Evaluating the approach
To determine whether a lower-cost rapid test could be cost effective, the researchers created a microsimulation model of the natural history of HCV to compare potential outcomes from either core antigen rapid diagnostic testing with a base case sensitivity for HCV viremia of 80% with lab-based RNA confirmation for negative results or the current standard of care with lab-based RNA confirmation only.
The model incorporated METAVIR stage F0-F4, decompensated cirrhosis, hepatocellular carcinoma, and liver-related death. The investigators determined the baseline characteristics of HCV patients in each country based on different distributions of sex, HCV genotype, and METAVIR fibrosis stage.
They simulated outcomes for 10,000 adults in the Republic of Georgia, with an HCV prevalence of 5.4%, and Malaysia, with an HCV prevalence of 1.5%.
The model considers costs from a health care payer’s perspective, and the investigations performed deterministic and probabilistic sensitivity analyses to evaluate how the cost-effectiveness of testing pathways might change when various factors were plugged into the model.
As noted before, the investigators determined that the core antigen rapid test algorithm would improve diagnosis rates in Georgia from 78.8% to 95.4% and in Malaysia from 57.9% to 91.2%.
The use of the rapid test would also increase quality-adjusted life-years in Georgia by 207 per 10,000 and in Malaysia by 146 per 10,000.
Cost savings, primarily from averting the costs of care for patients with HCV, begin within the first year of the model. Over 50 years, the lifetime horizon cost savings in Georgia would be $232,000 per 10,000 people, and the corresponding savings in Malaysia would be $504,000 per 10,000 people.
Even when allowing for variations in parameters, the core antigen rapid diagnostic test approach remained the preferred model, the investigators reported.
The study was supported by the global health agency Unitaid. The researchers, Dr. Miller, and Dr. Hoerger reported no conflicts of interest relevant to the study.