GnRH analogs: options for endometriosis-associated pain treatment

Safety and efficacy of elagolix (with and without add-back therapy) for the treatment of heavy menstrual bleeding associated with uterine leiomyomas: a systematic review and meta-analysis

Background

Heavy menstrual bleeding (HMB) is a common clinical finding in patients with uterine leiomyomas that can negatively impact their quality of life. Recently, a novel oral GnRH-antagonist (elagolix) has emerged as a possible therapeutic agent for this ailment. Herein data was pooled from clinical trials assessing the safety and efficacy of elagolix with and without add-back therapy.

Main text

PubMed and Cochrane library were systematically searched for RCTs that measured the efficacy and safety of elagolix for the treatment of uterine fibroid-associated HMB. All safety and efficacy endpoints were compared between elagolix-alone, elagolix w/add-back therapy, and placebo. The primary efficacy endpoint was defined as the number of women who achieved menstrual blood loss (MBL) < 80 ml and a reduction in MBL from baseline of > 50% at the end of treatment. Secondary outcomes assessed included change in hemoglobin levels, incidence suppression of bleeding and amenorrhea, and the incidence of adverse events. The random effects model was used to pool data, and heterogeneity was assessed using I2.

Our search identified 4 clinical trials meeting our PICO criteria, with a total of 916 patients. Analysis of the primary outcome revealed that elagolix-alone was the most effective treatment compared to both placebo (LOR = 3.47, CI = 3.03–3.91, p = 0.000, I2 = 0.0%) and add-back therapy (LOR = 0.64, CI = 0.12–1.16, p = 0.016, I2 = 43.1%). Furthermore, both elagolix groups (irrespective of add-back therapy) observed a significant improvement in post-treatment hemoglobin levels as compared to the placebo group (elagolix-alone vs PBO: LOR = 1.44, CI = 0.66–2.22, I2 = 66.0%, p = 0.000; elagolix-w/add-back therapy vs PBO: LOR = 1.22, CI = 0.78–1.66, I2 = 0.0%, p = 0.000). Concerning safety, while elagolix without add-back therapy had the highest overall incidence of adverse effects (elagolix-alone vs placebo LOR = 0.84, CI = 0.48–1.20, I2 = 7.8%, p = 0.000; elagolix-alone vs elagolix-w/add-back LOR = 0.68, CI = 0.09–1.26, p = 0.024, I2 = 64.6%), the incidence of serious (life threatening) adverse events between all 3 treatment groups was not statistically different. The inclusion of add-back therapy with elagolix made the treatment noticeably safer (elagolix-w/add-back vs placebo: LOR = 0.19, CI = − 0.10 to 0.48, I2 = 0.0%, p = 0.194) without seriously compromising its efficacy.

Conclusion

High-quality evidence from 4 trials suggests that elagolix is an effective treatment for leiomyoma-associated HMB, with a marked improvement in all efficacy endpoints. Furthermore, the inclusion of add-back therapy in the treatment regimen should be considered as it mitigates the hypoestrogenic effects of elagolix.

Endometrial preparation for vitrified-warmed embryo transfer with or without GnRH-agonist pre-treatment in patients with polycystic ovary syndrome: a randomized controlled trial

RESEARCH QUESTION

What are the effects on pregnancy outcome in patients with polycystic ovary syndrome (PCOS) in endometrial preparation cycles for vitrified-warmed embryo transfer with or without gonadotrophin releasing hormone (GnRH) agonist pre-treatment?

DESIGN

A total of 212 patients with PCOS referred to Royan Institute, Tehran, Iran, between 20 August 2017 to 20 June 2018 were included. The patients were randomly assigned to receive oestradiol after downregulation with GnRH agonist (group A) or without GnRH agonist down-regulation (group B).

RESULTS

A total of 188 patients with PCOS completed the trial, 93 patients in group A and 95 patients in group B. Basal oestradiol and LH levels were significantly higher in group B (26.66 versus 41.61, P = 0.01 and 0.93 versus 5.33, P < 0.0001, respectively). Clinical pregnancy rates were not significantly different in both groups (31.2% versus 33.7%). Similarly, no significant differences were found between groups A and B in miscarriage (9.7% versus 11.6%), implantation (0.58 versus 0.51) and live birth (21.7% versus 22.1%) rates and for medical complications during pregnancy and neonatal anomalies.

