Organon has announced plans to discontinue development of OG-6219, its investigational endometriosis treatment, after the Phase 2 ELENA proof-of-concept study failed to meet its primary efficacy endpoint. The decision represents a significant setback for endometriosis drug development, where effective treatment options remain limited.
The randomized, double-blind, placebo-controlled study evaluated OG-6219, an oral 17β-hydroxysteroid dehydrogenase type 1 (HSD17B1) inhibitor, in pre-menopausal women aged 18 to 49 with surgically diagnosed endometriosis and moderate-to-severe pain. The drug failed to demonstrate improvement in endometriosis-related overall pelvic pain compared to placebo.
Organon acquired OG-6219 through its 2021 acquisition of Forendo Pharma, positioning the compound as a potential non-hormonal treatment option for endometriosis pain management. The failure eliminates what had been considered a promising approach to addressing the condition that affects an estimated 10% of reproductive-age women globally.
“While these study results are disappointing, Organon remains committed to our long-term vision to create a better and healthier every day for all women including those living with endometriosis,” said Juan Camilo Arjona Ferreira, M.D., Head of Research & Development and Chief Medical Officer at Organon.
The ELENA study enrolled patients across multiple global centers, testing three different dose levels of OG-6219 administered orally twice daily. The primary endpoint measured changes in mean endometriosis-related overall pelvic pain scores from baseline to the third month of treatment using an eleven-point numerical rating scale.
The discontinuation highlights ongoing challenges in endometriosis drug development, where few pharmaceutical companies pursue dedicated treatments for the condition. Current management options primarily include hormonal therapies and pain medications, with surgical intervention often required for severe cases.
Endometriosis research has historically been underfunded relative to the condition’s prevalence and impact on quality of life. The failure of OG-6219 represents a lost opportunity to provide patients with a novel mechanism of action that could have offered an alternative to existing hormonal treatments.
