Is drug-induced bone loss acceptable in premenopausal women? A practical fracture risk modeling exercise

Bone Mineral Density Changes Associated With Pregnancy, Lactation, and Medical Treatments in Premenopausal Women and Effects Later in Life

Bone mineral density (BMD) changes during the life span, increasing rapidly during adolescence, plateauing in the third decade of life, and subsequently entering a phase of age-related decline. In women, menopause leads to accelerated bone loss and an increase in fracture risk. Between peak bone mass attainment and menopause, BMD is generally stable and the risk of fracture is typically low. This time period is marked by life events such as pregnancy and lactation, which transiently decrease BMD, yet their long-term effects on fracture risk are less certain. BMD may also be altered by exposure to medications that affect bone metabolism (e.g., contraceptives, glucocorticoids, antidiabetic medications, antiepileptic drugs). Although oral contraceptives are often believed to be neutral with regard to bone health, depot medroxyprogesterone acetate (DMPA) and gonadotropin-releasing hormone (GnRH) agonists have been associated with decreases in BMD. Development of newer medical therapies, principally GnRH antagonists (e.g., ASP1707, elagolix, linzagolix, relugolix), for treatment of endometriosis-associated pelvic pain and heavy menstrual bleeding due to uterine fibroids has renewed interest in the short- and long-term impacts of changes in BMD experienced by premenopausal women. It is important to understand how these drugs influence BMD and put the findings into context with regard to measurement variability and naturally occurring factors that influence bone health. This review summarizes what is known about the effects on bone health pregnancy, lactation, and use of DMPA, GnRH agonists, and GnRH antagonists in premenopausal women and potential consequences later in life. ClinicalTrials.gov identifier: NCT03213457.

Integrating real-world data and modeling to project changes in femoral neck bone mineral density and fracture risk in premenopausal women

Decline of bone mineral density (BMD) during menopause is related to increased risk of fractures in postmenopausal women, however, this relationship in premenopausal women has not been established. To quantify this relationship, real-world data (RWD) from the National Health and Nutrition Examination Survey (NHANES), and longitudinal data from the elagolix phase III clinical trials were modeled across a wide age range, and covariates were evaluated. The natural changes in femoral neck BMD (FN-BMD) were well-described by a bi-exponential relationship with first-order BMD formation (k₁ ) and resorption (k₂ ) rate constants. Body mass index (BMI) and race (i.e., Black) were significant predictors indicating that patients with high BMI or Black race experience a relatively lower BMD loss. Simulations suggest that untreated premenopausal women with uterine fibroids (UFs) from elagolix phase III clinical trials (median age 43 years [minimum 25-maximum 53]) lose 0.6% FN-BMD each year up to menopausal age. For clinical relevance, the epidemiological FRAX model was informed by the simulation results to predict the 10-year risk of major osteoporotic fracture (MOF). Premenopausal women with UFs, who received placebo only in the elagolix phase III trials, have a projected FN-BMD of 0.975 g/cm² at menopause, associated with a 10-year risk of MOF of 2.3%. Integration of modeling, RWD, and clinical trials data provides a quantitative framework for projecting long-term postmenopausal risk of fractures, based on natural history of BMD changes in premenopausal women. This framework enables quantitative evaluation of the future risk of MOF for women receiving medical therapies (i.e., GnRH modulators) that adversely affect BMD.

A Personalized Medicine Approach Using Clinical Utility Index and Exposure-Response Modeling Informed by Patient Preferences Data

Selection of a personalized dose for an individual patient can be informed by the patient's preferences, translated as weights on each of the clinically relevant safety and efficacy drug attributes, based on results from a brief patient preference elicitation questionnaire. In this analysis, the weighted attributes were simulated to represent various endometriosis patient profiles. Exposure-response simulations were performed for elagolix, a drug approved for management of moderate to severe pain associated with endometriosis, across a range of plasma exposures corresponding to a range of doses. The results were combined to calculate a personalized clinical utility index. An interactive user-friendly online application was developed and envisioned as a physician's desk tool to personalize the dose selection process based on individual patient preferences. This demonstration should serve as an example of how patient/physician conversation can be facilitated with quantitative tools for personalizing the dose.