CONCLUSIONS

Our findings indicate that endometrial preparation for frozen-thawed embryo transfer with and without ovarian suppression by GnRH agonist provides similar results.

Severe ovarian hyperstimulation syndrome associated with long-acting GnRH agonist in oncofertility patients

PURPOSE

To report three cases of severe ovarian hyperstimulation syndrome (OHSS) among oncofertility patients receiving a long-acting GnRH agonist for ovarian suppression after controlled ovarian hyperstimulation (COH) with a GnRH antagonist protocol METHODS: Chart abstraction was completed for three patients at a single academic medical center. Patients included were undergoing fertility preservation prior to gonadotoxic chemotherapy. All patients underwent COH with GnRH antagonist protocol and embryo cryopreservation immediately followed by ovarian suppression with long-acting GnRH agonist. Main outcome measure was development of OHSS.

RESULTS

Despite using GnRH agonist trigger and freezing all embryos, patients developed ascites, intermittent hyponatremia and hemoconcentration consistent with severe early-onset OHSS after receiving long-acting GnRH agonist immediately following oocyte retrieval for ovarian preservation.

CONCLUSIONS

Risk of severe OHSS may be increased when a long-acting GnRH agonist is used for ovarian suppression immediately following oocyte retrieval. A delay in initiating long-acting GnRH agonist after oocyte retrieval in patients at high risk for developing OHSS should be considered.

Triptorelin for the treatment of adenomyosis: A multicenter observational study of 465 women in Russia

Objective

To evaluate the effectiveness of triptorelin for the treatment of adenomyosis, the benign invasion of endometrial tissue into the myometrium, as a fertility‐preserving alternative to the gold standard hysterectomy.

Methods

In this multicenter, open‐label, observational study in Russia, performed from November 3, 2011, to August 24, 2015, we assessed the efficacy and safety of triptorelin 3.75 mg administered intramuscularly every 28 days in Russian women who were gonadotropin‐releasing hormone agonist treatment‐naïve, aged 25–40 years, and had a diagnosis of endometriosis or adenomyosis with heavy menstrual bleeding. We performed a medical record review, interviews to assess symptom severity, and pelvic assessments including transvaginal ultrasound. Data were obtained at first injection of triptorelin (visit 1), on the day of last injection (visit 2), 6 months after last injection (visit 3), and 9 months after last injection (visit 4). Significance was assessed by Wilcoxon signed rank test.

Results

A total of 465 women were included. There was a significant improvement from baseline in severity of heavy menstrual bleeding in 390/463 (84.2%) of women 6 months after last injection (P<0.0001). Severity of dysmenorrhea, abnormal uterine bleeding, and pelvic pain was decreased at visit 3 compared with baseline (P<0.0001). Endometriosis symptoms stopped in 253/262 (96.6%) of women at visit 2 and in 243/263 (92.4%) of women at visit 3. Pregnancy was reported in 116/465 (24.9%) women within 9 months following the end of treatment.

Conclusion

Triptorelin has a favorable safety profile, is highly efficacious in treating clinical symptoms of adenomyosis, and improves reproductive function.

ClinicalTrials.gov registration number: A‐38‐52014‐191, registered October 2011.

Effect of neuromuscular electrical stimulation for endometriosis-associated pain: A retrospective study

This retrospective study evaluated the effect of neuromuscular electrical stimulation (NMES) for the treatment of endometriosis-associated pain (EAP).A total of 154 patients with EAP were included and were divided into 2 groups in this retrospective study. Eighty-three patients were assigned a treatment group, and underwent NMES therapy, while 71 subjects in the control group were at waiting list. The primary outcome of pain was measured by the numerical rating scale (NRS) and the Endometriosis Symptom Severity scale (ESSS). The secondary outcome was quality of life, measured by the 36-Item Short Form Health Survey (SF-36). All outcomes were measured before and after 5-week and 10-week treatment. Moreover, we also recorded the adverse events in this study.After 5-week treatment, no significant differences in all outcome measurements were found between the 2 groups. However, after 10-week treatment, NMES therapy exerted better outcomes in NRS (P = .02), ESSS (P = .04), and SF-36 [Physical Component Summary (PCS), P < .01; Mental Component Summary (MCS), P < .01], compared with the patients at the waiting list. Moreover, no significant differences of all adverse events were found between the 2 groups, although mild and acceptable adverse events occurred in the treatment group.This study demonstrated that NMES is effective for treating patients with EAP.

