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Abstract
PURPOSE OF REVIEW Condoms and vasectomy are male-controlled family planning methods but suffer from limitations in compliance (condoms) and limited reversibility (vasectomy); thus many couples desire other options. Hormonal male contraceptive methods have undergone extensive clinical trials in healthy men and shown to be efficacious, reversible and appear to be well tolerated. RECENT FINDINGS The success rate of male hormonal contraception using injectable testosterone alone is high and comparable to methods for women. Addition of progestins to androgens improved the rate of suppression of spermatogenesis. Supported by government or nongovernment organizations, current studies aim to find the best combination of testosterone and progestins for effective spermatogenesis suppression and to explore other delivery methods for these hormones. Translation of these advances to widespread use in the developed world will need the manufacturing and marketing skills of the pharmaceutical industry. Availability of male contraceptives to the developing world may require commitments of governmental and nongovernmental agencies. In a time when imbalance of basic resources and population needs are obvious, this may prove to be a very wise investment. SUMMARY Male hormonal contraception is efficacious, reversible and well tolerated for the target population of younger men in stable relationships. Suppression of spermatogenesis is achieved with a combination of an androgen and a progestin. Partnership with industry will accelerate the marketing of a male hormonal contraceptive. Research is ongoing on selective androgen and progesterone receptor modulators that suppress spermatogenesis, minimize potential adverse events while retaining the androgenic and gonadotropin suppressive actions.
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Amory JK, Leonard TW, Page ST, O'Toole E, McKenna MJ, Bremner WJ. Oral administration of the GnRH antagonist acyline, in a GIPET-enhanced tablet form, acutely suppresses serum testosterone in normal men: single-dose pharmacokinetics and pharmacodynamics. Cancer Chemother Pharmacol 2009; 64:641-5. [PMID: 19479252 DOI: 10.1007/s00280-009-1038-1] [Citation(s) in RCA: 25] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/27/2009] [Accepted: 05/14/2009] [Indexed: 11/30/2022]
Abstract
PURPOSE GnRH analogs are useful for the treatment of prostate cancer, but require parenteral administration. The peptide GnRH antagonist acyline potently suppresses luteinizing hormone (LH) and testosterone in man; however, its clinical utility is limited by the requirement for frequent injections. The use of a proprietary enhancer system called GIPET, which is based on medium-chain fatty acids, facilitates the oral bioavailability of peptides. We hypothesized that GIPET enhancement would allow for the safe oral dosing of acyline for the treatment of prostate cancer. METHODS We enrolled eight healthy young men in a pharmacokinetic and pharmacodynamic study of 10, 20 and 40 mg doses of GIPET-enhanced oral acyline. Blood for measurement of serum LH, FSH, testosterone and acyline was obtained prior to each dose of GIPET-enhanced oral acyline and 0.5, 1, 1.5, 2, 3, 4, 6, 8, 12, 24 and 48 h after dosing. RESULTS Serum LH, FSH and serum testosterone were significantly suppressed by all doses of GIPET-enhanced oral acyline after 6 h, with suppression reaching a nadir 12 h after dosing. In addition, the 20 and 40 mg doses demonstrated sustained suppression of testosterone for 12-24 h. All hormone concentrations returned to normal 48 h after administration. There were no treatment-related serious adverse events, and laboratory assessments, including liver function tests and creatinine, were unaffected by treatment. CONCLUSIONS Oral administration of GIPET-enhanced acyline significantly suppresses testosterone and gonadotropins in normal men without untoward side effects and might have utility in the management of prostate cancer.
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Affiliation(s)
- John Kenneth Amory
- Department of Medicine, Division of General Internal Medicine and Endocrinology, Center for Research in Reproduction and Contraception, University of Washington, Seattle, WA 98195, USA.
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3
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Abstract
Gonadotropin-releasing hormone (GnRH) is also known as luteinizing hormone-releasing hormone (LHRH), formerly luteinizing hormone releasing factor (LRF). Since this hormone regulates the secretion of both FSH and LH, we prefer to call it GnRH. GnRH antagonists, as the name implies, are a class of compounds that actively compete with GnRH for the GnRH receptor, thereby neutralizing the effects of GnRH by competitive receptor occupancy. In order to fully appreciate their potential clinical utility, it is first important to comprehend the critical role of GnRH in the regulation of the pituitary-gonadal axis and secondly to familiarize ourselves with the mechanisms of action of GnRH, GnRH agonists and GnRH antagonists.
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Herbst KL, Anawalt BD, Amory JK, Bremner WJ. Acyline: the first study in humans of a potent, new gonadotropin-releasing hormone antagonist. J Clin Endocrinol Metab 2002; 87:3215-20. [PMID: 12107227 DOI: 10.1210/jcem.87.7.8675] [Citation(s) in RCA: 33] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 02/12/2023]
Abstract
Acyline is a novel GnRH antagonist found in animal studies to be a potent suppressor of circulating gonadotropin and testosterone (T) levels. We conducted the first study of acyline administration to humans. Eight healthy, eugonadal young men were administered a series of acyline injections (0, 2.5, 7.5, 25, and 75 microg/kg), each injection separated by at least 10 d. Serum FSH, LH, and T levels were measured for 7 d after injections. Acyline suppressed FSH, LH, and T levels in a dose-dependent fashion. Maximal suppression occurred after injection of 75 microg/kg acyline, which suppressed FSH to 46.9 +/- 2.5%, LH to 12.4 +/- 2.2%, and T to 13.4 +/- 1.4% of baseline levels, maintaining suppression for over 48 h. Serum acyline levels peaked at 1 h at 18.9 +/- 0.9 ng/ml, remained significantly elevated above background 7 d after injection, and returned to background levels by 14-17 d after injection. Side-effects at the site of injection were limited to infrequent blush and pruritus that resolved within 90 min of injection. Higher doses of acyline might be effective as depot injections for long-lasting gonadotropin suppression in hormone-dependent diseases and for use in male hormonal contraception regimens.
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Affiliation(s)
- Karen L Herbst
- Department of Medicine, Division of Metabolism, University of Washington, Seattle, WA 98195, USA.
