Endobest: Does saliva testing improve endometriosis management?

This Thursday, July 3, several young women presented themselves at the Clinical Research Center of the Nice University Hospital (Archet 1 hospital).

All of them have suffered for many years from symptoms suggestive of endometriosis, but imaging tests carried out at an expert center have not revealed any lesions.

They are participating in Endobest, a clinical trial that allows them to benefit from the Endotest saliva test, developed by the company Ziwig.

Since February 11 and for three years, this non-invasive test – presented as a revolution for the diagnosis of endometriosis – has been reimbursed to certain patients as part of the innovation package, a system allowing for the testing of a new product in real conditions, while being provisionally financed by health insurance.

In total, 25,000 adult women will be able to benefit from it, including the first 2,500 as part of the Endobest study, which aims to evaluate its clinical impact.

The Nice University Hospital, selected to participate in this research, entrusted the coordination to Dr. Pierre-Alexis Gauci, obstetrician-gynecologist.

He receives in consultation the candidates for the study, conducted simultaneously in a hundred establishments in France. Interview.

What is Endotest and who is it for?

It is a non-invasive test based on saliva analysis, developed for patients with typical symptoms of endometriosis, but for whom imaging has not been able to confirm the diagnosis, and for whom treatments are not (or insufficiently) effective.

What is the Endobest study?

This is a national clinical trial aimed at evaluating this test in very specific situations: adult patients, presenting suggestive symptoms, with normal imaging, performed in an expert center, and failure of hormone treatment. In other words, patients often "at the end of the process." One hundred establishments are involved. We preselect based on medical records and also welcome external participants.

Why a large-scale trial if the test performance is already known?

Previous studies have shown a diagnostic performance of around 95% in targeted situations. But before authorizing expanded reimbursement, the Health Insurance wants to verify whether the test actually improves care: Does it reduce unnecessary exploratory surgeries? Does it direct patients to other tests in the event of a negative result? Does it improve quality of life and psychological health?

What are the consequences depending on the test result?

A positive test confirms an expected diagnosis. The women concerned will finally put a name to their pain, which should improve adherence to treatments (hormonal, analgesic, physiotherapy, etc.) and allow, if necessary, to discuss fertility preservation. If the test result is negative, this should already have the virtue of reducing the anxiety linked to waiting for a diagnosis; endometriosis can be excluded and other causes explored: irritable bowel syndrome, interstitial cystitis, rare digestive or urinary pathologies, etc. In all cases, this test aims to allow a more appropriate care pathway, centered on the patient's complaint and not solely on the search for endometriosis.

Can the test be used more widely?

No, or at least not as things stand. This is not a screening tool for the general public, but a test intended for women already being treated for suspected endometriosis. Research is underway for other indications (chronic pain, infertility, post-surgery follow-up), but reimbursement will remain limited to validated use.

How many patients will the Nice University Hospital be able to include?

Recruitment is "competitive": the first centers to be included will fill the quotas. We already have dozens of patients registered. Demand is high, and the next session is scheduled for next Tuesday (1).

When are the results expected?

Inclusion is expected to last a little over a year, but at the current rate, the 2,500 patients could be recruited by the end of 2025. The final analysis will then take several months.

1. For all information, health professionals, like the public, can contact the endometriosis pathway coordination / RCP Nice Endocentre, tel.: 06.28.18.35.10. or by e-mail: [email protected]