Study of DAA for HCV Finds High Adherence, Lower Costs

Shaoman Yin, PhD, MSPH

A large US based population study of chronic hepatitis C (CHC) treatment with direct-acting antivirals (DAAs) finds high levels of adherence, reduction in both drug and medical costs from when the antivirals were introduced, and comparable effectiveness to that attained in clinical trials.

Shaoman Yin, PhD, MSPH, and colleagues at the Division of Viral Hepatitis, National Center for HIV/AIDS, Viral Hepatitis, STD, and TB Prevention, Centers for Disease Control and Prevention (CDC), Atlanta, GA conducted the study to add to the limited data available on real-world use of the DAAs in a nationwide population, and to examine the effects of some patient and payer differences which could not be assessed in clinical trials.

"For example, treatment adherence in routine care is complex and influenced by many factors, including characteristics and preferences of patients and providers, payer policies, and other health system factors," Yin and colleagues pointed out.

The study cohort comprised "well-insured" patients who had initiated a sofosbuvir (Sovaldi)-based regimen for CHC between November 2013 and July 2015. To be eligible for the analysis, they were to have had insurance coverage for at least 6 months before and after initiating treatment, to encompass the longest treatment regimen found in the population—24 weeks. Patients with a diagnosis of hepatitis B were excluded from the analysis.

The investigators accessed data from the MarketScan Commercial Claims and Encounters (CCAE) and Medicare Supplemental databases from January 2012 through December 2015, comprising claims for approximately 91 million persons. Records were identified for 1761 patients treated with sofosbuvir (SOF) + simeprevir (SIM) ± ribavirin (RBV); 1314 with SOF + pegylated interferon alpha-2a or 2b (PEG); 1994 with SOF + RBV; and 5739 with ledipasvir/sofosbuvir (Harvoni, LED/SOF) ± RBV.

Treatment adherence was derived from prescription claims data, with those having more than 80% of the treatment days covered considered adherent, and those with less than 80% classified as nonadherent to treatment. Drug costs were the summation of the drug cost, dispensing fees, and sales tax. Medical costs included all-cause inpatient and outpatient costs, excluding drugs. Treatment effectiveness was measured as the percentage of patients attaining sustained virologic response 12 weeks after treatment (SVR12).

Yin and colleagues estimated adherence rates at 80.5%, 81.5%, 85.7%, and 91.4% for SOF+SIM ± RBV, SOF+PEG+RBV, SOF+RBV, and LED/SOF ± RBV, respectively. Payer type, health plan, and treatment option with RBV were predictors of adherence with the SOF+SIM ± RBV regimen; while sex and age group were adherence predictors in SOF+RBV, and LED/SOF± RBV, respectively. The investigators were unable to identify reasons for this variability.

Overall SVR12 was 92.6% in 203 patients with available HCV RNA results; 100% with SOF+SIM ± RBV; 83.3% with SOF+PEG+RBV; 90.6% with SOF+RBV; and 93% with LED/SOF ± RBV.

"We were pleased to see that the real-world treatment adherence and SVR of sofosbuvir-based regimens for chronic hepatitis C treatment found in this large population-based study were comparable to that from clinical trials and cohort studies," Yin commented to MD Magazine^®.

Drug costs were found to have decreased by 18.9% from initial levels. The investigators attributed this to competing treatment options becoming available and large volume purchasers negotiating better prices.

Medical costs were also found to have decreased during the study period. Overall, the mean ± standard deviation of the 1-year medical costs decreased from $4,730±22,149 (median $1,051) to $4,296±20,296 (median $881), with mean reduced 9.2%. Yin and colleagues suggested that the reduction in medical costs reflects the positive effects of DAA treatment on the healthcare system, and they anticipated that expanded DAA access will reduce socioeconomic burdens of HCV.

"The combination of less costly regimens that have become available since 2015 and high patient adherence rates found in this study indicates encouraging opportunities for more chronic hepatitis C patients to achieve cure," Yin said. "However, as this analysis only covers the well-insured population, studies are needed to understand access and adherence in less insured/uninsured populations."

The study, “Sofosbuvir-Based Regimens for Chronic Hepatitis C in a Well-Insured U.S. Population: Patient Characteristics, Treatment Adherence, Effectiveness, and Health Care Costs, 2013-2015,” was published in the Journal of Managed Care & Specialty Pharmacy.