Noninvasive fetal RHD genotyping of RhD negative pregnant women for targeted anti-D therapy in Australia : a cost-effectiveness analysis

Objective: To undertake a cost-effectiveness analysis of noninvasive fetal RHD genotyping to target pregnant women for antenatal anti-D prophylaxis therapy. Method: A decision-analytic model was constructed to compare RHD testing and targeted anti-D prophylaxis, with current universal anti-D prophylaxis among pregnant women with RhD negative blood type. Model estimates were derived from national perinatal statistics, published literature, donor program records, and national cost sources. One-way sensitivity analyses addressed the uncertainty of variables on the main findings. Results: The unit cost for RHD genotyping was estimated at AU$45.48 (US$31.84). The “mean cost per healthy baby” was AU$7495 (US$5247) for universal prophylaxis and AU$7471 (US$5230) for targeted prophylaxis. The findings were sensitive to the unit costs of anti-D 625 IU (AU$59-AU$88) (US$41-US$62), the genetic test (AU$36-AU$55) (US$25-US$39), and packaging/transport costs of the samples for testing (AU$15-AU$40, US$11-US$28 per sample). With RHD genotyping, 13 938 women would avoid antenatal anti-D prophylaxis at a total cost savings to the National Blood Authority of AU$2.1 million (US$1.5 million) per year. To the health system, net cost savings of AU$159 701 (US$111 791) per year (0.05%) were predicted for total health care costs. Conclusions: Given the vulnerable supply of donor plasma and other health concerns, RHD genotyping is an economically sound option for Australia.