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5
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Abstract
In spite of the pivotal role FSH plays in the regulation of gametogenesis, we are far from understanding the regulatory mechanisms involved in the control of its synthesis, secretion, and functions. Part of the problem relates to its molecular heterogeneity and the unavailability of assay methods capable of distinguishing the various isoforms of FSH. Recent work has confirmed the existence of two modes of FSH secretion, the basal and the episodic modes. The major portion of FSH secretion appears to be in the basal mode. The episodic mode appears to consist of both GnRH-associated and non-GnRH-associated pulses of FSH. The intracellular mechanisms by which differential release of LH and FSH are facilitated by GnRH are just beginning to be unraveled and may involve different second-messenger systems. Local pituitary regulators such as activins, inhibins, and follistatins are receiving considerable attention in recent years as a means by which differential release of LH and FSH can be facilitated by GnRH and other neuroendocrine factors. In parallel, the search for a selective FSH-releasing factor (FSH-RF) continues. Identification of variant forms of GnRH in recent years has opened up the possibility that one GnRH variant may be the long-sought-after FSH-RF. From a functional aspect, an understanding of how FSH heterogeneity is regulated is also important, as the different mixes of FSH isoforms have the ability to fine-tune the follicular recruitment and selection process. This review focuses on the recent advances made in the neuroendocrine and paracrine regulation of FSH synthesis/secretion/heterogeneity and pinpoints areas of gaps in our knowledge.
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Affiliation(s)
- V Padmanabhan
- Department of Pediatrics and the Reproductive Sciences Program, University of Michigan, Ann Arbor, MI 48109-0404, USA.
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6
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Oxynos C, Wu FC. Male hormonal contraception. BAILLIERE'S BEST PRACTICE & RESEARCH. CLINICAL ENDOCRINOLOGY & METABOLISM 2000; 14:473-87. [PMID: 11097787 DOI: 10.1053/beem.2000.0092] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/11/2022]
Abstract
Male hormonal contraceptive methods are based on the principle of pituitary gonadotrophin suppression and intratesticular testosterone depletion, leading to suppression of spermatogenesis. Following the earlier contraceptive efficacy trials using testosterone alone, synergistic combination regimes using newer androgens and other agents are now being tested. The combination of a long-acting testosterone preparation with a progestogen appears to be the most promising, and will hopefully lead to an accepted product for clinical application early in the 21st century.
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Affiliation(s)
- C Oxynos
- Department of Endocrinology, Manchester Royal Infirmary, Oxford Road, Manchester, M13 9WL, UK
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7
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Oberyé JJ, Mannaerts BM, Kleijn HJ, Timmer CJ. Pharmacokinetic and pharmacodynamic characteristics of ganirelix (Antagon/Orgalutran). Part I. Absolute bioavailability of 0.25 mg of ganirelix after a single subcutaneous injection in healthy female volunteers. Fertil Steril 1999; 72:1001-5. [PMID: 10593371 DOI: 10.1016/s0015-0282(99)00413-6] [Citation(s) in RCA: 47] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/17/2022]
Abstract
OBJECTIVE To assess the absolute bioavailability of ganirelix (Antagon/Orgalutran; NV Organon, Oss, the Netherlands) after a single SC injection. DESIGN Randomized, crossover, pharmacokinetic study. SETTING Phase I clinical research unit. PATIENT(S) Nineteen healthy female volunteers of reproductive age. INTERVENTION(S) Two separate injections of 0.25 mg of ganirelix were given, one subcutaneously and one intravenously, with a washout period of 1 week between injections. Blood samples were taken for assessment of serum ganirelix concentrations, and blood pressure, heart rate, and adverse events were monitored. MAIN OUTCOME MEASURE(S) Pharmacokinetic parameters. RESULT(S) Fifteen subjects were evaluated. The mean concentration-time profile after SC administration was comparable to that after IV administration. The mean (+/- SD) peak concentration and time of occurrence after SC administration were 14.8+/-3.2 ng/mL and 1.1+/-0.3 hours, respectively. The mean (+/- SD) half-lives after IV administration and SC administration were highly similar (12.7+/-3.7 hours and 12.8+/-4.3 hours, respectively). Mean (+/- SD) AUC0-infinity (area under the concentration-time curve) values of 105+/-11 ng/mL x hours and 96+/-12 ng/mL x hours were calculated for IV administration and SC administration, respectively, resulting in an absolute mean (+/- SD) bioavailability of 91.3%+/-6.7%. Both treatments were well tolerated. CONCLUSION(S) Ganirelix is absorbed rapidly and extensively after SC administration, resulting in a high absolute bioavailability of >90%.
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Affiliation(s)
- J J Oberyé
- Research and Development, NV Organon, Oss, The Netherlands.
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8
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Abstract
After almost two decades, the research on LHRH antagonists has produced a number of decapeptides that are currently in clinical studies. The structures of these antagonists, unlike the agonists, differ substantially from that of LHRH. Five of the ten amino acids are unnatural and of D configuration. The structural combination of a hydrophobic N-terminus (residues 1, 2, and 3) and a basic/hydrophilic C-terminus (residues 6 and 8) was thought to be responsible for some HR reactions encountered with the second generation of LHRH antagonists. This side effect was greatly reduced by substituting the appropriate combination of amino acids at positions 5, 6, and 8. The next hurdle in the drug development of LHRH antagonists was solubility and aggregation. In the case of A-75998, water solubility was improved by 12- to 25-fold via substitution of NMeTyr at position 5. However, based on DLS analysis, the aqueous solutions still contained some large aggregates that were not visible to the naked eye. This formation of aggregates was eliminated on formulating A-75998 in Encapsin. In men, a single s.c. dose of 2 mg of A-75998 suppressed T to the castrate levels for over 30 hr. Other LHRH antagonists including ganirelix and cetrorelix are also in phase I/II clinical studies. Clinical studies with cetrorelix in prostate cancer; in vitro fertilization, and benign prostate hypotrophy have been reported.
