March has been recognized globally as Endometriosis awareness month, which is an excellent reason to draw more attention to this extremely serious and debilitating health condition.
Endometriosis is the disease characterized by the presence of endometrium outside the uterine cavity. Most often it affects the ovaries, fallopian tubes and lining of the pelvis. In some cases it can also appear on bowel and bladder and in rare cases lesions can be found well outside pelvis (e.g. in lungs, skin etc). The exact cause of endometriosis is unknown. However, some possible causes include: immune systems condition, endometrial cell transport, retrograde menstruation etc.This condition affects huge number of female patients – around 10% (190 mln) of reproductive age women worldwide (Horne A. et al, 2022, Wang Z. et al, 2025, WHO data, 2025). It is often accompanied by an inflammatory response and cause a wide range of symptoms, main one being a pelvic pain (including dysmenorrhea, non-menstrual pelvic pain, and dyspareunia) which is reported in up to 90% of patients (Az-Sanie S. et al, 2025), it also affects reproductive function – 26-50% of women with endometriosis report infertility (Bailleul A. et al.,2021, Az-Sanie S. et al, 2025, Coccia M.E., 2022). In addition, women with endometriosis quite frequently experience increased rates of anxiety, depression, and various other mental health conditions (Lagana A et al, 2017). Overall, endometriosis seriously impacting quality of life and well-being of affected women.Another issue is that individuals with symptoms may not be aware of the condition and some can be completely asymptomatic for long time. Access to early diagnosis and effective treatment of endometriosis differ from country to country and can be limited in many settings, especially in low- and middle-income countries. According to WHO data, currently the average time to diagnosis can be between 4 and 12 years.
For several decades laparoscopy was considered the gold standard in endometriosis diagnosis, however it’s an invasive procedure which is also relatively expensive. This is the reason that recently more and more physicians are relying on patients complaints, symptoms and clinical examination, combined with TVUS/MRI to determine the diagnosis. In 2022, ESHRE (European Society of Human Reproduction and Embryology) in their updated guidelines accepted this approach and no longer considering laparoscopy as sole gold standard for diagnosis. Instead, the guidelines prioritize high-quality imaging, such as transvaginal ultrasound or MRI, for diagnosing deep infiltrative and ovarian endometriosis. Laparoscopy is now recommended primarily for patients with negative imaging or when empirical treatments are ineffective.
In terms of treatment – there are conservative and surgical options, however, unfortunately, as of today none of those are definitively curing the disease. Instead, treatments are based on severity, individual preferences, side effects, long-term safety, costs, availability and whether pregnancy is desired.
Conservative treatment options can include:
● non-steroidal anti-inflammatory drugs (NSAIDs) such as ibuprofen, naproxen and other analgesics, which are often used to treat pain;
● hormonal medicines: combined hormonal contraceptives, progestins (including hormonal IUDs), GnRH agonists/antagonists
Also, aromatase inhibitors can be considered, however as of now only for off-label use as none of those are approved for the treatment of endometriosis.
However, some of these methods may not be suitable for women who want to get pregnant.
Surgical treatment can remove endometriosis lesions, adhesions, and scar tissue. Hysterectomy (surgical removal of the uterus), usually with the removal of the ovaries, may be considered for individuals who do not respond to other treatments and are not planning to have a child. However, hysterectomy is not a cure, and some patients may have symptoms that remain. In certain cases, surgical treatment can be combined with conservative one.
Success in reducing pain symptoms and increasing pregnancy rates through surgery are often dependent on the extent of disease. In addition, lesions may recur even after successful eradication, and pelvic floor muscle abnormalities can contribute to chronic pelvic pain.
With all mentioned above it’s evident that in such circumstances, when disease burden is so high and there is no real curative option, there is a huge unmet need. That is why endometriosis continues to be very important indication for clinical trials. Some companies continue to develop further existing options (e.g. GnRH-antagonists), while also many pharmaceutical companies starting early phase trials to develop new treatment options (e.g. aromatase inhibitors, SERMs (selective estrogen receptor modulators, non-hormonal options centrally targeting pain etc).
At the same time clinical trials in endometriosis are very demanding – as although number of potential patients is quite high, certain peculiarities of the disease and study design can be challenging for:
● recruitment (e.g. even despite ESHRE guidelines no longer considering surgical diagnosis as mandatory, not all RAs are accepting this – US FDA for example still mandatory requires surgical confirmation as inclusion criterion making conduct of endometriosis studies in US these days much more challenging)
● retention – studies in this indication are usually quite long and almost always placebo-controlled, so keeping patients engaged during the whole study course is very important task
● data collection – pain is serving as primary endpoint in almost all endometriosis trials and being collected through PRO (patient reported outcomes) so proper training and diary completion by patients are very important
● site engagement – again due to long study duration and usually quite long recruitment period, it is of utmost importance to keep sites engaged and involved
PVR team is well aware of all the challenges endometriosis studies can bring, our employees did have experience in successfully running complex endometriosis programs. We understand disease, patient pathways, can help with protocol development, have relationships with sites and KOLs, able to offer dedicated project teams and ensure on-time and cost-effective delivery, so will be happy for the opportunity to partner with pharmaceutical companies in advancing their innovative endometriosis research with ultimate goal to bring new curative options for women around the world suffering from endometriosis.
.png)
.svg)
.svg)
.svg)
