Low Uptake of Direct-Acting Antivirals for Hepatitis C in U.S. Clinics -- Race and Income Key Factors

Only 6% of 9500 hepatitis C (HCV)-infected people in a U.S. clinic cohort started direct-acting antivirals (DAAs) in 2014 and 2015, according to analysis of an observational cohort. Black race, Medicaid use and low income reduced odds of starting DAAs.

Second-generation DAAs became available for HCV infection at the end of 2013. Their high cost and restrictions on prescription raised concerns about how widely they would be used. Researchers working with the Chronic Hepatitis Cohort Study (CHeCS) conducted this study to assess DAA uptake and to identify factors affecting uptake.

CHeCS gathers data from electronic medical records on adult hepatitis patients in four large health care systems in Pennsylvania, Michigan, Oregon and Hawaii. This analysis involved HCV-infected adults with one or more clinic visits in 2013, excluding patients who died or had a sustained virologic response (SVR) before 2014. The researchers defined DAA uptake as the proportion of patients who were infected with HCV by December 31, 2013, prescribed a DAA during 2014 and started the DAA regimen by August 31, 2015.

Of the 9508 study participants, 59% were men, 65% white, 23% black and 67% between 50 and 70 years old. Among people with known insurance status, 46% had private insurance, 32% Medicare and 13% Medicaid. Three-quarters had HCV genotype 1, 14% had a FIB-4 fibrosis score between 3.25 and 5.88 and 14% had FIB-4 above 5.88. Small proportions were coinfected with HIV (3%) or hepatitis B (HBV) (1%).

From January 2014 through August 2015, 544 of 9508 cohort members (5.7%) started a DAA regimen. Multivariate analysis identified five factors independently associated with higher odds of starting DAAs, at the following adjusted odds ratios (aOR):

  • Higher annual income (>$50,000 versus <$30,000): aOR 2.3
  • Higher FIB-4 score (versus <2): FIB-4 >5.88, aOR 2.1; FIB-4 3.25-5.88, aOR 2.0; FIB-4 2.0-3.25, aOR 1.4
  • Genotype 2 versus 1: aOR 2.2
  • Pre-2014 HCV treatment failure versus treatment-naive: aOR 2.0
  • HIV coinfection: aOR 1.8

Three factors independently predicted a lower chance of starting DAAs:

  • Black versus white race: aOR 0.7
  • Medicaid versus private insurance: aOR 0.5
  • Care at a study site versus tertiary hepatology referral: aOR 0.3

Factors not affecting DAA uptake in this analysis included sex, age, HBV coinfection, Charlson comorbidity score, liver transplant history and duration of follow-up in CHeCS.

Approximately two-thirds of cohort members started DAAs within one month of their DAA prescription, while fewer than 20% started within one to three months or more than three months after their prescription. Gastroenterologist/hepatologists wrote 87% of DAA prescriptions, infectious disease specialists 12% and primary care clinicians less than 1%.

The CHeCS team noted that their analysis is limited to DAAs prescribed in 2014 and that uptake may have improved as new agents gained approval and system barriers declined. They stressed that their analysis could not account for potentially relevant uptake factors such as drug or alcohol use, mental health and limited DAA availability at the time of the analysis. The researchers plan to survey a subset of study participants to gain a better understanding of patient-related uptake factors.

Mark Mascolini writes about HIV and hepatitis virus infection.