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Affiliation(s)
- F Haviv
- Abbott Laboratories, North Chicago, Illinois 60064-3500, USA
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Jilma B, Eichler HG, Köppl C, Weber B, Pidlich JP, Ferenci P, Müller C. Effects of testosterone suppression on serum levels of hepatitis B surface antigen and HBV-DNA in men. LIVER 1998; 18:162-5. [PMID: 9716225 DOI: 10.1111/j.1600-0676.1998.tb00144.x] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Abstract
AIMS/BACKGROUND There is epidemiological evidence that progression of hepatitis B virus (HBV)-induced liver disease is adversely influenced by male gender. Furthermore, in male transgenic mice, HBsAg levels increase after puberty, resulting in 4- to 10-fold higher HBsAg levels than in female transgenic mice. Castration reduces HBsAg levels by 90-95%, while substitution of testosterone to castrated animals rapidly increases HBsAg concentrations. We hypothesized that suppression of endogenous testosterone levels may have similar effects on HBsAg serum levels in men, as observed in male mice. METHODS To test our hypothesis, we studied the influence of reversible testosterone suppression by the LHRH-analog triptorelin on serum concentrations of HBsAg and HBV-DNA. Eight male patients, who were chronically infected with HBV, were studied in a prospective interventional study. RESULTS Triptorelin decreased serum testosterone levels to castration levels for several weeks. However, this reversible testosterone suppression had no effect on HBsAg or HBV-DNA serum concentrations (p > 0.05). CONCLUSIONS Suppression of endogenous testosterone levels had no effect on HBsAg levels in men, which points to a different regulation of HBsAg expression in men compared with transgenic mice.
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Affiliation(s)
- B Jilma
- Department of Clinical Pharmacology, Vienna University Hospital School of Medicine, Austria
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10
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Schally AV. Rational use of agonists and antagonists of luteinizing hormone-releasing hormone (LH-RH) in the treatment of hormone-sensitive neoplasms and gynaecologic conditions. Adv Drug Deliv Rev 1997; 28:157-169. [PMID: 10837570 DOI: 10.1016/s0169-409x(97)00056-2] [Citation(s) in RCA: 22] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/19/2022]
Abstract
Analogues of luteinizing hormone-releasing hormone (LH-RH) have made possible new approaches to the treatment of some hormone-dependent cancers and diseases and conditions which result from inappropriate sex hormone levels. In the fields of both gynaecology and oncology, the development of sustained delivery depot systems has played a key role in the clinical use of LH-RH agonists and will be also essential for the LH-RH antagonists. Clinical results show that therapy with agonists of LH-RH is the preferred method of treatment for men with advanced prostate cancer. For prostate cancer and other indications, the new LH-RH antagonists such as Cetrorelix may offer an advantage based on the fact that they inhibit LH, FSH and sex-steroid secretion from the start of the administration and thus reduce the time of the onset of therapeutic effects. The use of antagonists would avoid the temporary clinical "flare-up" of the disease which can occur with the agonists in men with prostate cancer. The rapid shrinkage of the prostate and improvement in urinary symptoms obtained with Cetrorelix in men with benign prostatic hyperplasia (BHP) suggests that LH-RH antagonists offer a therapeutic alternative in patients who are considered poor surgical risks. Various experimental and clinical studies suggest that analogues of LH-RH might be useful for treatment of premenopausal women with oestrogen-dependent breast cancer. LH-RH antagonists such as Cetrorelix could be also considered for hormonal therapy of epithelial ovarian cancer which responds only marginally to the agonists, and for treatment of endometrial cancer. Many investigators have reported beneficial effects of LH-RH agonists in the treatment of patients with leiomyomas. LH-RH antagonists also appear to be promising for therapy of uterine leiomyomas, and in addition might be useful for treatment of endometriosis and polycystic ovarian disease (PCOD). LH-RH agonists have been employed in in vitro fertilization and embryo transfer (IVF-ET) programs to prevent a premature rise in LH and various results suggest that the use of antagonist Cetrorelix in assisted reproduction procedures, could be even more advantageous. For most of these indications, the use of sustained release depot preparations will be required.
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Reissmann T, Klenner T, Deger W, Hilgard P, McGregor GP, Voigt K, Engel J. Pharmacological studies with cetrorelix (SB-75), a potent antagonist of luteinising hormone-releasing hormone. Eur J Cancer 1996; 32A:1574-9. [PMID: 8911120 DOI: 10.1016/0959-8049(96)00138-4] [Citation(s) in RCA: 13] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/03/2023]
Abstract
The antitumour and hormone-suppressive effects of the luteinising hormone-releasing hormone LH-RH antagonist Cetrorelix (D-20761) and its pamoate salt (D-20762) were investigated in the model of the DMBA-induced mammary carcinoma of female rats and by testosterone determinations in normal male rats. Treatment with single high doses of D-20761 induced a rapid decrease of tumour weights with a dose-dependent duration of action. Strong antitumour effects were also observed by applying different multiple dose schedules, including a initial high dose (3.16 mg/kg, s.c.) followed by a low maintenance dose (31.6 micrograms/kg, s.c.). The stability of the molecule against degrading enzymes led to the idea of using the poorly soluble pamoate salt for facilitating a sustained release of active compound. This salt indeed induced a prolonged suppression of tumour growth and of testosterone levels. In conclusion, we found that Cetrorelix is a highly effective LH-RH antagonist which should be further developed for the treatment of hormone-dependent diseases.
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Affiliation(s)
- T Reissmann
- Central Research & Development ASTA Medica AG, Dresden, Germany
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12
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Abstract
With the powerful tools of molecular investigation, the last decade has witnessed the most remarkable scientific advance in our history, yet no new leads for male contraception have been forthcoming. All the likely methods of male contraception discussed above were derived from relatively 'old' physiological principles or serendipitous observations. The increasing gap between fundamental research (in the control of mammalian spermatogenesis) and the lack of clinical application are a testament to the low public funding priority afforded to male reproduction and the unwillingness of the pharmaceutical industry to invest in male reproductive research and development. Yet amidst such an unfavourable setting and with very limited support, it is heartening to note that the prospects of introducing a new systemic method for male contraception into the market by the end of this millenium has been greatly enhanced. Thus the results of recent studies have confirmed the contraceptive efficacy of sex steroid-induced oligozoospermia and unexpectedly revealed an ethnically distinct pattern of susceptibility to the hormonal suppression of spermatogenesis. Thus, Asian men are more responsive than are caucasian, and long-acting testosterone esters now being tested in that most densely populated part of the world may well hasten the large-scale application of this method. This is probably the most effective way to correct the misconceptions that men are unwilling or disinterested in sharing in family planning options with their partners. Together with the increased acceptance of novel non-surgical and reversible methods of vas deferens occlusion and the availability of improved non-latex condoms, the currently unfulfilled contraceptive needs of millions of men can be increasingly met in future years. The consequent increase in overall contraceptive prevalence could well make the telling difference between demographic catastrophe and maintaining good quality existence. Politicians, scientists and industrialists need to wake up to their responsibilities and the opportunities offered by this untapped resource and market potential.
