An innovative cell therapy developed from the patient’s own cells has been shown to be safe and potentially effective in women with moderate to severe Asherman syndrome, a rare uterine condition associated with infertility and recurrent pregnancy loss, for which therapeutic options are limited.

The study, led by the company Endorenew and the Carlos Simón Foundation–INCLIVA and published in Nature Communications, presents the results of a phase 1/2 clinical trial conducted in women who had not responded to conventional surgical treatments. The Vall d’Hebron Research Institute (VHIR) provided the clinical framework for the study, which was coordinated at the centre by Dr. Julio Herrero, head of the Assisted Reproduction Unit at Vall d’Hebron University Hospital and researcher in the Maternal and Fetal Medicine research group at VHIR.

A clinical trial in patients with no effective alternatives

The trial included 20 women with moderate or severe Asherman syndrome, all of whom had a history of unsuccessful intrauterine surgery. The intervention consisted of the intra-arterial administration of an autologous cell therapy obtained from the patients’ own bone marrow cells.

Endometrial improvement and encouraging reproductive outcomes

The study results showed a significant improvement in endometrial structure and function, assessed using imaging techniques such as ultrasound, hysteroscopy and digital histology, as well as advanced transcriptomic analyses.

In addition, the therapy was well tolerated, with no serious treatment-related adverse events reported during clinical follow-up, which included pregnancy and childbirth. As a relevant clinical outcome, six patients achieved ongoing pregnancies, resulting in births without major complications and healthy newborns.

A hopeful option for complex cases

“Asherman syndrome is a condition with very limited therapeutic options, especially in moderate and severe cases that do not respond to surgery,” explains Dr. Xavi Santamaria, principal investigator of the project and first author of the study. “In this phase 1/2 trial, the cell therapy developed from the patient’s own cells showed a favourable safety profile, improved the endometrium, reduced adhesions and enabled 30% of patients with no previous reproductive options to have children.”

Cells with clinically based regenerative potential

The cells used in the therapy correspond to a CD133+ subpopulation derived from bone marrow, previously characterised for their regenerative capacity in endometrial tissue, reinforcing their potential as a therapeutic strategy for complex uterine conditions. These cells are obtained through a blood extraction and delivered to the endometrial niche using non-invasive radiological techniques via the arm.

An international collaborative effort

The study was coordinated by researchers from the Carlos Simón Foundation–INCLIVA, in collaboration with the Vall d’Hebron Research Institute (VHIR), the Banc de Sang i Teixits de Barcelona, the University of Valencia, Igenomix R&D, several hospitals in Barcelona and Valencia, and Yale School of Medicine, among other institutions.

Translational research in reproductive health

This research forms part of the endometrial regenerative therapy programme promoted by the Carlos Simón Foundation–INCLIVA, which aims to translate advances in uterine biology and regenerative medicine into new therapeutic options for women with reproductive disorders that are difficult to manage clinically.