Analytical approach:
Two health state transition Markov models were used (one each for treatment-naïve and treatment-experienced patients) to synthesise evidence from published studies, epidemiological data and key clinical trials (Steigbigel RT et al. 2008 & 2010, Lederberger B et al. 2010, Martinez E et al. 2010 & Eron J et al. 2010 see Other Publications of Related Interest). The base case analysis time horizon was 30 years (UK) and 50 years/lifetime (Spain, Switzerland, Hungary, Portugal, Sweden and Australia). The authors’ stated the study perspective was that of the respective health system in each country. Country-specific data was used for data inputs when available.
Effectiveness data:
Clinical outcomes included indicators of virologic response (CD4 counts), disease progression, primary and recurrent opportunistic infections. Results of randomised trials of raltegravir plus OBT versus OBT alone were used to derive data inputs to the model (Steigbigel RT et al. 2010, Lederberger B et al. 2010, Druyts E et al. 2009, see Other Publications of Related Interest). Risk of opportunistic infections and AIDS-related complications were based on those reported in the Multicenter AIDS Cohort Study. Assumptions were made on the duration of immunologic failure rates.
Monetary benefit and utility valuations:
Utility estimates were derived from a previous published HIV cost-effectiveness study (Simpson KN et al. 2004, see Other Publications of Related Interest).
Measure of benefit:
Undiscounted life expectancy and quality-adjusted life-years (QALYs) discounted annually according to national recommended discount rates (%).
Cost data:
Direct medical costs included antiretroviral pharmaceuticals, drug administration and monitoring, opportunistic infection prophylaxis treatment, all hospital costs, laboratory tests, clinical examinations, treatment of adverse events and other service costs. Resource use quantities were determined from analyses of patient-level data with patients with HIV at the British Columbia Center of Excellence for HIV/AIDS and published literature. The unit costs were country-specific and derived from the respective country sources. Prices were presented in 2007 Euros (€) and 2010 exchange rates were applied.
Analysis of uncertainty:
The model input parameters were examined with one-way sensitivity analyses. Parameters tested included time horizon, discount rate, utilities, incidence of opportunistic infections, drug price, treatment duration and treatment failure rates.