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Affiliation(s)
- F C Wu
- Department of Medicine, University of Manchester, U.K
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13
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Bagatell CJ, Rivier JE, Bremner WJ. Dose effects of the gonadotropin-releasing hormone antagonist, Nal-Glu, combined with testosterone enanthate on gonadotropin levels in normal men. Fertil Steril 1995. [DOI: 10.1016/s0015-0282(16)57670-5] [Citation(s) in RCA: 13] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
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Gonzalez-Barcena D, Vadillo-Buenfil M, Cortez-Morales A, Fuentes-Garcia M, Cardenas-Cornejo I, Comaru-Schally AM, Schally AV. Luteinizing hormone-releasing hormone antagonist cetrorelix as primary single therapy in patients with advanced prostatic cancer and paraplegia due to metastatic invasion of spinal cord. Urology 1995; 45:275-81. [PMID: 7531902 DOI: 10.1016/0090-4295(95)80018-2] [Citation(s) in RCA: 49] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/25/2023]
Abstract
OBJECTIVES To assess the clinical response to luteinizing hormone-releasing hormone (LH-RH) antagonist cetrorelix (SB-75) in patients with advanced carcinoma of the prostate and paraplegia due to metastatic invasion of spinal cord. METHODS Cetrorelix was given at two different dose regimens to 5 patients with prostatic cancer Stage D2 and paraplegia. Urologic and neurologic examinations, laboratory studies, radiography (myelography), and prostate ultrasonography were carried out. Prostate-specific antigen (PSA) and free testosterone were also measured. RESULTS In all patients, the neurologic symptoms regressed. The recovery of the thermic and vibratory sensation and motility of the toes was observed. The neurologic improvement continued during the treatment and at 3 months all the patients were able to walk with the aid of a cane. In 1 patient, the myelography showed that the spinal cord compression had disappeared and prostate volume assessed by ultrasonography showed a significant decrease. The bladder function greatly improved in all 5 patients during the treatment with cetrorelix. Baseline levels of luteinizing hormone fell from 9.28 to 1.0 IU/L and those of follicle-stimulating hormone (FSH) fell from 18.28 to 12 IU/L (P < 0.05) after the first day of therapy with cetrorelix. Mean levels of free testosterone were reduced from 52.4 to 14.7 pmol/L (P < 0.005) at 12 hours and to 13.1 pmol/L (P < 0.005) 3 days after the first injection of cetrorelix. A persistent inhibition of gonadotropins and testosterone was maintained during the subsequent 3 months of therapy. The high levels of PSA gradually decreased. CONCLUSIONS Our results show that LH-RH antagonist cetrorelix causes an immediate lowering of the serum testosterone levels in patients with prostate cancer and metastases in the spinal cord, in whom the LH-RH agonists cannot be used as single drugs because of the possibility of flare-up and appears to be appropriate for long-term therapy.
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Leroy I, d'Acremont M, Brailly-Tabard S, Frydman R, de Mouzon J, Bouchard P. A single injection of a gonadotropin-releasing hormone (GnRH) antagonist (Cetrorelix) postpones the luteinizing hormone (LH) surge: further evidence for the role of GnRH during the LH surge. Fertil Steril 1994; 62:461-7. [PMID: 8062939 DOI: 10.1016/s0015-0282(16)56932-5] [Citation(s) in RCA: 60] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/28/2023]
Abstract
OBJECTIVES To assess the ability of a new third-generation GnRH antagonist, Cetrorelix (Asta Medica AG, Frankfurt am Main, Germany), to postpone the LH surge after a single injection during the late follicular phase. DESIGN A single 5-mg (group 1, n = 7) or 3-mg (group 2, n = 3) dose SC of Cetrorelix was administered during the late follicular phase, on the day of the cycle when plasma E2 exceeded 150 pg/mL (550 pmol/L). Estradiol, LH, FSH, and P levels were measured daily from day 5 of the cycle until day 10 after antagonist administration. Transvaginal ultrasonographies were performed on the day of injection and after antagonist treatment. SUBJECTS Ten normal women with regular ovulatory menstrual cycles. RESULTS In group 1, Cetrorelix was administered on day 14.6 +/- 5 (mean +/- SD) of the cycle, when the mean plasma E2 level was 181 +/- 32 pg/mL (664 +/- 117 pmol/L) (mean +/- SD). Plasma LH and FSH decreased by 56% +/- 19% and 29.5% +/- 16% (mean +/- SD), respectively, reaching the nadir 24 hours after Cetrorelix administration. Estradiol decreased by 85% +/- 17%, reaching the nadir 48 hours after antagonist injection. In group 2, Cetrorelix was administered on day 14.3 +/- 1.2 of the cycle when the mean plasma E2 level was 169 +/- 21 pg/mL (618 +/- 77 pmol/L). Plasma LH and FSH decreased by 66% +/- 18% and 32% +/- 6%, respectively, reaching a nadir 24 hours after Cetrorelix administration. Estradiol decreased by 81% +/- 9%, reaching the nadir 24 to 48 hours after antagonist administration. The LH surge was interrupted in every case. In six of seven subjects from group 1, the LH surge was delayed, occurring 6 to 17 days after the antagonist injection. In the remaining woman, Cetrorelix was administered at the beginning of the LH surge (LH = 13 IU/L): the LH level fell immediately by 54%, and the surge was postponed by 3 days. In group 2, in three of three subjects, the LH surge was delayed, occurring 6 to 9 days after the antagonist injection. No adverse effects were observed, except for very slight and transient erythema and pruritus at the injection site. CONCLUSION Cetrorelix is a very potent new GnRH antagonist. A single injection during the late follicular phase delays the LH surge, even if the latter has already begun. In addition, this new-generation GnRH antagonist is very well tolerated and simple to use. Our data reinforce the role of GnRH during the LH surge and point to a role for new GnRH antagonists in controlled ovarian hyperstimulation to avoid premature LH surges and subsequent luteinization.