Estimating the Effect of Elagolix Treatment for Endometriosis on Postmenopausal Bone Outcomes: A Model Bridging Phase III Trials to an Older Real-World Population

Elagolix, a gonadotrophin‐releasing hormone antagonist, is used in premenopausal women with endometriosis. There is a risk of bone loss with elagolix, but the long‐term effects of BMD loss later in life cannot be directly assessed and has not been quantified. To address this gap in knowledge, this study indirectly estimated the impact of elagolix on postmenopausal fracture risk. BMD change in premenopausal women with endometriosis treated with elagolix was modeled from the phase III program data (elagolix group) and used to simulate treatment effects on (fracture risk assessment tool estimated) 10‐year risks of hip and major osteoporotic fracture in women ages 50 to 79 years from the 2005–2010 National Health and Nutrition Examination Survey (NHANES; N = 2303). Change in the proportion of women reaching risk‐based antiosteoporotic treatment thresholds was also estimated. For elagolix versus NHANES, median 10‐year risk of major osteoporotic fracture was 4.73% versus 4.70% in women ages 50 to 59 years, 7.03% versus 6.97% in women ages 60 to 69 years, and 10.83% versus 10.68% in women ages 70 to 79 years. Median 10‐year risk of hip fracture in these same groups was 0.19% versus 0.18% for women ages 50 to 59 years, 0.51% versus 0.49% for women 60 to 69 years, and 2.22% versus 2.14% for women 70 to 79 years. The proportion of women reaching risk‐based antiosteoporotic treatment thresholds caused by elagolix 150 mg daily for 12 months was 0.36% higher at age 50 to 59 years, 0.23% at age 60 to 69 years, and 1.79% at age 70 to 79 years. The number needed to harm was 643 for one additional hip fracture and 454 for one additional major osteoporotic fracture. Results were similar for elagolix 200 mg twice a day for 3 months. In the modeled scenarios, elagolix had minimal impact on long‐term risk of fracture and reaching risk‐based treatment thresholds. © 2020 The Authors. JBMR Plus published by Wiley Periodicals, Inc. on behalf of American Society for Bone and Mineral Research © 2020 The Authors. JBMR Plus published by Wiley Periodicals LLC on behalf of American Society for Bone and Mineral Research.

Efficacy and safety of ASP1707 for endometriosis-associated pelvic pain: the phase II randomized controlled TERRA study

STUDY QUESTION

Does the GnRH antagonist, ASP1707, reduce endometriosis-associated pelvic pain?

SUMMARY ANSWER

ASP1707 significantly reduced endometriosis-associated pelvic pain in a dose-related manner

WHAT IS KNOWN ALREADY

GnRH agonists are an effective therapeutic option for endometriosis that is refractory to non-steroidal anti-inflammatory drugs, oral contraceptives, and progestins. However, GnRH agonists cause complete suppression of estradiol (E2), resulting in hypoestrogenic side-effects such as bone loss that may increase the future risk of osteoporotic fractures.

STUDY DESIGN, SIZE, DURATION

This was a Phase II, multicenter, double-blind, randomized, parallel-group, placebo-controlled study conducted in 540 women from 04 December 2012 to 30 July 2015 in Europe and Japan. A sample size of 504 (84 subjects per group) was calculated to provide ≥80% power to detect a dose-related treatment effect among placebo and ASP1707 doses in change from baseline in pelvic pain, assuming different dose–response curves after 12 weeks of treatment.

PARTICIPANTS/MATERIALS, SETTING, METHODS

Of 912 women with endometriosis-associated pelvic pain screened, 540 were enrolled, and 532 received ≥1 dose of study drug (placebo, n = 88; ASP1707 3 mg, n = 86; ASP1707 5 mg, n = 91; ASP1707 10 mg, n = 90; ASP1707 15 mg, n = 88; leuprorelin, n = 89) for 24 weeks.

