People whose hepatitis C virus (HCV) treatment regimens include ribavirin often wind up with concentrations of the drug that are too high or too low, the National AIDS Treatment Advocacy Project (NATAP) reports. Presenting their findings at the 17th International Workshop on Clinical Pharmacology of HIV and Hepatitis Therapy in Washington, DC, researchers retrospectively studied 100 people in the Netherlands receiving ribavirin as a part of treatment for hep C.
The researchers analyzed ribavirin levels at week eight of treatment.
Twenty-nine percent of the individuals had ribavirin levels below and 26 percent had levels above the target range. Concentrations of the drug did not vary based on gender, weight or regimen of direct-acting antivirals (DAAs). Twenty-one percent of the individuals developed anemia, a potential side effect of ribavirin.
The researchers concluded that those with lower kidney function, specifically an estimated glomerular filtration rate (eGFR) below 50 milliliters per minute and possibly those with an eGFR of 50 to 70 mL/min, would benefit from starting hep C treatment with a lower ribavirin dose. They stated that “therapeutic drug monitoring could be beneficial to improve ribavirin concentrations during DAA treatment,” particularly among those with moderately compromised kidney function, with the ultimate goal of curing the virus while avoiding toxicity from treatment.
To read the NATAP report, click here.