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Affiliation(s)
- I Leroy
- Service d'Endocrinologie et des Maladies de la Reproduction, Hôpital Bicêtre, France
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16
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Behre HM, Böckers A, Schlingheider A, Nieschlag E. Sustained suppression of serum LH, FSH and testosterone and increase of high-density lipoprotein cholesterol by daily injections of the GnRH antagonist cetrorelix over 8 days in normal men. Clin Endocrinol (Oxf) 1994; 40:241-8. [PMID: 8137524 DOI: 10.1111/j.1365-2265.1994.tb02475.x] [Citation(s) in RCA: 52] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 01/29/2023]
Abstract
OBJECTIVE Recently we have shown that single dose injections of the new GnRH antagonist cetrorelix ([Ac-D-Na(2)1, D-Phe(4Cl)2, D-Pal(3)3, D-Cit6, D-Ala]GnRH; SB-75) decrease serum LH and testosterone in a dose-dependent manner in normal men. These results prompted us to investigate the effectiveness and safety of multiple daily injections of cetrorelix in normal male volunteers. DESIGN AND VOLUNTEERS Following two control examinations 16 young men were randomly assigned to four study groups (n = 4/group). Daily doses of 0 (placebo), 2, 5, and 10 mg cetrorelix were injected subcutaneously at 0800 h for 8 days and morning and evening blood samples were obtained for 3 weeks. RESULTS One day after the first cetrorelix injection, serum LH and testosterone concentrations were significantly suppressed in all treatment groups. Whereas in the 2 and 5-mg dose groups LH and testosterone showed some fluctuations, daily injections of 10 mg cetrorelix consistently suppressed LH and testosterone in all men. In addition, in this group serum FSH concentrations were significantly suppressed to subnormal values 1 day after the first injection and remained in this range up to 5 days after the last injection. A time and dose-dependent increase of high-density lipoprotein cholesterol was observed during cetrorelix-induced testosterone deprivation with a maximal increase of 0.38 +/- 0.13 mmol/l (14.8 +/- 5.1 mg/dl; mean +/- SEM) in the 10-mg dose group. In addition, parallel to suppressed testosterone the volunteers' libido was significantly reduced under the GnRH antagonist. Apart from those symptoms caused by androgen deficiency, the only adverse side-effect observed was a mild painless local erythema at the injection site that disappeared within an hour. CONCLUSIONS Daily injections of 10 mg cetrorelix effectively and consistently suppress serum LH, FSH and testosterone concentrations, and therefore it has potential for treatment of sex hormone-dependent diseases and for male contraception.
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Affiliation(s)
- H M Behre
- Institute of Reproductive Medicine, University (WHO Collaborating Center for Research in Human Reproduction), Münster, Germany
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17
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Gonzalez-Barcena D, Vadillo-Buenfil M, Gomez-Orta F, Fuentes Garcia M, Cardenas-Cornejo I, Graef-Sanchez A, Comaru-Schally AM, Schally AV. Responses to the antagonistic analog of LH-RH (SB-75, Cetrorelix) in patients with benign prostatic hyperplasia and prostatic cancer. Prostate 1994; 24:84-92. [PMID: 7508623 DOI: 10.1002/pros.2990240206] [Citation(s) in RCA: 77] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 01/25/2023]
Abstract
Among new highly potent antagonistic analogs of luteinizing hormone-releasing hormone (LH-RH), containing neutral hydrophilic D-ureidoalkyl amino acids such as D-Cit and D-Hci at position 6 and free of edematogenic and anaphylactoid reactions, Ac-D-Nal(2)1, D-Ph(4Cl)2, D-Pal(3)3, D-Cit6, D-Ala10 (LH-RH) (SB-75; Cetrorelix) was shown to be one of the most powerful. In this trial, we evaluated the response to 500 micrograms SB-75 given every 12 hr subcutaneously (sc) for 4 weeks in 11 patients with benign prostatic hyperplasia (BPH), and 6 weeks in 6 prostatic cancer patients (2 stage C, 4 stage D2). In patients with BPH presenting with prostatism and urinary outflow obstruction, there was a noticeable clinical improvement after the first week of SB-75 administration. This improvement continued during the course of treatment. Before therapy with SB-75, the serum levels of prostate-specific antigen (PSA) (6.73 +/- 1.46 ng/ml), acid phosphatases, total (12.67 +/- 1.15 U/l), and prostatic (2.27 +/- 0.34 U/l), were mildly elevated, but declined to normal values at 4 weeks: (2.13 +/- 0.59 ng/ml; P < 0.01), (7.68 +/- 0.89 U/l; P < 0.01), and (1.39 +/- 0.18 U/l; P < 0.01), respectively. Mean prostatic volume assessed by ultrasonography showed a significant decrease in all patients from 67.84 +/- 8.86 to 37.92 +/- 8.52 cm3; P < 0.01, which represents a reduction of 44%. In patients with prostate cancer, after the first week of therapy with SB-75, we observed a significant decrease in bone pain, relief in urinary outflow obstruction, and reversal of the signs of prostatism. Subjective improvement continued during the following weeks of treatment, so that the patients no longer needed analgesics. PSA, acid, and alkaline phosphatases gradually fell, achieving nearly normal values at 6 weeks. Initial serum testosterone levels in BPH and prostatic cancer patients were within normal limits, but during treatment with the antagonistic analog SB-75, fell to castration values. A major fall in free testosterone levels was observed after the first dose; the maximal inhibition was seen after 6-12 hr, with a simultaneous decrease in levels of both gonadotropins. Our results show that antagonist SB-75 can be safely administered for prolonged periods of time. The rapid shrinkage of the prostate and concomitant improvement in obstructive symptoms of prostatism obtained with antagonistic analog SB-75 in patients with BPH may decrease the morbidity of prostatic surgery and offer a therapeutic alternative in men who are considered poor surgical risks.(ABSTRACT TRUNCATED AT 400 WORDS)
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Bagatell CJ, Conn PM, Bremner WJ. Single-dose administration of the gonadotropin-releasing hormone antagonist, Nal-Lys (antide) to healthy men. Fertil Steril 1993; 60:680-5. [PMID: 8405525 DOI: 10.1016/s0015-0282(16)56222-0] [Citation(s) in RCA: 22] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/30/2023]
Abstract
OBJECTIVE To evaluate the ability the Nal-Lys GnRH antagonist ([N-Ac-Nal (2)1, 4ClDPhe2, D3Pal3, Lys (Nic)5, D-Lys(Nic)6, Lys (iPr)8, D-Ala10] to suppress gonadotropins and T in humans and to assess its duration of action and its local effects. DESIGN Placebo-controlled clinical study. SETTING A university community. SUBJECTS Seven normal male volunteers. INTERVENTIONS We administered single injections of Nal-Lys (0, 10, 25, and 50 micrograms/kg body weight). Blood samples were collected before and at frequent time intervals after injection. RESULTS Nal-Lys caused only minor local effects. At the higher doses (25 and 50 micrograms/kg), serum LH and T levels were suppressed to 50% to 70% of baseline; serum FSH levels were suppressed to 70% to 80% of baseline, and levels of all three hormones returned to basal values within 24 hours after injection. CONCLUSIONS In humans, Nal-Lys has similar potency and duration of action to other antagonists and produces fewer local side effects. However, the utility of Nal-Lys is limited by formulation difficulties; current efforts are directed at improving the formulation in order to explore the potential clinical uses of this peptide.
