A randomized three-way cross-over study in healthy pituitary-suppressed women to compare the bioavailability of human chorionic gonadotrophin (Pregnyl) after intramuscular and subcutaneous administration

Analytical Investigation of the Profile of Human Chorionic Gonadotropin in Highly Purified Human Menopausal Gonadotrophin Preparations

Highly purified human menopausal gonadotropin (HP-hMG [Menopur®, Ferring Pharmaceuticals, Saint-Prex, Switzerland]) contains a 1:1 ratio of follicle-stimulating hormone (FSH) and luteinizing hormone (LH). This analysis aimed to assess gonadotropin (FSH, LH and hCG) abundance in HP-hMG and clarify the source of hCG by assessing the presence of sulfated glycans, which are diagnostic for pituitary hCG forms due to their distinct glycosylation patterns. Additionally, the purity of each sample, their specific components, and their oxidation levels were assessed. HP-hMG samples (three of Menopur® and two of Menogon® Ferring Pharmaceuticals, Saint-Prex, Switzerland) were included in the current analyses. Brevactid® (urinary hCG; Ferring Pharmaceuticals, Saint-Prex, Switzerland) and Ovidrel® (recombinant hCG; Merck KGaA, Darmstadt, Germany) were used as control samples. Glycopeptide mapping and analysis of impurities were carried out by liquid chromatography-tandem mass spectrometry (LC-MS/MS). Oxidation was assessed through reducing peptide mapping using LC-MS/MS. The FSH and LH in the HP-hMG samples showed sulfated glycans, while no signals of sulfated glycopeptides were detected on any site of the beta subunit of hCG. HP-hMG test samples presented the same hCG glycan distribution as the control sample (placental hCG, Brevactid®) extracted from the urine of pregnant women, suggesting a non-pituitary source of hCG. Protein impurities were estimated to constitute approximately 20-30% of the entire HP-hMG protein content in the test samples. More than 200 non-gonadotropin proteins were identified in the HP-hMG test samples, of which several were involved in embryonic development or pregnancy. The alpha subunit of the tested samples was strongly oxidized, with a relative abundance of 20% of the total gonadotropin content. Without taking into account all the protein impurities, the beta subunit of LH was detected only in traces (0.9-1.2%) in all tested HP-HMG samples, confirming the data obtained by intact molecule analysis, while high levels of beta hCG (18-47%) were observed. Advanced molecular analysis of HP-hMG indicates a primarily placental origin of hCG, as evidenced by the absence of hCG sulfated glycans and the predominance of placental non-sulfated hCG in LH activity. The analysis revealed 20-30% of protein impurities and a significant presence of oxidized forms in the HP-hMG samples. These findings are critical for understanding the quality, safety, and clinical profile of HP-hMG.

Randomized Pharmacokinetic Study of a Highly Purified Human Chorionic Gonadotropin and of a Recombinant Human Chorionic Gonadotropin Following Single Subcutaneous Administration in Healthy Women

Background and Objectives

Exogenous human chorionic gonadotropin (hCG) acts on the final phase of the follicle maturation. Choriomon^®, a highly purified hCG formulation, is approved in many European and extra-European countries for the induction of ovulation after stimulation of follicular development. The present study compares hCG bioavailability of Choriomon^® (Test product) versus a recombinant hCG preparation (Ovitrelle^®; Reference product).

Methods

In this randomized, two-way cross-over study, 26 healthy women received a single dose of Choriomon^® (10,000 IU) and Ovitrelle^® (250 µg; 6500 IU) by subcutaneous injection. hCG was determined in serum up to 192 h post-dose. Dose-normalized peak concentration (C_max) and area under the concentration-time curve up to the time of the last quantifiable concentration (AUC_0–t) and extrapolated to infinity (AUC_0–∞) were calculated and compared between the two treatments.

Results

Serum hCG concentrations increased rapidly with a very similar pharmacokinetic curve for the two products. The test/reference geometric means ratio (GMR) for AUC_0–t and AUC_0–∞ corresponded to 121.31 and 119.81%, and the upper limits of the 90% confidence intervals (CIs) (130.21% and 128.51%, for AUC_0–t and AUC_0–∞, respectively) exceeded the 125% bioequivalence threshold. C_max GMR was 146.89%, indicating a rate of hCG absorption approximately 50% greater for the test product (90% CI 132.30–163.10). Half-life (t_1/2) was very similar (36.77 ± 5.11 h and 38.63 ± 6.08 h), whereas time to achieve C_max (t_max) significantly differed, with median values of 16 h and 24 h for Choriomon^® and Ovitrelle^®, respectively, (p = 0.0023).

