French-Backed Endometriosis Saliva Test Faces Scrutiny Over Effectiveness

In 2022, France launched an ambitious strategy to combat endometriosis, a chronic condition affecting 10% of women of reproductive age worldwide, characterized by the growth of uterine tissue outside the uterus. A key component of this initiative was the promotion of a new saliva-based test called Endotest, developed by the French start-up Ziwig. Marketed as a revolutionary diagnostic tool utilizing artificial intelligence and microRNA technology, the test aimed to simplify the diagnostic process, which currently relies on invasive surgery. Ziwig’s founders boasted that the Endotest could enable early detection of all endometriosis forms, even the most complex, promising a significant breakthrough in women's health.

Despite the high-profile support from French authorities, including statements from the former health minister and the current health minister who visited Ziwig's labs, questions about the test’s validity remain. The French government has invested approximately 21 million euros ($25 million) to subsidize the test, making it a notable component of national health spending. However, critical scientists and medical experts have raised concerns over the reliability of the data supporting Endotest’s effectiveness.

The main evidence presented by Ziwig comes from two scientific studies, one published in the Journal of Clinical Medicine in 2022 and another in NEJM Evidence in 2023. Experts like Professor Kevin McConway point out that these studies are preliminary and lack robust external validation. Some studies involved small and non-representative sample populations, such as 200 French women already suspected of having endometriosis. Consequently, many question whether the results can be generalized to the wider population.

The French National Authority for Health (HAS) has acknowledged that while the Endotest demonstrated 'validated diagnostic performance,' further research is needed to confirm its clinical utility. Currently, the test is only reimbursed after other imaging techniques fail, often as a last resort to avoid surgery—an indication that its role as an initial diagnostic tool is not yet established.

Critics argue that with only about 11 million euros invested in broader endometriosis research under France’s women’s health programs—about half the amount allocated to the Endotest—it is unclear whether the focus on this specific technology is justified. Other diagnostic avenues, such as improved ultrasound techniques, continue to be underfunded.

Ziwig’s leadership, including president Yahya El Mir, defends the test’s quality and claims that no other product globally matches its standards. The company is also seeking peer review for its clinical data, which has yet to be published in leading scientific journals.

Patient advocacy groups like Endomind support access to the test, but critics like former committee member Arounie Tavenet argue that the current focus on rapid approval and reimbursement may divert from more effective research and diagnostic strategies that could benefit patients in the long term.

This ongoing debate highlights the complexities of introducing innovative diagnostics in healthcare, emphasizing the need for thorough validation before widespread adoption. Source: https://medicalxpress.com/news/2025-09-endometriosis-french-scrutiny.html