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Scott RT, Neal GS, Illions EH, Hayslip CA, Hofmann GE. The duration of leuprolide acetate administration prior to ovulation induction does not impact ovarian responsiveness to exogenous gonadotropins. Fertil Steril 1993; 60:247-53. [PMID: 8339819 DOI: 10.1016/s0015-0282(16)56092-0] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/30/2023]
Abstract
OBJECTIVE To evaluate the possible impact that the duration of GnRH agonist (GnRH-a) suppression has on subsequent ovarian responsiveness to exogenous gonadotropins. DESIGN Prospective evaluation of the relationship between the duration of GnRH-a and multiple parameters of ovarian responsiveness. SETTING Assisted reproduction program in a large military tertiary care center. PATIENTS One hundred sixty-five women being pretreated with leuprolide acetate (LA) before ovulation induction with exogenous gonadotropins. INTERVENTIONS Variable duration of LA administration before stimulation. MAIN OUTCOME MEASURES Outcome measures include duration of stimulation, days until doubling of basal E2, number of ampules of exogenous gonadotropins, peak E2, number of mature follicles, and number of mature oocytes. RESULTS The duration of LA pretreatment had no effect on any of the parameters of ovarian responsiveness analyzed. CONCLUSION Once complete suppression of gonadal function is attained, the duration of GnRH-a suppression has no impact on subsequent ovarian responsiveness to exogenous gonadotropins.
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Affiliation(s)
- R T Scott
- Wilford Hall Medical Center, Lackland AFB, Texas 78236
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Weinbauer GF, Nieschlag E. Comparison of the antigonadotropic activity of three GnRH antagonists (Nal-Glu, Antide and Cetrorelix) in a non-human primate model (Macaca fascicularis). Andrologia 1993; 25:141-7. [PMID: 8517553 DOI: 10.1111/j.1439-0272.1993.tb02698.x] [Citation(s) in RCA: 19] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/31/2023] Open
Abstract
We compared the antigonadotropic activity of the GnRH antagonists Nal-Glu, Antide and Cetrorelix in a non-human primate model (Macaca fascicularis). Orchidectomized animals received a single subcutaneous injection at doses of 250 micrograms kg-1 (n = 4), 625 micrograms kg-1 (n = 4) and 1250 micrograms kg-1 (n = 3) of the compounds Nal-Glu ([Ac-D-Nal(2)1, D-4-Cl-Phe2, D-Pal3, Arg5, D-Glu(AA)6, D-Ala10]-GnRH), Antide (Nal-Lys, [Ac-D-Nal1, D-4-Cl-Phe2, D-Pal3, Nic-Lys5, D-Nic-Lys6, Ip-Lys8, D-Ala10]-GnRH) or Cetrorelix ([Ac-D-Nal1, D-4-Cl-Phe2, D-Pal3, D-Cit6, D-Ala10]-GnRH). Blood samples were collected before and 3, 6, 12, 24, 48, 72, and 96 h after GnRH antagonist administration. Serum was analysed for concentrations of bioactive LH and immunoactive LH and FSH. All three compounds decreased LH secretion within 3-12 h (P < 0.05) and FSH secretion within 12-48 h (P < 0.05) after injection. Major differences between the GnRH antagonists were observed with regard to the effective dose and duration of action. At a dose of 250 micrograms kg-1 Nal-Glu and Antide only transiently suppressed LH and FSH release, whereas Cetrorelix induced complete inhibition (P < 0.05) which lasted for the entire observation period. At a dose of 625 micrograms kg-1 Cetrorelix exhibited the longest duration of action and Nal-Glu the shortest. At the highest dose of 1250 micrograms kg-1 Nal-Glu, Antide and Cetrorelix markedly inhibited LH and FSH secretion throughout the entire study period.(ABSTRACT TRUNCATED AT 250 WORDS)
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Affiliation(s)
- G F Weinbauer
- Institute of Reproductive Medicine of the University, Münster, Germany
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Abstract
GnRH antagonists, unlike GnRH agonists, do not act via "downregulation." Instead, GnRH antagonists monopolize the GnRH receptors to such an extent that endogenous GnRH is unable to bind to sufficient numbers of GnRH receptors to provoke release of LH/FSH. This fundamental difference in the mechanism of action of GnRH antagonists versus GnRH agonists is anticipated to result in clinical benefits for certain applications.