Dienogest 2 mg Daily in the Treatment of Adolescents with Clinically Suspected Endometriosis: The VISanne Study to Assess Safety in ADOlescents

STUDY OBJECTIVE

To study the safety and efficacy of dienogest 2 mg in adolescents with suspected endometriosis.

DESIGN

A 52-week, open-label, single-arm study.

SETTING

In 21 study centers, in 6 European countries.

PARTICIPANTS

Adolescents aged 12 to younger than 18 years with clinically suspected or laparoscopically confirmed endometriosis.

INTERVENTIONS

Dienogest 2 mg once daily.

MAIN OUTCOME MEASURES

The primary end point was relative change in lumbar spine (L2-L4) bone mineral density (BMD) measured using dual-energy x-ray absorptiometry. A key secondary end point was change in endometriosis-associated pain assessed using a visual analogue scale.

RESULTS

Of 120 patients screened, 111 comprised the full-analysis set (ie, patients who took ≥1 dose of study drug and had ≥1 post-treatment observation) and 97 (87.4%) completed the study. Mean lumbar BMD at baseline was 1.1046 (SD, 0.1550) g/cm². At the end of dienogest treatment (EOT; defined as at 52 weeks or premature study discontinuation), mean relative change in BMD from baseline was -1.2% (SD, 2.3%; n = 103). Follow-up measurement 6 months after EOT in the subgroup with decreased BMD at EOT (n = 60) showed partial recovery in lumbar BMD (mean change from baseline: -2.3% at EOT, -0.6% 6 months after EOT). Mean endometriosis-associated pain score was 64.3 (SD, 19.1) mm at baseline and decreased to 9.0 (SD, 13.9) mm by week 48.

CONCLUSION

In adolescents with suspected endometriosis, dienogest 2 mg for 52 weeks was associated with a decrease in lumbar BMD, followed by partial recovery after treatment discontinuation. Endometriosis-associated pain was substantially reduced during treatment. Because bone accretion is critical during adolescence, results of the VISanne study to assess safety in ADOlescents (VISADO) study highlights the need for tailored treatment in this population, taking into account the expected efficacy on endometriosis-associated pain and an individual's risk factors for osteoporosis.

Minimising menopausal side effects whilst treating endometriosis and fibroids

Medical management of endometriosis and fibroids involves manipulation of the hypothalamic-pituitary-gonadal axis to alter the balance of sex hormones thereby inhibiting disease progression and ameliorate symptoms. Unfortunately, resultant menopausal symptoms sometimes limit the tolerability and duration of such treatment. The use of gonadotrophin-releasing hormone agonists to treat these diseases can result in short-term hypoestrogenic and vasomotor side effects as well as long-term impacts on bone health and cardiovascular risk. The routine use of add-back hormone replacement has reduced these risks and increased patient compliance, making this group of drugs more useful as a medium-term treatment option. The estrogen threshold hypothesis highlights the concept of a 'therapeutic window' in which bone loss is minimal but the primary disease is not aggravated. It explains why add-back therapy is appropriate for such patients and helps to explain the basis behind new developments in the treatment of hormonally responsive gynaecological conditions such as gonadotrophin-releasing hormone antagonists and progesterone receptor modulators.

Incorporating ulipristal acetate in the care of symptomatic uterine fibroids: a Canadian cost-utility analysis of pharmacotherapy management

Objective

To present a Canadian economic evaluation on the cost-utility of ulipristal acetate (5 mg orally daily) compared to leuprolide acetate (3.75 mg intramuscular monthly) in the treatment of moderate-to-severe symptoms of uterine fibroids in women eligible for surgery.

Methods

A probabilistic decision tree was constructed to model the pre-operative pharmacological management of uterine fibroids under the primary perspective of the Ontario public payer. The model parameterized data from clinical trials, observational studies, and public costing databases. The outcome measure was the incremental cost-utility ratio. Uncertainty in the model was explored through sensitivity and scenario analyses.