Conclusions

The differences between Choriomon^® and Ovitrelle^® pharmacokinetic parameters can be ascribed to the different raw source of the products and are reflected in the approved dose regimens of the two hCG formulations. The observed lack of bioequivalence between the two compounds at the given doses is not clinically relevant, as results from Phase III studies indicated similar clinical efficacy and safety. The safety data are in line with the known safety profile of the two products.

Clinicaltrials.gov registration no

NCT03735030.

Long-acting microspheres of Human Chorionic Gonadotropin hormone: In-vitro and in-vivo evaluation

Human Chorionic Gonadotropin (hCG) hormone is used to cause ovulation, treat infertility in women, and increase sperm count in men. Conventional hCG solution formulations require multiple administration of hCG per week and cause patient noncompliance. The long-acting PLGA depot microspheres (MS) approach with hCG can improve patient compliance, increase the efficacy of hCG with a lower total dose and improve quality of life. Therefore, hCG was encapsulated by a modified double emulsion solvent evaporation technique within PLGA MS by high-speed homogenizer and industrially scalable in-line homogenizer, respectively. MS was characterized for particle size, encapsulation efficiency (EE), surface morphology, and in-vitro release. The spherical, dense, non-porous microspheres were obtained with a size of 58.88 ± 0.18 µm. Microspheres showed high EE (77.4% ± 5.9%) with low initial burst release (12.82% ± 2.07%). Circular Dichroism and SDS-PAGE analysis indicated good stability and structural integrity of hCG in the microspheres. Its bioactivity was proven further by a bioassay study in immature Wistar rats. Pharmacokinetic analysis showed that the hCG PLGA MS maintained serum hCG concentration up to 13 days compared to multiple injections of a marketed conventional parenteral injectable formulation of hCG. Thus, it can be ascertained that the hCG PLGA MS may have great potential for clinical use in long-term therapy.

Evaluation of the predictive performance of physiologically based pharmacokinetic models for intramuscular injections of therapeutic proteins

Several physiologically-based pharmacokinetic (PBPK) models have been reported for intravenous (IV) and subcutaneous (SC) injections, but there has been a paucity of work for intramuscular (IM) injections. The primary objective of this work was a wide-scale evaluation of the predictive performance of IM PBPK models of therapeutic proteins. PBPK models for all administration routes available in the literature have regarded muscle as the total muscle (TM) in the body; however, anatomically, the body is composed of discrete muscle groups. Clinically, IM is administered to a specific muscle (SM). We explored the predictive performance of IM PBPK models with an SM or TM dosing site. The plasma concentration-time profiles of seven therapeutic proteins after an IM dose in humans served as the clinically observed data for model evaluation - this was a diverse group ranging from 30 to 149 kDa from six protein classes. Pharmacokinetic parameters C_max, t_max, AUC_0-∞, and ka were estimated. SM and TM IM PBPK approaches were compared using Average Fold Error (AFE) and Pearson Chi-Square LineShape analyses. This work represents the first wide-scale validation of IM PBPK models and suggests that these models predict IM PBPK reasonably well. The SM and TM approach provided comparable performance.

Management Strategies for POSEIDON Groups 3 and 4

In the POSEIDON classification, patients belonging to groups 3 and 4 share the same common feature of a poor ovarian reserve which independently of age renders them at high risk of a poor reproductive outcome. Overall, POSEIDON groups 1-4 constitute approximately 47% of patients attending assisted reproductive technology (ART) treatment. With the increasing delay in childbearing, POSEIDON group 4 seems to increase in numbers now in some centers constituting more than 50% of the total POSEIDON population, whereas group 3 patients constitute approximately 10%. Both POSEIDON groups 3 and 4 patients require special attention as regards pre-treatment strategy, ovarian stimulation, adjuvant treatment, and ovulation trigger strategy in order to optimize the probability of having at least one euploid blastocyst for transfer. Although more evidence is needed, recent advances seem to have increased the reproductive outcomes in the poor prognosis patient. The key to success is individualization in all steps of ART treatment. Herein, we review the recent evidence for the management of POSEIDON groups 3 and 4.