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Affiliation(s)
- K Gordon
- Jones Institute for Reproductive Medicine, Department of Obstetrics and Gynecology, Eastern Virginia Medical School, Norfolk, VA 23507, USA
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22
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Swerdloff RS, Wang C, Bhasin S. Developments in the control of testicular function. BAILLIERE'S CLINICAL ENDOCRINOLOGY AND METABOLISM 1992; 6:451-83. [PMID: 1377467 DOI: 10.1016/s0950-351x(05)80158-2] [Citation(s) in RCA: 23] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/26/2022]
Abstract
Clinicians and clinical investigators have developed improved means for controlling testicular function in men. New and refined approaches for stimulation and inhibition of the hypothalamic-pituitary-testicular axis are now available. This chapter reviewed the most successful ways to inhibit the reproductive axis in men and its current application to the treatment of precocious puberty, metastatic prostate cancer, benign prostate hyperplasia and as prospective male contraceptives. Safe, effective and reversible medical approaches to male contraception are now approaching reality. Azoospermia and severe oligozoo/azoospermia can now be accomplished in the majority of men with combined GnRH antagonists and replacement doses of testosterone. Androgens and androgen-progestogen concentrations will induce azoospermia in over 90% of Asian men and azoospermia or severe oligospermia in Caucasian ethnic groups. Field trials are ongoing to determine whether testosterone administration will be more effective than condoms as contraceptives. True precocious puberty can now be managed more effectively than in the past by suppression of gonadotropin secretion with GnRH analogues. Precocious puberty due to other causes can be treated more effectively with inhibitors of steroidogenesis and blockers of androgen action. Metastatic prostate cancer, previously treatable with either castration or oestrogens, is now amenable to suppression of androgen secretion. GnRH analogues are given either alone or combined with blockers of androgen action. While significant palliative effects are observed with endocrine ablative therapy in most men with Stage C or D prostate cancer, modest increases in duration of survival may be seen. Benign prostate hyperplasia was previously approachable only with surgical intervention. Recent data have suggested that medical treatment with 5 alpha-reductase inhibitors and/or selective alpha-adrenergic blockers may offer non-surgical alternatives in some patients. More data are needed to determine the role of medical management of this common disorder.
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Sharma OP, Weinbauer GF, Behre HM, Nieschlag E. The gonadotropin-releasing hormone (GnRH) agonist-induced initial rise of bioactive LH and testosterone can be blunted in a dose-dependent manner by GnRH antagonist in the non-human primate. UROLOGICAL RESEARCH 1992; 20:317-21. [PMID: 1455564 DOI: 10.1007/bf00922743] [Citation(s) in RCA: 13] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/27/2022]
Abstract
Gonadotropin-releasing hormone (GnRH) agonists induce a clinically undesirable, transitory but very pronounced initial rise of gonadotropin and gonadal steroid secretion. We investigated, in a non-human primate model, whether the initial stimulatory effects of GnRH agonists can be avoided by a short period of pretreatment and simultaneous treatment with a GnRH antagonist. Three groups of five adult male cynomolgus monkeys (Macaca fascicularis) received a single s.c. biodegradable implant loaded with the GnRH agonist, buserelin ([D-Ser(TBu)6-desGly-NH2]-GnRH), releasing approximately 50 micrograms buserelin daily. From 1 week before to 1 week after inception of administration of GnRH agonist, group 1 received the GnRH antagonist vehicle, and groups 2 and 3 were given s.c. injections of the GnRH antagonist Nal-Glu ([Ac-D-Nal(2)1,D-4-Cl-Phe2,D-Pal3,D-Arg5,D-Glu6(AA),D- Ala10]-GnRH) at a dose of 450 or 2250 micrograms/kg daily. In the absence of GnRH antagonist, the GnRH agonist induced a marked elevation of serum luteinizing hormone (LH) and testosterone lasting for 2 and 5 days, respectively. In group 2, Nal-Glu reduced basal hormone secretion and delayed the peak of GnRH-agonist-induced hormone secretion by 1 day. In group 3, the GnRH-agonist-induced rise of LH and testosterone was prevented in three animals and did not exceed baseline hormone levels in the other two animals. Areas under the LH and testosterone curves were significantly reduced in group 3 compared to group 1. After withdrawal of the GnRH antagonist, a second transient rise of hormone secretion was observed. Except for testosterone in group 2, this rise did not exceed the baseline range of hormone concentrations.(ABSTRACT TRUNCATED AT 250 WORDS)
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Affiliation(s)
- O P Sharma
- Institute for Reproductive Medicine, University of Münster, FRG
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Flexible protocol for administration of human follicle-stimulating hormone with gonadotropin-releasing hormone antagonist**Supported in part by the Contraceptive Research and Development (CONRAD) Program, Eastern Virginia Medical School, under a Cooperative Agreement (DPE-2044-A-00-6063-00) with the United States Agency for International Development (A.I.D.). The views expressed by the author(s) do not necessarily reflect the views of A.I.D. Fertil Steril 1992. [DOI: 10.1016/s0015-0282(16)54803-1] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/17/2022]
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Weinbauer GF, Nieschlag E. LH-RH antagonists: state of the art and future perspectives. Recent Results Cancer Res 1992; 124:113-36. [PMID: 1615215 DOI: 10.1007/978-88-470-2186-0_11] [Citation(s) in RCA: 22] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/27/2022]
Affiliation(s)
- G F Weinbauer
- Institut für Reproduktionsmedizin der Universität, WHO Kollaborationszentrum zur Erforschung der männlichen Fertilität, Münster, FRG
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Ditkoff EC, Cassidenti DL, Paulson RJ, Sauer MV, Paul WL, Rivier J, Yen SS, Lobo RA. The gonadotropin-releasing hormone antagonist (Nal-Glu) acutely blocks the luteinizing hormone surge but allows for resumption of folliculogenesis in normal women. Am J Obstet Gynecol 1991; 165:1811-7. [PMID: 1750480 DOI: 10.1016/0002-9378(91)90037-r] [Citation(s) in RCA: 50] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/28/2022]
Abstract
The gonadotropin-releasing hormone antagonist offers several advantages over the use of the agonist and allows several physiologic questions to be addressed. In this study, we evaluated the ability of Nal-Glu to acutely inhibit the luteinizing hormone surge and prevent ovulation. We also assessed whether recovery of the follicle would be possible after several days of gonadotropin deprivation and estradiol decrement. Eight normal ovulatory women were randomized to control or Nal-Glu-treated cycles (50 micrograms/kg intramuscularly) for 3 to 4 days. Monitoring was carried out with daily vaginal ultrasonographic scans and serum estradiol levels and twice-daily serum luteinizing and follicle-stimulating hormone levels. Nal-Glu acutely inhibited the luteinizing hormone surge and ovulation, even when administered as late as the onset of the luteinizing hormone surge. Evidence was provided that spontaneous follicular rescue recurred in eight of 10 cycles after 3 to 4 days of Nal-Glu administration. Although an estradiol to follicular size dissociation occurred with Nal-Glu, subsequent ovulation occurred in 5.1 +/- 0.6 days after the last Nal-Glu dose. The decrement in estradiol after Nal-Glu administration correlated negatively with the days required for subsequent ovulation to occur (r = 0.77, p less than 0.05). The subsequent luteal phase also was normal in terms of length and progesterone levels. These data confirm the potency and efficacy of Nal-Glu in acutely inhibiting gonadotropins and extends our knowledge on the physiologic characteristics of the dominant follicle.
