NICE recommends Yselty®▼ (linzagolix) for symptomatic treatment of endometriosis in women with a history of previous medical or surgical treatment for their endometriosis[i]

London, 1^st May 2025: Theramex is pleased to announce that the National Institute for Health and Care Excellence (NICE) has recommended NHS reimbursement of the extended indication for Yselty^® (linzagolix) for the symptomatic treatment of endometriosis in women with a history of previous medical or surgical treatment for their endometriosis.¹

It is expected that this decision will now enable eligible women across England, Wales and Northern Ireland to access this medicine on the NHS.

Endometriosis is estimated to affect approximately 10% of women of reproductive age,^[ii],[iii] in the UK it is estimated that approximately 1.5 million women (or those assigned female at birth) are living with the condition.² Of these 1.5 million women, it is estimated 13,810 women in England will be eligible for treatment with Yselty^®.^[iv]This figure is only an estimate, however, NICE has recommended Yselty^®  is funded across the NHS for all women who meet the eligibility criteria.¹

If the number of patients satisfying this eligibility criteria exceeds the estimated 13,810 there are no restrictions on the number of women in clinical practice who may be prescribed this treatment. There is enough evidence to show that Yselty^® provides benefits and value for money in the recommended patient population, and can therefore be prescribed routinely across the NHS for these patients.¹

The main clinical consequences of endometriosis are chronic pelvic pain, dysmenorrhoea (painful menstruation) and impaired fertility.³ Symptom severity can range from mild to debilitating. Some women have no symptoms, others have episodic pelvic pain, and still others experience constant pain in multiple body regions.^[v] Symptoms of endometriosis can significantly impact the person’s quality of life (QoL), and their physical and psychosocial functioning, including social life, absenteeism from school or work, intimacy and intimate partnerships, as well as mental health and emotional well-being.^[vi]

The recent publication by Royal College of Obstetricians and Gynaecologists (RCOG),  “Waiting For A Way Forward”, also highlighted that long waiting lists for gynaecology treatment can result in worsening endometriosis for women in the UK.^[vii]

The NICE decision is based on evidence from EDELWEISS 3, a randomised, double-blind and placebo-controlled study to evaluate the safety and efficacy of linzagolix for the treatment of eligible women with moderate-to-severe endometriosis-associated pain.⁸ Treatment with linzagolix 200 mg with add-back therapy (ABT) demonstrated statistically significant reductions in both co-primary endpoints of non-menstrual pelvic pain (NMPP) and dysmenorrhea (DYS) with a stable or decreased use of analgesics compared to placebo.⁸ The most common adverse reactions reported in the endometriosis population treated with the recommended dose of 200 mg with ABT included hot flushes and headache.^[viii]

Tina Backhouse, UK General Manager at Theramex said,

“All women deserve access to the healthcare treatment they need, and they should be empowered to choose what treatment works best for them.

“Unfortunately, there are significant gaps and delays for women in diagnosis and treatment of their endometriosis, which is one of many problems in how women’s health care is provided in the UK.

“This decision by NICE can only be one step in a much longer journey towards equitable treatment for women in the NHS, ensuring that all women, regardless of race or background, receive timely and effective care.”

Emma Cox, Chief Executive at Endometriosis UK said, "Historic lack of research into women's health means those with endometriosis have far too few options for managing their sometimes debilitating pain and other symptoms of endometriosis. It's good to see companies investing in research, and NICE approving a new drug for endometriosis, offering more choice for those considering medical menopause to manage symptoms."

Dr Aziza Sesay, Vice Chair and Creative Director of Black Female Doctors UK and GP with a special interest in Women’s Health said, “It is very encouraging to hear about this latest NICE decision, allowing women suffering from endometriosis access to more treatment options on the NHS. We must continue to advocate for more research, better diagnostic tools, and a broader range of treatment options and cures for women’s and gynaecological health conditions that’s long overdue.”

Dr Lina Antoun, Clinical expert in endometriosis said, “The news of NICE recommending Yselty® for the treatment of endometriosis is an important milestone for women’s health. The availability of this medication offers a new treatment option for eligible patients who have long struggled with pain and limited treatment options. I remain optimistic about the positive impact this decision will have on patients' lives, but we must not lose sight of the ongoing work required to truly transform care for those affected by endometriosis.”

Dame Lesley Regan, Chair of Wellbeing of Women said, “Women should not have to experience pain and hardship because of menstrual health conditions. The latest recommendation from NICE marks a vital move towards providing women with improved access to necessary treatments and care. To address the disparities in gender health, it is essential that we ensure women have access to a variety of effective treatment options that cater to their specific needs.”

▼ This medicine is subject to additional monitoring. This will allow quick identification of new safety information.  

[ii] Endometriosis UK. Endometriosis Facts and Figures [Internet]. [cited 2024 Aug 16]. Available from: https://www.endometriosis-uk.org/endometriosis-facts-and-figures [Accessed April 2025].

[iii] World Health Organization. Fact sheet: Endometriosis [Internet]. 2023 Mar [cited 2024 Aug 15]. Available from: https://www.who.int/news-room/fact-sheets/detail/endometriosis [Accessed April 2025].

[iv] Data on file.

[v] Horne AW, Missmer SA. BMJ 2022;379:e070750;

[vi] Culley L, Law C, Hudson N, Denny E, Mitchell H, Baumgarten M, et al. The social and psychological impact of endometriosis on women’s lives: a critical narrative review. Hum Reprod Update. 2013;19(6):625–39.

[vii] Royal College of Obstetricians and Gynaecologists. (2024). Waiting for a way forward. [Online]. RCOG. Available at: https://www.rcog.org.uk/media/4hnc5qg3/waiting-for-a-way-forward.pdf [Accessed April 2025].