GnRH agonist trigger with intensive luteal phase support vs. human chorionic gonadotropin trigger in high responders: an observational study reporting pregnancy outcomes and incidence of ovarian hyperstimulation syndrome

A retrospective, cohort study of high-risk patients undergoing IVF treatment was performed to assess if there is a difference in clinical pregnancy rate, live birth rate and the incidence of ovarian hyperstimulation syndrome, when a GnRH agonist (GnRHa) trigger with intensive luteal support is compared to human chorionic gonadotropin (hCG) with standard luteal support. The control group consisted of 382 high-risk patients having a GnRH antagonist protocol with 194 receiving an hCG trigger. All patients had ≥18 follicles ≥11mm or serum oestradiol >18,000pmol/l on the day of trigger. Patients had a single or double embryo transfer at cleavage or blastocyst stage. Logistic regression was used to adjust for differences between the groups. An intention-to-treat analysis of all cycles was performed. No statistically significant differences were observed in terms of positive pregnancy test, clinical pregnancy rate and live birth rate. Only one patient (0.3%) was hospitalized with severe OHSS in the GnRHa group, compared to 26 patients (13%) in the hCG group. In conclusion, GnRHa trigger is associated with similar pregnancy rates with hCG trigger and a significant reduction in hospitalization for severe OHSS after an intention to treat analysis was performed.

Early Short Stimulation Modified Natural Cycle IVF With GnRH Agonist Trigger and In Vitro Maturation in a Woman with Polycystic Ovary Syndrome: A Case Report

BACKGROUND

Gonadotropin-releasing hormone agonist (GnRHa) triggering of final oocyte maturation has been used successfully in GnRH antagonist IVF cycles. It has not been used to date in cycles in which immature oocytes are matured in vitro.

CASE

We report here for the first time that GnRHa triggering in a variation on the modified natural IVF cycle can be used as a strategy in the treatment of infertility secondary to polycystic ovary syndrome. In this approach, follicles were stimulated with gonadotropins for three to five days when they were small, and triggering of ovulation occurred when the largest follicles were 10 to 12 mm in diameter. This was followed by retrieval of many immature oocytes that were matured in vitro and subsequently developed to form blastocysts that resulted in a live birth.

CONCLUSION

This is the first human evidence that GnRHa triggering of ovulation can be used successfully when the aim is in vitro maturation of oocytes.

Luteal phase support for assisted reproduction cycles

BACKGROUND

Progesterone prepares the endometrium for pregnancy by stimulating proliferation in response to human chorionic gonadotropin(hCG) produced by the corpus luteum. This occurs in the luteal phase of the menstrual cycle. In assisted reproduction techniques(ART), progesterone and/or hCG levels are low, so the luteal phase is supported with progesterone, hCG or gonadotropin-releasing hormone (GnRH) agonists to improve implantation and pregnancy rates.

OBJECTIVES

To determine the relative effectiveness and safety of methods of luteal phase support provided to subfertile women undergoing assisted reproduction.

SEARCH METHODS

We searched databases including the Cochrane Menstrual Disorders and Subfertility Group (MDSG) Specialised Register, the Cochrane Central Register of Controlled Trials (CENTRAL), MEDLINE, EMBASE, PsycINFO and trial registers. We conducted searches in November 2014, and further searches on 4 August 2015.

SELECTION CRITERIA

Randomised controlled trials (RCTs) of luteal phase support using progesterone, hCG or GnRH agonist supplementation in ART cycles.

DATA COLLECTION AND ANALYSIS

Three review authors independently selected trials, extracted data and assessed risk of bias. We calculated odds ratios (ORs) and 95%confidence intervals (CIs) for each comparison and combined data when appropriate using a fixed-effect model. Our primary out come was live birth or ongoing pregnancy. The overall quality of the evidence was assessed using GRADE methods.