Results

Ulipristal was associated with faster control of excessive menstrual bleeding, fewer symptoms of hot flashes and lower health care resource consumption. The ulipristal strategy dominated leuprolide as it provided patients with more quality-adjusted life years (0.177 versus 0.165) at a lower cost ($1,273 versus $1,366). Across a range of sensitivity analyses, the results remained robust except to the dose of the comparator drug. If leuprolide was administered at 11.25 mg, once every 3 months, the expected cost for the leuprolide strategy would decline and the associated incremental cost-utility ratio for ulipristal would be $168/quality-adjusted life year.

Conclusion

Ulipristal offers a unique opportunity to effectively and rapidly control menstrual bleeding in patients with uterine fibroids; thereby improving their quality of life while minimizing the probability of moderate-to-severe hot flashes that are common with leuprolide. The current economic analysis suggests that ulipristal remains the dominant strategy across extensive sensitivity analyses.

Gonadotrophin-releasing hormone analogue or dienogest plus estradiol valerate to prevent pain recurrence after laparoscopic surgery for endometriosis: a multi-center randomized trial

OBJECTIVES

To evaluate the efficacy of dienogest + estradiol valerate (E2V) and gonadotrophin-releasing hormone analogue (GnRH-a) in reducing recurrence of pain in patients with chronic pelvic pain due to laparoscopically diagnosed and treated endometriosis.

DESIGN

Multi-center, prospective, randomized study.

SETTING

Three university departments of obstetrics and gynecology in Italy.

POPULATION

Seventy-eight women who underwent laparoscopic surgery for endometriosis combined with chronic pelvic pain.

METHODS

Post-operative administration of dienogest + E2V for 9 months (group 1) or GnRH-a monthly for 6 months (group 2).

MAIN OUTCOME MEASURES

A visual analogue scale was used to test intensity of pain before laparoscopic surgery at 3, 6 and 9 months of follow up. A questionnaire to investigate quality of life was administered before surgery and at 9 months of follow up.

RESULTS

The visual analogue scale score did not show any significant differences between the two groups (p = 0.417). The questionnaire showed an increase of scores for all women compared with pre-surgery values, demonstrating a marked improvement in quality of life and health-related satisfaction with both treatments. No significant differences were found between the groups. The rate of apparent endometriosis recurrence was 10.8% in group 1 and 13.7% in group 2 (p = 0.962).

CONCLUSION

Both therapies seemed equally efficacious in preventing endometriosis-related chronic pelvic pain recurrence in the first 9 months of follow-up.

Elagolix, an oral GnRH antagonist, versus subcutaneous depot medroxyprogesterone acetate for the treatment of endometriosis: effects on bone mineral density

This randomized double-blind study, with 24-week treatment and 24-week posttreatment periods, evaluated the effects of elagolix (150 mg every day, 75 mg twice a day) versus subcutaneous depot medroxyprogesterone acetate (DMPA-SC) on bone mineral density (BMD), in women with endometriosis-associated pain (n = 252). All treatments induced minimal mean changes from baseline in BMD at week 24 (elagolix 150 mg: -0.11%/-0.47%, elagolix 75 mg: -1.29%/-1.2%, and DMPA-SC: 0.99%/-1.29% in the spine and total hip, respectively), with similar or less changes at week 48 (posttreatment). Elagolix was associated with improvements in endometriosis-associated pain, assessed with composite pelvic signs and symptoms score (CPSSS) and visual analogue scale, including statistical noninferiority to DMPA-SC in dysmenorrhea and nonmenstrual pelvic pain components of the CPSSS. The most common adverse events (AEs) in elagolix groups were headache, nausea, and nasopharyngitis, whereas the most common AEs in the DMPA-SC group were headache, nausea, upper respiratory tract infection, and mood swings. This study showed that similar to DMPA-SC, elagolix treatment had minimal impact on BMD over a 24-week period and demonstrated similar efficacy on endometriosis-associated pain.

Elagolix, an Oral GnRH Antagonist for Endometriosis-Associated Pain: A Randomized Controlled Study

OBJECTIVE

The aim of this study was to estimate the efficacy of elagolix, an oral gonadotropin-releasing hormone (GnRH) antagonist, for the treatment of endometriosis-associated pelvic pain.

