, depending on the HCV genotype, presence of cirrhosis and prior treatment experience.

Overall, 81% of patients achieved sustained virologic response, which varied by regimen used and viral genotype. The study began in 2014 and Sise noted “now we have newer DAA agents and cure rates may be even higher.”

Treatment appeared to be more effective in patients with more advanced CKD. In patients with stage 3 CKD, HCV cure was associated with a 9.3 ml/min per 1.73 m² improvement in GFR during the 6-month post-treatment follow-up period. She suggested that the increased efficacy of DAA therapy in patients with lower GFR may be due to higher blood levels of sofosbuvir because of less efficient elimination by the kidney.

Adverse events were common (81%) - most commonly among patients taking ribavirin - but serious adverse events (17%) and treatment discontinuations (8%) were uncommon. There were no clear episodes of nephrotoxicity, she noted.

“The study included only 98 patients and there was no untreated control group, but the results certainly suggest if HCV-infected patients need to be treated they should be treated. For those with a GFR greater than 30, the treatment is safe,” said Sise.

The researchers plan to conduct a study of 2,000 patients to examine how DAA treatment and cure of HCV affects kidney function decline.

Sise said that primary care physicians should “look to identify patients with CKD with hopes to improve their kidney function. For those CKD patients with GFR greater than 30, you can feel comfortable with a sofosbuvir-based regimen, along with monitoring through guidelines.”