MAIN RESULTS

Ninety-four women RCTs (26,198 women) were included. Most studies had unclear or high risk of bias in most domains. The main limitations in the evidence were poor reporting of study methods and imprecision due to small sample sizes.1. hCG vs placebo/no treatment (five RCTs, 746 women)There was no evidence of differences between groups in live birth or ongoing pregnancy (OR 1.67, 95% CI 0.90 to 3.12, three RCTs,527 women, I2 = 24%, very low-quality evidence, but I2 of 61% was found for the subgroup of ongoing pregnancy) with a random effects model. hCG increased the risk of ovarian hyperstimulation syndrome (OHSS) (1 RCT, OR 4.28, 95% CI 1.91 to 9.6, low quality evidence).2. Progesterone vs placebo/no treatment (eight RCTs, 875 women)Evidence suggests a higher rate of live birth or ongoing pregnancy in the progesterone group (OR 1.77, 95% CI 1.09 to 2.86, five RCTs, 642 women, I2 = 35%, very low-quality evidence). OHSS was not reported.3. Progesterone vs hCG regimens (16 RCTs, 2162 women)hCG regimens included comparisons of progesterone versus hCG and progesterone versus progesterone + hCG. No evidence showed differences between groups in live birth or ongoing pregnancy (OR 0.95, 95% CI 0.65 to 1.38, five RCTs, 833 women, I2 = 0%, low quality evidence) or in the risk of OHSS (four RCTs, 615 women, progesterone vs hCG OR 0.54, 95% CI 0.22 to 1.34; four RCTs,678 women; progesterone vs progesterone plus hCG, OR 0.34, 95% CI 0.09 to 1.26, low-quality evidence).4. Progesterone vs progesterone with oestrogen (16 RCTs, 2577 women)No evidence was found of differences between groups in live birth or ongoing pregnancy (OR 1.12, 95% CI 0.91 to 1.38, nine RCTs,1651 women, I2 = 0%, low-quality evidence) or OHSS (OR 0.56, 95% CI 0.2 to 1.63, two RCTs, 461 women, I2 = 0%, low-quality evidence).5. Progesterone vs progesterone + GnRH agonist (seven RCTs, 1708 women)Live birth or ongoing pregnancy rates were lower in the progesterone-only group and increased in women who received progester one and one or more GnRH agonist doses (OR 0.62, 95% CI 0.48 to 0.81, nine RCTs, 2861 women, I2 = 55%, random effects, low quality evidence). Statistical heterogeneity for this comparison was high because of unexplained variation in the effect size, but the direction of effect was consistent across studies. OHSS was reported in one study only (OR 1.00, 95% CI 0.33 to 3.01, 1 RCT, 300 women, very low quality evidence).6. Progesterone regimens (45 RCTs, 13,814 women)The included studies reported nine different comparisons between progesterone regimens. Findings for live birth or ongoing pregnancy were as follows: intramuscular (IM) versus oral: OR 0.71, 95% CI 0.14 to 3.66 (one RCT, 40 women, very low-quality evidence);IM versus vaginal/rectal: OR 1.24, 95% CI 1.03 to 1.5 (seven RCTs, 2309 women, I2 = 71%, very low-quality evidence); vaginal/rectal versus oral: OR 1.19, 95% CI 0.83 to 1.69 (four RCTs, 857 women, I2 = 32%, low-quality evidence); low-dose versus high-dose vaginal: OR 0.97, 95% CI 0.84 to 1.11 (five RCTs, 3720 women, I2 = 0%, moderate-quality evidence); short versus long protocol:OR 1.04, 95% CI 0.79 to 1.36 (five RCTs, 1205 women, I2 = 0%, low-quality evidence); micronised versus synthetic: OR 0.9, 95%CI 0.53 to 1.55 (two RCTs, 470 women, I2 = 0%, low-quality evidence); vaginal ring versus gel: OR 1.09, 95% CI 0.88 to 1.36 (oneRCT, 1271 women, low-quality evidence); subcutaneous versus vaginal gel: OR 0.92, 95% CI 0.74 to 1.14 (two RCTs, 1465 women,I2 = 0%, low-quality evidence); and vaginal versus rectal: OR 1.28, 95% CI 0.64 to 2.54 (one RCT, 147 women, very low-quality evidence). OHSS rates were reported for only two of these comparisons: IM versus oral, and low versus high-dose vaginal. No evidence showed a difference between groups.7. Progesterone and oestrogen regimens (two RCTs, 1195 women)The included studies compared two different oestrogen protocols. No evidence was found to suggest differences in live birth or ongoing pregnancy rates between a short and a long protocol (OR 1.08, 95% CI 0.81 to 1.43, one RCT, 910 women, low-quality evidence) or between a low dose and a high dose of oestrogen (OR 0.65, 95% CI 0.37 to 1.13, one RCT, 285 women, very low-quality evidence).Neither study reported OHSS.

AUTHORS' CONCLUSIONS

Both progesterone and hCG during the luteal phase are associated with higher rates of live birth or ongoing pregnancy than placebo.The addition of GnRHa to progesterone is associated with an improvement in pregnancy outcomes. OHSS rates are increased with hCG compared to placebo (only study only). The addition of oestrogen does not seem to improve outcomes. The route of progester one administration is not associated with an improvement in outcomes.