METHODS

This was a phase II, randomized, placebo-controlled parallel group study conducted at 37 US centers, consisting of an 8-week double-blind period followed by a 16-week open-label period. Patients were 137 women aged 18 to 49, with laparoscopically confirmed endometriosis and moderate to severe nonmenstrual pelvic pain and dysmenorrhea, who were administered elagolix 150 mg daily or placebo. The primary outcomes of the study were the daily assessment of dysmenorrhea, nonmenstrual pelvic pain and dyspareunia using a modified Biberoglu-Behrman scale.

RESULTS

During the double-blind period, there were significantly greater mean reductions from baseline to week 8 in dysmenorrhea (-1.13 ± 0.11 vs. -0.37 ± 0.11, p<0.0001), nonmenstrual pelvic pain (-0.47 ± 0.07 vs. -0.19 ± 0.07, p = 0.0066), and dyspareunia scores (-0.61 ± 0.10 vs. -0.23 ± 0.10, p = 0.0070) in the elagolix group compared with placebo. Continued improvements were observed during the open-label treatment regardless of initial treatment allocation. Elagolix treatment was also associated with significant improvements in quality-of-life measures during the double-blind and open-label periods. The most common adverse events occurring with elagolix were nausea, headache and hot flush, each in 9.9% of patients.

CONCLUSION

Elagolix effectively reduced endometriosis-associated pelvic pain over a 24-week period and was well-tolerated.

Analysis of the levonorgestrel-releasing intrauterine system in women with endometriosis

Objectives

To compare the efficacy, safety and other clinical benefits of the levonorgestrel-releasing intrauterine system (LNG-IUS) and gonadotropin-releasing hormone analogues (GnRH-a) in women with endometriosis.

Methods

A systematic search was carried out using the Cochrane Central Register of Controlled Trials, PubMed, MEDLINE™ and EMBASE databases for all randomized controlled trials (RCTs) that evaluated the use of the LNG-IUS and GnRH-a in premenopausal women with endometriosis.

Results

Five RCTs studies were identified. A meta-analysis showed that, in women with endometriosis, both the LNG-IUS and GnRH-a reduced pain visual analogue scale scores (weighted mean difference [WMD] 0.03 [95% confidence interval [CI] −0.53, 0.59]), serum levels of CA125 (WMD −12.29 [95% CI −29.90, 3.32]), and American Society of Reproductive Medicine staging scores (WMD 1.10 [95% CI −27.98, 30.18]). Psychological and general wellbeing index scores were increased (WMD 1.50 [95% CI −6.19, 9.19]). Levels of low-density lipoprotein cholesterol were also significantly reduced in patients treated with the LNG-IUS (WMD 39.30 [95% CI 6.74, 71.86]).

Conclusions

The LNG-IUS had clinical efficacy equivalent to that of GnRH-a but may have some clinical advantages over GnRH-a in the treatment of endometriosis-associated symptoms. These observations will require further verification in additional studies employing larger patient populations.

Possible involvement of nerve growth factor in dysmenorrhea and dyspareunia associated with endometriosis

Nerve growth factor (NGF) has been recently proposed as one of the key factors responsible not only for promotion of nerve fiber growth but also for the onset and maintenance of pain in a variety of diseases. The aim of this study was to investigate the role of NGF in the pelvic pain associated with endometriosis. Tissue and peritoneal fluid samples were collected from 95 women with laparoscopically and histopathologically confirmed endometriosis and 59 control women without endometriosis. Expression levels of NGF mRNA and protein were examined using real-time RT-PCR and immunohistochemistry, respectively. Concentration of NGF in the peritoneal fluid (PF-NGF) was measured using ELISA. The degree of dyspareunia and dysmenorrhea was evaluated using a verbal rating scale. Real-time RT-PCR analysis revealed that NGF mRNA was significantly more abundant in the ovarian endometriomas and peritoneal endometriosis than in the normal control endometrium. Immunohistochemical analyses demonstrated that NGF was prominently expressed and preferentially localized to the glands of the ovarian endometriomas and peritoneal endometriosis, whereas it was only weakly detectable in the normal endometrium. Although PF-NGF was undetectable in some normal subjects and endometriosis patients, elevated PF-NGF in the peritoneal fluid was more frequently observed in endometriosis patients with severe pain than in those with less severe pain. Our results suggest that NGF produced locally in the peritoneal cavity may be involved in the generation of endometriosis-associated pelvic pain.

