SD Biosensor: Dual test for HIV and syphilis
Syphilis testing rates in pregnant women lag far behind those for HIV, despite the serious risks to mothers and babies.
From 2021 to 2025, we supported SD Biosensor with a volume guarantee to reduce the price of its HIV/syphilis rapid test, enabling more countries to protect mothers and babies with dual testing.
The challenge
Public health
Syphilis is one of several sexually transmitted infections that can be passed from a pregnant woman to her baby during pregnancy and childbirth. Pregnant women with untreated syphilis are 52% more likely to suffer adverse birth outcomes such as stillbirths, low birth weight and premature delivery.
The World Health Organization recommends that all pregnant women are tested for HIV and syphilis during their first antenatal care visit and has set a target to test at least 95% of the pregnant woman who attend. According to the latest data at the time of the agreement launch in 2021, despite between 70% and 100% of pregnant women being screened for HIV in low- and middle-income countries, only 40% to 60% were screened for syphilis.
Market situation
SD Biosensor developed a dual rapid diagnostic test (RDT) that enables simultaneous diagnosis of HIV and syphilis. The dual test offers an opportunity to integrate syphilis testing with donor-funded HIV testing programmes, which have high testing rates built on well-established guidelines and processes.
By mid-2021, country introductions of the dual test had been slow, primarily due to the price difference between the single HIV test and the dual test. Procurers had indicated that if the price for the test was closer to the price of single HIV tests, it would enable them to significantly increase procurement.
Impact
By the end of the agreement:
770k
pregnant women with syphilis treated
162k
stillbirths averted
$13.6m
saved for procurers
The product
The dual test is a point-of-care rapid diagnostic test that simultaneously detects antibodies to both Treponemal pallidum (TP, the cause of syphilis infection) and HIV in under 20 minutes from a single finger-prick blood sample.
The dual test means syphilis testing can be integrated into HIV testing programmes in antenatal care settings, closing the testing gap between HIV and syphilis.
The partnership
MedAccess provided a volume guarantee to SD Biosensor for the dual test.
SD Biosensor agreed to reduce the price of its dual test to below $1 for public purchasers in over 100 low- and middle-income countries. SD Biosensor continued to produce and supply the dual test, increasing availability and access to the product in low-and-middle-income countries.
CHAI helped to facilitate the volume guarantee agreement and continues to support country adoption of the dual test.
Impact
Our guarantee enabled SD Biosensor to offer the lowest price among all WHO pre-qualified HIV-syphilis dual test suppliers, encouraging more competitive pricing across the market. SD Biosensor’s market entry made the company the third supplier of dual tests in the market, which also contributes to increased supply security.
Bringing the price of the dual test closer to that of single HIV rapid diagnostic tests made replacing single tests with the dual test a more attractive proposition. By building on existing programmes and systems, more women were tested for syphilis who otherwise might have just been tested for HIV.
By the end of the agreement, we estimate that the partnership contributed to:
- more than 31 million pregnant women accessing dual HIV/syphilis tests,
- at least 770,000 pregnant women with syphilis being treated,
- at least 162,000 stillbirths being avoided,
- direct savings of over $13.6 million for procurers, over the volume guarantee period,
- 60+ countries introducing dual HIV/syphilis tests for the first time.
How we calculated the impact of this agreement
Lives changed
Estimates for additional women receiving access to syphilis testing were based on 2020 antenatal testing coverage for syphilis in African countries. Downstream patient outcomes were estimated based on 2020 seroprevalence and treatment rates in African countries, and a meta-analysis of risk for adverse outcomes of pregnancy by Gomez et. al.
Money saved
Impact was based on comparing the negotiated price to the expected weighted average market price of HIV-syphilis dual tests, including expected distributor mark-up where relevant.
Markets shaped
We work with partners, including donors, procurers and ministries of health, to track changes in health markets where our investments are supporting access to products. We monitor for changes to policy, procurement practices and supplier movement, all of which affect markets and contribute to the long-term sustainability of impact.
