(1129) Patterns, Trends and Predictors of Direct Acting Antivirals (DAA) Treatment Initiation Among Medicare Beneficiaries with Hepatitis C

Objectives: Although highly effective, Direct Acting Antivirals (DAAs) used to treat hepatitis C viral (HCV) infection are expensive and carry a significant cost to the US health care system. Medicare is a large provider and contributor to the increasing healthcare expense related to HCV. Restrictions such as high cost-sharing, advanced fibrosis, and prescribing by specialists are hypothesized to differ among vulnerable populations, including racial/ethnic minorities. Prior studies examining racial disparities in HCV medication use have found mixed results. However, these studies are not generalizable to Medicare beneficiaries and have not been updated to reflect more recent patterns of prescribing and treatments for DAAs. This study was conducted to 1) determine the incidence and trends of treatment initiation with different DAAs, and 2) examine the association of patient characteristics including race/ethnicity with DAA treatment initiation in Medicare beneficiaries with HCV from 2014 to 2019.

Methods: This retrospective cohort study uses Medicare beneficiaries diagnosed with hepatitis C between 2014 and 2019 as the study population. Medicare claims from 2013 through 2019 for inpatient, skilled nursing facility, outpatient, and physician services will be used to identify HCV patients. Patients will be included in the study if they newly sought HCV care between January 1, 2014 and December 31, 2019, incorporating a one-year washout period. Patients will be required to have continuous enrollment in Medicare parts A, B, and D throughout the period of observation. The index date for each beneficiary is defined as the date of the first HCV claim following the one-year washout period, excluding patients with prior DAA treatment. Use of DAAs, the outcome variable, will be identified using national drug codes (NDCs) of the one of the following DAAs from the 2014-2019 Medicare Prescription Drug Event Files: elbasvir/grazoprevir, glecaprevir/pibrentasvir, ledipasvir/sofosbuvir, ombitasvir/paritaprevir/ritonavir and dasabuvir, sofosbuvir (with/without peginterferon or simeprevir or daclastasvir), sofosbuvir/velpatasvir, or sofosbuvir/velpatasvir/voxileprevir. The primary predictor variable in our models is a patient’s race/ethnicity. We will compare treatment use among the following race/ethnicity categories: white, Black, Hispanic, Asian, and others. Covariates include patient age, sex and geography, smoking, alcohol use, HIV status, hepatitis B infection and diabetes, hepatic fibrosis, hepatocellular carcinoma, and history of liver transplantation, hypertension, renal disease, diabetes, and number of Elixhauser conditions and the year of treatment initiation. These variables will be identified through Medicare Master Beneficiary Summary Files (MBSF) as well as inpatient and outpatient claims. Descriptive statistics will be used to describe rates of DAA initiation for different DAA regimens. In order to test hypotheses, multivariable regression analysis will be performed. These models will compare rates of DAA initiation by race adjusting for other covariates.

Results: Data have been accessed for the study. Data analysis and generating results for this study are in progress.

Conclusions: The results of this study are relevant to two Healthy People 2030 objectives which have called for an increase in the proportion of people who have cleared HCV infection and a reduction in mortality from HCV. In our study, we will be able to update the current status of treatment, including what proportion of patients have been and what proportion to be treated with HCV treatment to achieve Healthy People 2030 objectives. To our knowledge, this study represents the largest sample of Medicare beneficiaries to examine treatment patterns and potential disparities in treatment among Medicare beneficiaries with HCV. These results will identify opportunities for improved HCV treatment uptake in racial/ethnic minority populations which can help reduce healthcare expenditures and enhance overall public health.