Gonadotrophin receptor hormone analogues in combination with add-back therapy: an update

Gonadotrophin receptor hormone analogues (GnRHa) have been used in a range of sex hormone-dependent disorders. In the management of premenstrual syndrome, they can completely abolish symptoms. The success of GnRHa in the treatment of endometriosis and adjuvant therapy in the management of fibroids is proven. This efficacy does not come without a cost and the side-effects of the hypo-estrogenic state have limited their application. The use of add-back therapy to counter these effects has enabled wider application, longer durations of treatment and an increase in compliance. This review article is an update on the evidence supporting gonadotrophin receptor hormone analogues in combination with add-back therapy.

Gonadotrophin-releasing hormone analogues and endometriosis: current strategies and new insights

BACKGROUND

Endometriosis is an estrogen-dependent chronic inflammatory disease affecting 5% to 10% of women in reproductive age and has been reported also in adolescents. Its main clinical presentations are chronic pelvic pain and infertility.

OBJECTIVE

To provide a comprehensive review of the recently published data concerning the mechanism of action of gonadotrophin-releasing hormone analogues (GnRHas) as well as to analyze their role in the management of endometriosis-associated pain and infertility in addition to its value in adolescent cases. Furthermore, to provide practical recommendations and new insights based on the best available information.

METHODS

Systematic search was performed of the Cochrane Library and Medical Literature Analysis and Retrieval System Online database looking for the different trials, reviews and various guidelines relating to GnRHas usage in the management of endometriosis-associated pain, infertility and in adolescent cases.

RESULTS

From a pathophysiological perspective, there is a growing scientific evidence that GnRHas exert its therapeutic effects by their classical pituitary downregulation and via a direct effect on the endometrial cells themselves. Accordingly, they represent an important medical option for the management of different aspects of this enigmatic disease.

CONCLUSION

GnRHas have a valuable strategic role in treatment of endometriosis-associated pain and infertility as well as in adolescents above 16 years.

Treatment of Endometriosis and Chronic Pelvic Pain with Letrozole and Norethindrone Acetate

BACKGROUND

Endometriosis is encountered in 7-10% of actively menstruating women, with a suspected prevalence as high as 22% in asymptomatic women. It is an important cause of chronic pelvic pain. The aim of this study was to evaluate the efficacy and safety of letrozole in combination with norethindrone acetate and calcium in the management of endometriosis associated pelvic pain.

METHODS

Prospective non-randomized open label study was carried out including 20 patients with endometriosis related pelvic pain that was refractory to previous treatments.

RESULT

In all 14 patients completed the study. All patients showed significant improvement of pain scores and revealed significant improvement of features of endometriosis on being given letrozole in combination with norethindrone acetate and calcium.

CONCLUSION

Letrozole is an effective drug for treatment of endometriosis.

Reduced pelvic pain in women with endometriosis: efficacy of long-term dienogest treatment

Purpose

To investigate the efficacy and safety of dienogest as a long-term treatment in endometriosis, with follow-up after treatment discontinuation. The study included women with endometriosis, who had previously completed a 12-week, placebo-controlled study of dienogest, who participated in an open-label extension study for up to 53 weeks. Thereafter, a patient subgroup was evaluated in a 24-week follow-up after treatment discontinuation.

Methods

A multicenter study performed in Germany, Italy and Ukraine. Women with endometriosis were enrolled at completion of the placebo-controlled study (n = 168). All women received dienogest (2 mg once daily, orally) and changes in pelvic pain (on a visual analog scale), bleeding pattern, adverse events and laboratory parameters were evaluated during and after treatment.

Results

The completion rate among women who entered the open-label extension study was 90.5% (n = 152). A significant decrease in pelvic pain was shown during continued dienogest treatment (P < 0.001). The mean frequency and intensity of bleeding progressively decreased. Adverse events, rated generally mild or moderate, led to withdrawal in four patients (2.4%). No clinically relevant changes in laboratory parameters were observed. During treatment-free follow-up (n = 34), the reduction in pelvic pain persisted, while bleeding frequency and intensity returned to normal patterns.