MAIN RESULTS AND THE ROLE OF CHANCE

After 12 weeks of treatment with ASP1707, the mean (95% CI) changes in numeric rating score (NRS) for overall pelvic pain (OPP) were −1.56 (−1.91, −1.21), −1.63 (−1.99, −1.27), −1.93 (−2.27, −1.60), −2.29 (−2.64, −1.94), and −2.13 (−2.47, −1.79) for placebo, ASP1707 3 mg, ASP1707 5 mg, ASP1707 10 mg, and ASP1707 15 mg, respectively. Mean (95% CI) changes in NRS for dysmenorrhea were −1.50 (−2.00, −1.00), −2.72 (−3.22, −2.21), −2.85 (−3.33, −2.38), −3.97 (−4.46, −3.48), and −4.18 (−4.66, −3.70), respectively. Mean (95% CI) changes in NRS for non-menstrual pelvic pain (NMPP) were −1.53 (−1.88, −1.19), −1.51 (−1.87, −1.16), −1.80 (−2.14, −1.47), −2.03 (−2.37, −1.68), and −1.86 (−2.20, −1.52), respectively. Statistically significant dose-related treatment effects in reduction in NRS for OPP (P = 0.001), dysmenorrhea (P < 0.001), and NMPP (P = 0.029) were observed after 12 weeks among ASP1707 doses and were maintained through 24 weeks. Serum estradiol and bone mineral density decreased dose dependently with ASP1707 through 24 weeks, however, to a lesser extent than with leuprorelin.

LIMITATIONS, REASON FOR CAUTION

This study was not powered for pairwise comparison of each ASP1707 group versus placebo.

WIDER IMPLICATIONS OF THE FINDINGS

All doses of ASP1707 reduced serum E2 levels to within the target range and to a lesser extent than leuprorelin. ASP1707 is a potential alternative treatment to leuprorelin for endometriosis-associated pelvic pain with lower impact on bone health.

STUDY FUNDING/COMPETING INTEREST(s)

This study was funded by Astellas Pharma Inc. T.D’.H is Vice President and Head of Global Medical Affairs Fertility at Merck, Darmstadt, Germany since October 1, 2015. At the time that the TERRA study was conducted, he served as Principal Investigator in his role as Coordinator of the Leuven University Fertility Center. Since October 2015, T.D’.H has left Leuven University Hospital Gasthuisberg, but continues to serve as Professor in Reproductive Medicine and Biology at KU Leuven (University of Leuven) Belgium and at the Dept of Obstetrics, Gynecology and Reproduction at Yale University, New Haven, USA. T. Fukaya and Y. Osuga report personal consulting fees from Astellas Pharma Inc. during the conduct of the study and outside the submitted work. G.M. Holtkamp, and L. Skillern are employed by Astellas Pharma Europe B.V.; K. Miyazaki is employed by Astellas Pharma Inc.; B. López, was a biostatistician for Astellas Pharma Europe B.V. during conduct of the study; R. Besuyen was a contract Associate Director of Medical Science for Astellas during conduct of the study.

TRIAL REGISTRATION NUMBER

ClinicalTrials.gov, www.clinicaltrials.gov, NCT01767090. EudraCT number 2012-002791-14.

TRIAL REGISTRATION DATE

18 December 2012.

DATE OF FIRST SUBJECT’S ENROLLMENT

One subject signed informed consent on 04 December 2012; the first subject was randomized on 16 April 2013.

Short- and long-term impact of gonadotropin-releasing hormone analogue treatment on bone loss and fracture

Gonadotropin-releasing hormone analogues (GnRH-a) are commonly utilized in moderate to severe endometriosis to induce atrophy of endometriotic lesions. Unfortunately, cessation of therapy can lead to recurrence of symptoms. Therefore, long term therapy is sometimes necessary. GnRH analogues cause an immediate decrease in bone mineral density which usually recovers after cessation of its use. However, this recovery in bone mineral density may not always occur after long term use. In order to prevent the deleterious effects on bone, add-back therapy is used frequently. This review will explore the impact of GnRH analogues on both bone loss and fracture risk as well as describe different add-back regimens.