Pharmacokinetics and Safety Profile of DA-3803, a Proposed Biosimilar of Recombinant Human Chorionic Gonadotropin, in Healthy Subjects

BACKGROUND AND OBJECTIVE

DA-3803 is a proposed biosimilar of recombinant human chorionic gonadotropin (r-hCG), which is a therapeutic protein used to treat infertility. We compared the pharmacokinetics and safety profiles of DA-3803 (test) with those of a conventional formulation (Ovidrel(®), reference).

METHODS

A single-blind, randomized, single-dose, two-period, two-sequence, crossover study was conducted in 32 healthy subjects. In each period, 250 μg of r-hCG of the test or reference formulation was administered subcutaneously with a 3-week washout period. Serial blood samples were obtained for pharmacokinetic analysis and blood levels of human chorionic gonadotropin (hCG) were determined. The geometric mean ratios (GMRs) with 90 % confidence intervals (CIs) for the maximum (peak) plasma concentration (C max) and the area under the plasma concentration-time curve (AUC) were estimated.

RESULTS

Among the 32 subjects, 27 completed the study. No serious adverse events were observed. The mean concentration-time profiles of the test formulation tended to be higher than those of the reference formulation. The mean C max values of the two products were similar (142 mIU/mL for reference vs. 143 mIU/mL for test), but the mean AUC from time zero to infinity (AUC∞) values of the test drug were approximately 25 % higher than those of the reference drug (9403 mIU·h/mL for reference vs. 11,817 mIU·h/mL for test). The GMR (90 % CI) of the test formulation to the reference formulation for C max, AUC from time zero to the last measurable time (AUClast), and AUC∞ were 1.03 (0.93-1.14), 1.25 (1.18-1.33), and 1.27 (1.19-1.35), respectively.

CONCLUSION

A single subcutaneous injection of either DA-3803 or Ovidrel(®) was safe and well-tolerated. A comparative pharmacokinetics study showed that DA-3803 was bioequivalent to Ovidrel(®) in the C max value but non-equivalent in the AUC value. These pharmacokinetic differences may not be expected to affect therapeutic efficacy of these two drugs, but further clinical studies are warranted to confirm their therapeutic equivalence.

A review of luteinising hormone and human chorionic gonadotropin when used in assisted reproductive technology

Gonadotropins extracted from the urine of post-menopausal women have traditionally been used to stimulate folliculogenesis in the treatment of infertility and in assisted reproductive technology (ART). Products, such as human menopausal gonadotropin (hMG), consist not only of a mixture of the hormones, follicle-stimulating hormone (FSH), luteinising hormone (LH) and human chorionic gonadotropin (hCG), but also other biologically active contaminants, such as growth factors, binding proteins and prion proteins. The actual amount of molecular LH in hMG preparations varies considerably due to the purification process, thus hCG, mimicking LH action, is added to standardise the product. However, unlike LH, hCG plays a different role during the natural human menstrual cycle. It is secreted by the embryo and placenta, and its main role is to support implantation and pregnancy. More recently, recombinant gonadotropins (r-hFSH and r-hLH) have become available for ART therapies. Recombinant LH contains only LH molecules. In the field of reproduction there has been controversy in recent years over whether r-hLH or hCG should be used for ART. This review examines the existing evidence for molecular and functional differences between LH and hCG and assesses the clinical implications of hCG-supplemented urinary therapy compared with recombinant therapies used for ART.

Pharmacokinetics of human chorionic gonadotropin injection in obese and normal-weight women

CONTEXT

Obese women have poorer in vitro fertilization outcomes, but underlying mechanisms remain unclear.

OBJECTIVE

The objectives of the study were to compare the pharmacokinetics of human chorionic gonadotropin (hCG) and ovarian steroid hormone production, after subcutaneous (s.c.) and intramuscular (i.m.) injection of hCG in obese and normal-weight women.

DESIGN AND SETTING

This was a randomized, experimental study.

PATIENTS OR OTHER PARTICIPANTS

Twenty-two women aged 18-42 years with body mass index of 18.5-24.9 (normal) or 30-40 kg/m(2) (obese).

INTERVENTIONS

Participants received im urinary hCG or s.c. recombinant hCG and returned for a second injection type after a 4-week washout. Intramuscular injections were performed under ultrasound guidance. Blood was taken 0, 0.5, 1, 2, 4, 6, 8, 12, 24, and 36 hours after injection.

MAIN OUTCOME MEASURES

hCG was measured at each time point; estradiol, progesterone, 17-hydroxyprogesterone (17-OHP), testosterone (T), dehydroepiandrosterone, and SHBG were measured at 0 and 36 hours.