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Affiliation(s)
- E C Ditkoff
- Department of Obstetrics and Gynecology, University of Southern California School of Medicine, Los Angeles
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Salameh W, Bhasin S, Steiner B, McAdams LA, Peterson M, Swerdloff R. Marked suppression of gonadotropins and testosterone by an antagonist analog of gonadotropin-releasing hormone in men**Presented at the 71st Annual Meeting of the Endocrine Society, Seattle, Washington, June 21 to 24, 1989.††Supported by contract N01-HD-6-2935 from the Contraceptive Development Branch, National Institute of Child Health and Human Development (NICHHD), UCLA Population Research Center grant P30-HD19445, NICHHD, Bethesda, Maryland. Fertil Steril 1991. [DOI: 10.1016/s0015-0282(16)54076-x] [Citation(s) in RCA: 19] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/15/2022]
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Large-Scale Synthesis of Gonadotropin-Releasing Hormone Antagonists for Clinical Investigations. ACTA ACUST UNITED AC 1991. [DOI: 10.1016/b978-0-12-185261-0.50006-x] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register]
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29
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Ezan E, Drieu K, Moreau JP, Dray F. Validation in rat plasma of a direct radioimmunoassay for a luteinizing hormone-releasing hormone antagonist (BIM 21009). JOURNAL OF IMMUNOASSAY 1990; 11:295-309. [PMID: 2229420 DOI: 10.1080/01971529008055034] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/30/2022]
Abstract
Rabbits were immunized with [Ac-D-beta-Nal1-, D-p-Cl-Phe2, D-Phe3, D-Arg6, Phe7, D-Ala10]LHRH (BIM 21009) coupled to bovine serum albumin using bis-diazotized benzidine. The best antiserum had an affinity of 5. 10(-10) M and a specificity directed against the C-terminal part of the molecule. The antiserum was not affected by native LHRH but reacted to some extent with detergents. Assay of free-peptide plasma after gel filtration on Ultrogel AcA 34 showed apparent immunoreactivity associated with albumin and lipoproteins. The sensitivity of direct assay was 0.4 ng/ml. Measurements of BIM 21009 after s.c. injection in rats showed the resistance of the peptide to elimination. The specificity of the determinations in plasma were checked by High Performance Liquid Chromatography.
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Affiliation(s)
- E Ezan
- Institut Pasteur, Unité de Radioimmunologie Analytique, Paris, France
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Lahlou N, Delivet S, Bardin CW, Roger M, Spitz IM, Bouchard P. Changes in gonadotropin and α-subunit secretion after a single administration of gonadotropin-releasing hormone antagonist in adult males**Supported in part by grants from the Fondation Isabelle Decazes de Noüe, Lausanne, Switzerland (N.L.); and through cooperative agreement from the United States Agency for International Development, as well as the George J. Hecht Fund, and Andrew W. Mellon and Rockefeller Foundations, New York, New York (P.B.).††Presented at the 71st Annual Meeting of the Endocrine Society, Seattle, Washington, June 21 to 24, 1989. Fertil Steril 1990. [DOI: 10.1016/s0015-0282(16)53529-8] [Citation(s) in RCA: 13] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/17/2022]
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Urban RJ, Pavlou SN, Rivier JE, Vale WW, Dufau ML, Veldhuis JD. Suppressive actions of a gonadotropin-releasing hormone antagonist on luteinizing hormone, follicle-stimulating hormone, and prolactin release in estrogen-deficient postmenopausal women. Am J Obstet Gynecol 1990; 162:1255-60. [PMID: 2111095 DOI: 10.1016/0002-9378(90)90030-b] [Citation(s) in RCA: 16] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/30/2022]
Abstract
We investigated time- and dose-dependent actions of a gonadotropin-releasing hormone antagonist, the "Nal-Glu" peptide [Ac-D2Nal1, 4CIDPhe2, D3Pal3, Arg5, DGlu6(AA), DAla10], in nine healthy estrogen-withdrawn postmenopausal women. Gonadotropin-releasing hormone antagonist was administered subcutaneously at doses of 10, 30, 100, and 300 micrograms/kg. Suppression of immunoactive luteinizing hormone concentrations was achieved with a 30 micrograms/kg dose of antagonist. Suppression of immunoactive follicle-stimulating hormone levels was less (40%) even at the highest antagonist dose (300 micrograms/kg). Bioactive luteinizing hormone concentrations also significantly decreased (greater than 60%) at the two antagonist doses tested (30 and 300 micrograms/kg). However, the lower antagonist dose showed an "escape" of bioactive luteinizing hormone values after 18 hours. No suppressive effects of the antagonist on prolactin secretion occurred at any dose tested. We conclude that this gonadotropin-releasing hormone antagonist can achieve effective, potent, and long-lasting suppression of pituitary secretion of biologically active luteinizing hormone at higher doses, but secretion of biologically active luteinizing hormone may "escape" at lower doses.
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Affiliation(s)
- R J Urban
- Department of Internal Medicine, University of Virginia School of Medicine, Charlottesville 22908
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