Cost-effectiveness of tenofovir disoproxil fumarate prophylaxis for perinatal hepatitis B virus prevention in Ethiopia: a decision analytical modeling

Abstract

Background: Perinatal transmission of hepatitis B virus (HBV) remains a significant public health issue. To complement vaccination, tenofovir disoproxil fumarate (TDF) prophylaxis is recommended for HBV-infected pregnant women. We aimed to identify a cost-effective strategy for using TDF to prevent perinatal HBV transmission in Ethiopia.

Methods: A decision tree combined with a Markov model was used to determine the cost-effectiveness of different strategies for preventing perinatal transmission of HBV in a cohort of 10,000 hepatitis B surface antigen (HBsAg)-positive pregnant women. The existing vaccination strategy (Strategy 1) was compared with three alternative strategies that added TDF prophylaxis to the existing strategy. Strategy 2 (TDF prophylaxis following HBV viral load testing), Strategy 3 (TDF prophylaxis following hepatitis B envelope antigen (HBeAg) testing), and Strategy 4 (TDF prophylaxis for all HBsAg-positive). Costs were measured from the healthcare sector perspective. Effects were measured as HBV infection averted and disability adjusted life years (DALYs) averted. Model input parameters were obtained from the literature review and local data. Cost-effectiveness was determined by the incremental cost-effectiveness ratio (ICER), with thresholds set at 0.34, 1, and 3 times the GDP per capita of Ethiopia. A sensitivity analysis was conducted to test the robustness of the results.

Results: Among the alternatives, Strategy 4 is the most cost-effective strategy, with an ICER of 220.3 US$ per DALY averted. Strategy 4 would prevent 267 perinatal HBV infections and averted 1048 DALYs per 10,000 HBsAg-positive pregnant women. These results were robust to a range of parameters and showed a 97% probability of being cost-effective at one times the GDP per capita of Ethiopia. The next optimal strategy is Strategy 2, compared with the next best alternative, with an ICER of 1175.52 US$ per DALY averted. Strategy 3 was dominated by the available strategies.

Conclusion: Providing TDF prophylaxis for all HBsAg-positive pregnant women starting at 28 weeks of pregnancy has the potential to be a cost-effective strategy in Ethiopia. Introduction of TDF prophylaxis for all HBsAg-positive pregnant women is highly recommended, along with efforts to improve vaccination coverage.

Keywords: Cost-effectiveness; Ethiopia; Hepatitis B; MTCT; Perinatal; Tenofovir.

Fig. 1

Schematic design of the decision tree model for cost-effectiveness analysis of HBV strategies. HB Hepatitis B; VL: Viral load, HBsAg; hepatitis B surface antigen; TDF, tenofovir disoproxil fumarate. The square box shows the decision node; M shows where the Markov model continues; the circle is a chance node, and the triangle shows the outcome

Fig. 2

Markov diagram for cost-effectiveness analysis of HBV strategies. This diagram illustrates the disease progression of HBV infection. The arrow shows disease progression between Markov states. HCC: Hepatocellular Carcinoma

Fig. 3

Cost effectiveness plane of all HBV PMTCT strategies. NB: Smaller values of DALYs are the preferred outcome. To show in cost effectiveness plane in usual way (1- DALYs) was used to represent incremental DALYs averted

Fig. 4

Tornado diagram presenting one-way sensitivity analyses of HBV PMTCT strategies in Ethiopia 2024. VL: Viral load, Prev: prevalence, RR: relative risk, TDF: tenofovir disoproxil fumarate, Tp: transition probability, (A) Tornado diagram of Strategy 4 vs. status quo. (B) Tornado diagram of Strategy 2 vs. Strategy 4

Fig. 5

Incremental cost-effectiveness scatter plots of 1000 iterations for Strategy 4 compared with the status quo in Ethiopia, 2024

Fig. 6

Cost-effectiveness acceptability curve of HBV PMTCT strategies in Ethiopia 2024. Cost-effectiveness acceptability curve of Strategy 4 compared with the status quo. (A) The dashed line indicates WTP at 0.34 times (383), one time (1129), and three times (3387) GDP per capita of Ethiopia. (B) Cost-effectiveness acceptability curve of Strategy 2 compared with Strategy 4. The dashed line indicates three times (3387) the GDP per capita of Ethiopia