Conclusions

Long-term dienogest showed a favorable efficacy and safety profile, with progressive decreases in pain and bleeding irregularities during continued treatment; the decrease of pelvic pain persisted for at least 24 weeks after treatment cessation.

Gonadotropin-releasing hormone agonist and add-back therapy: what do the data show?

PURPOSE OF REVIEW

Endometriosis is a gynecologic disorder that can lead to debilitating chronic pelvic pain and infertility. Gonadotropin-releasing hormone agonists (GnRHa) have emerged as a primary medical therapy for patients with symptomatic disease, but secondary hypoestrogenic side effects may limit compliance. Add-back therapy is a means of surmounting this problem.

RECENT FINDINGS

Progestins such as norethindrone acetate may be administered with or without addition of low doses of estrogens to safely and effectively extend GnRHa therapy while minimizing side effects. Recent studies have demonstrated that the use of add-back enhances compliance and duration of therapy. The initiation of an add-back should not be deferred given evidence demonstrating an increase in vasomotor symptoms and bone loss if not administered concomitantly. The subset of adolescents with endometriosis who require GnRHa therapy should be administered an add-back, but require careful monitoring of bone mineral density.

SUMMARY

Implementation of an appropriately selected add-back will significantly reduce hypoestrogenic side effects, enhance compliance, and allow for prolongation of therapy without interfering with the efficacy of GnRHa in treating symptomatic endometriosis.

Endometriosis: current therapies and new pharmacological developments

Endometriosis is a chronic inflammatory condition that is responsive to management with steroids. The establishment of a steady hormonal environment and inhibition of ovulation can temporarily suppress ectopic implants and reduce inflammation as well as associated pain symptoms. In terms of pharmacological management, the currently available agents are not curative, and treatment often needs to be continued for years or until pregnancy is desired. Similar efficacy has been observed from the various therapies that have been investigated for endometriosis. Accordingly, combined oral contraceptives and progestins, based on their favourable safety profile, tolerability and cost, should be considered as first-line options, as an alternative to surgery and for post-operative adjuvant use. In situations where progestins and oral contraceptives prove ineffective, are poorly tolerated or are contraindicated, gonadotrophin-releasing hormone analogues, danazol or gestrinone may be used. Future therapeutic options for managing endometriosis must compare favourably against existing agents before they can be considered for inclusion into current practice. Finally, as reproductive prognosis is not ameliorated by medical treatment, it is not indicated for women seeking conception.

New drugs in development for the treatment of endometriosis

Endometriosis is a common and enigmatic disease causing pelvic pain and infertility. Current treatment is mainly based on the use of surgery and ovarian suppressive agents. There is in particular the need for new therapeutic options able to allow a normal menstrual cycle to occur and also consent pregnancy. In the present review, we aimed to give a concise and practical overview in order to allow the clinician to clearly understand the level of development of these drugs. We have presented only treatments supported by in vivo researches with a special attention to studies in humans. Results show appealing new possibilities are emerging from agents counteracting the endometriosis-associated inflammation. Recent data also suggests that there is still the opportunity to refine the use of already available agents.

Impact of GnRH agonist treatment on recurrence of ovarian endometriomas after conservative laparoscopic surgery

OBJECTIVE

To analyze the influence of postoperative GnRH agonist treatment on disease recurrence after conservative laparoscopic surgery for ovarian endometriomas according to duration of the treatment.

DESIGN

Retrospective cohort study.

SETTING

University hospital.

PATIENT(S)

One hundred nine consecutive premenopausal women who underwent conservative laparoscopic surgery for ovarian endometriomas (endometriosis stage III/IV) were enrolled in the study. The patients were divided into four treatment groups: expectant management (n = 37) and GnRH agonist therapy for 3 (n = 28), 4 (n = 21), and 6 months (n = 23).

INTERVENTION(S)

None.

MAIN OUTCOME MEASURE(S)

An ultrasound confirmed recurrence of ovarian endometriomas.

