A model incorporating IL28B genotype, fibrosis stage, viral load and rapid virologic response was predictive of benefit from dual therapy among patients with chronic hepatitis C in a recent study.
In a retrospective analysis, researchers evaluated 1,045 treatment-naïve Caucasian patients with chronic HCV genotype 1 treated with pegylated interferon and ribavirin according to two models: The first incorporated only baseline variables associated with sustained virologic response at 24 weeks post-treatment (SVR), with the second model also included rapid virologic response at 4 weeks of therapy (RVR).
SVR occurred in 39.6% of participants, while RVR occurred in 24.4% of cases. Patients who achieved RVR also achieved SVR in 80% of cases, while SVR without RVR occurred in 26.6% of participants.
During analysis using the baseline predictor-only model, factors associated with SVR via multivariate analysis included IL28B CC genotype (OR=5.082, 3.637-7.101), viral load below 400,000 IU/mL (OR=2.907, 2.111-4.004), fibrosis of stage 2 or lower (OR=1.631, 1.122-2.372) and diabetes (OR=0.528, 0.286-0.972). Analysis according to the second strategy also indicated that RVR was significantly associated with SVR (OR=6.273, 4.274-9.208), along with CC genotype (OR=3.306, 2.301-4.751), low viral load (OR=2.175, 1.542-3.07) and fibrosis stage 0-2 (OR=1.506, 1.012-2.242), along with RVR (OR=6.273, 4.274-9.208) (95% CI for all).
According to the first model, SVR probability ranged from 42.4% to 83.3% based on which predictors are present in the patient, with 83.3% probability observed among participants with CC genotype, early-stage fibrosis and low viral loads. According to the second model, patients who achieved RVR had a 100% chance of also achieving SVR if both CC genotype and low viral load were present, regardless of fibrosis stage, and approximately 80% probability with one predictor. Using this model, 19.1% of patients at week 4 had an 80% chance of achieving SVR.
“Until peginterferon and ribavirin constitute the backbone [of] new, triple therapies, we have to consider that conventional dual therapies are still effective and less expensive than triple therapies,” researcher Angelo Andriulli, MD, chief of the gastroenterology division at Csa Sollievo Sofferenza Hospital in San Giovanni Rotondo, Italy, told Healio.com. “The crucial point is to select patients most suitable to benefit from conventional dual therapies. … While the evaluation of baseline features may help to select the subset of patients with a high likelihood of viral clearance after therapy, attainment of viral clearance by the initial month of therapy is the strongest predictor of response.”
Disclosure: The researchers report no relevant financial disclosures.