Endometriosis - Emerging treatments

Antiprogestins

Gestrinone is a 19-nortestosterone (androgen) derivative with anti-progestagenic properties. It is a long-acting drug that also possesses anti-oestrogenic and anti-gonadotrophic properties.[61][116] Side effects are primarily androgen-excess-related (oily skin, irreversible voice changes, acne). It is not currently available in the US. Mifepristone may improve symptoms of dysmenorrhoea and dyspareunia, although further research is required to determine safety profiles and optimal dosage.[117]

Selective progesterone receptor modulators (SPRMs)

In early clinical trials, SPRMs effectively treated endometriosis-associated pain when compared with controls.[72][118][119] The mechanism of action is thought to be the anti-proliferative actions on the endometrium without suppressing oestrogen production (avoiding vasomotor symptoms and loss in bone mineral density). Progesterone blockade may result in endometrial hyperplasia.

Anti-tumour necrosis factor alpha

Currently, there is insufficient evidence to recommend the use of anti-tumour necrosis factor alpha agents for the relief of pelvic pain in women with endometriosis.[120]

Adjunctive surgical procedures

Adjunctive surgeries that interrupt nerve pathways have been extensively studied in the gynaecological literature. These include laparoscopic uterosacral nerve ablation or LUNA (interrupt bundles that attach to the cervix/uterus) and pre-sacral neurectomy or PSN (interrupt larger, general pathways to the pelvis). Despite the potential benefit seen in small groups of specific cohorts, LUNA and PSN remain investigational procedures.[121][122] There are, however, more recent data that support the use of PSN for central pelvic pain.[123]

Complementary medicines

Side-effect profiles and lack of efficacy of various medicines used to treat endometriosis have motivated women to seek complementary and alternative medicines. One 2016 Cochrane review found limited evidence for the use of vitamin B1 and fish oil, among other supplements, in treating primary dysmenorrhoea, but these findings are limited by a lack of studies, small sample sizes, low quality evidence, and no standardised dosing regimen. Given the studies available for review, there is insufficient evidence to recommend these supplements.[124] Another Cochrane review found that Chinese herbal medication was beneficial in alleviating endometriosis-related pain post-laparoscopy when compared with hormonal therapy. However, further research into the role of complementary medicines is required before they may be considered for use as standard therapy.[124][123]