RESULT(S)

The overall crude recurrence rate was 16.5% after follow-up for an average of 20.1 months. The crude recurrence and the cumulative probabilities of disease recurrence at 24/36 months tended to be lower in patients who received a GnRH agonist for 6 months (4.3%, 5.3%/5.3%) compared with those who received it for 3 months (17.9%, 12.5%/25.0%) and 4 months (28.6%, 18.9%/39.2%) and patients with expectant management (16.2%, 22.4%/37.9%). However, the differences did not reach statistical significance.

CONCLUSION(S)

Treatment with GnRH agonist for six months had a beneficial impact on the recurrence rate after conservative laparoscopic surgery for ovarian endometriomas.

Treatment strategies for endometriosis

BACKGROUND

Endometriosis is a common chronic disease that causes symptoms of pain and infertility. The pain syndrome can be quite incapacitating. The pain symptoms usually originate in the reproductive organs but can also involve the urinary or intestinal tracts if endometriosis implantation has occurred there. The presentation and physical appearance of endometriosis is extremely variable and can be characterized by a chronic intraperitoneal inflammatory process and adhesions. The only definitive diagnostic technique is laparoscopy.

OBJECTIVE

To review current literature on the treatment strategies for endometriosis.

METHODS

Review of Pubmed, Cochrane database and Medline for current review articles and studies regarding the current treatment strategies for endometriosis.

RESULTS

Initial treatment is surgical or medical. Medical therapy is often used as a first-line therapy and can also be used in conjunction with those patients who undergo surgical therapy for pain. No medical therapy has proven effective for infertility. Medical therapy consists mostly of hormonal suppressive therapy in which the medication causes a downregulation of the hypothalamus-pituitary-ovarian pathway. Non-steroidal anti-inflammatory drugs and oral contraceptives are often used as an initial approach even without a definitive diagnosis. Progestins, such as oral norethindrone and depot medroxyprogesterone, are effective while using them but have a high recurrence rate. The norgestrol intrauterine device is also quite effective at relieving pain associated with endometriosis, especially pain arising during menses as well as from lesions in the rectovaginal tissue. Gonadotropin-releasing hormone agonists induce a pseudomenopausal state and have significant side effects, such as hot flashes and genital atrophy. 'Add-back' therapy with a progestin has been shown to relieve most of these drug related symptoms. Gonadotropin-releasing hormone agonists are also very effective at relieving symptoms of pain during treatment but are also associated with a high recurrence rate. New drug therapies that are under investigation are aromatase inhibitors and immunomodulators. Furthermore, new delivery systems are being investigated that may also improve the patient response.

Inflammatory status influences aromatase and steroid receptor expression in endometriosis

Aberrant up-regulation of aromatase in eutopic endometrium and implants from women with endometriosis has been reported. Aromatase induction may be mediated by increased cyclooxygenase-2 (COX-2). Recently, we demonstrated that progesterone receptor (PR)-A and PR-B serve an antiinflammatory role in the uterus by antagonizing nuclear factor kappaB activation and COX-2 expression. PR-C, which antagonizes PR-B, is up-regulated by inflammation. Although estrogen receptor alpha (ERalpha) is implicated in endometriosis, an antiinflammatory role of ERbeta has been suggested. We examined stage-specific expression of aromatase, COX-2, ER, and PR isoform expression in eutopic endometrium, implants, peritoneum, and endometrioma samples from endometriosis patients. Endometrial and peritoneal biopsies were obtained from unaffected women and those with fibroids. Aromatase expression in eutopic endometrium from endometriosis patients was significantly increased compared with controls. Aromatase expression in endometriosis implants was markedly increased compared with eutopic endometrium. Aromatase mRNA levels were increased significantly in red implants relative to black implants and endometrioma cyst capsule. Moreover, COX-2 expression was increased in implants and in eutopic endometrium of women with endometriosis as compared with control endometrium. As observed for aromatase mRNA, the highest levels of COX-2 mRNA were found in red implants. The ratio of ERbeta/ERalpha mRNA was significantly elevated in endometriomas compared with endometriosis implants and eutopic endometrium. Expression of PR-C mRNA relative to PR-A and PR-B mRNA was significantly increased in endometriomas compared with eutopic and control endometrium. PR-A protein was barely detectable in endometriomas. Thus, whereas PR-C may enhance disease progression, up-regulation of ERbeta may play an antiinflammatory and opposing role.