RESULTS

Twenty-two women completed the study. In both normal-weight and obese women, peak serum concentration (Cmax), area under the curve (AUC), and average hCG concentration were higher after i.m. injection as compared with s.c. injection (all P < .003). Obese women had markedly lower Cmax, AUC, and average hCG concentration after s.c. injection as compared with normal-weight women (P = .02, P = .009, and P = .008, respectively). After i.m. injection, Cmax, AUC, and average concentration were similar for normal-weight and obese women (P = .31, P = .25, and P = .18, respectively). Thirty-six percent of obese women had muscular layers beyond the reach of a standard 1.5 inch needle. hCG caused a significant rise in 17-OHP in both obese and normal-weight women and an increase in T in obese but not normal-weight women (all P < .04).

CONCLUSIONS

Subcutaneous injection yields lower hCG levels in obese women. Standard-length needles are insufficient to administer i.m. injections in many obese women.

Impact of physiochemical properties on pharmacokinetics of protein therapeutics

Physicochemical properties, such as molecular weight, size, partition coefficient, acid dissociation constant and solubility have a great impact on pharmacokinetics of traditional small molecule drugs and substantially used in development of small drugs. However, predicting pharmacokinetic fate (absorption, distribution, metabolism and elimination) of protein therapeutics from their physicochemical parameters is extremely difficult due to the macromolecular nature of therapeutic proteins and peptides. Their structural complexity and immunogenicity are other contributing factors that determine their biological fate. Therefore, to develop generalized strategies concerning development of therapeutic proteins and peptides are highly challenging. However, reviewing the literature, authors found that physiochemical properties, such as molecular weight, charge and structural modification are having great impact on pharmacokinetics of protein therapeutics and an attempt is made to provide the major findings in this manuscript. This manuscript will serve to provide some bases for developing protein therapeutics with desired pharmacokinetic profile.

Endometrial gene expression in the early luteal phase is impacted by mode of triggering final oocyte maturation in recFSH stimulated and GnRH antagonist co-treated IVF cycles

STUDY QUESTION

Do differences in endometrial gene expression exist after ovarian stimulation with four different regimens of triggering final oocyte maturation and luteal phase support in the same patient?

SUMMARY ANSWER

Significant differences in the expression of genes involved in receptivity and early implantation were seen between the four protocols.

WHAT IS KNOWN ALREADY

GnRH agonist triggering is an alternative to hCG triggering in GnRH antagonist co-treated cycles, resulting in an elimination of early ovarian hyperstimulation syndrome. Whereas previous studies have revealed a low ongoing clinical pregnancy rate after GnRH agonist trigger due to a high early pregnancy loss rate, despite supplementation with the standard luteal phase support, more recent studies, employing a 'modified' luteal phase support including a bolus of 1500 IU hCG on the day of oocyte aspiration, have reported ongoing pregnancy rates similar to those seen after hCG triggering.

STUDY DESIGN, SIZE DURATION

A prospective randomized study was performed in four oocyte donors recruited from an oocyte donation program during the period 2010-2011.

PARTICIPANTS, MATERIALS, SETTING, METHODS

Four oocyte donors in a university IVF center each prospectively underwent four consecutive stimulation protocols, with different modes of triggering final oocyte maturation and a different luteal phase support, followed by endometrial biopsy on Day 5 after oocyte retrieval. The following protocols were used: (A) 10 000 IU hCG and standard luteal phase support, (B) GnRH agonist (triptorelin 0.2 mg), followed by 1500 IU hCG 35 h after triggering final oocyte maturation, and standard luteal phase support, (C) GnRH agonist (triptorelin 0.2 mg) and standard luteal phase support and (D) GnRH agonist (triptorelin 0.2 mg) without luteal phase support. Microarray data analysis was performed with GeneSpring GX 11.5 (RMA algorithm). Pathway and network analysis was performed with the gene ontology software Ingenuity Pathways Analysis (Ingenuity® Systems, www.ingenuity.com, Redwood City, CA, USA). Samples were grouped and background intensity values were removed (cutoff at the lowest 20th percentile). A one-way ANOVA test (P< 0.05) was performed with Benjamini-Hochberg multiple testing correction.

MAIN RESULTS

Significant differences were seen in endometrial gene expression, related to the type of ovulation trigger and luteal phase support. However, the endometrial gene expression after the GnRH agonist trigger and a modified luteal phase support (B) was similar to the pattern seen after the hCG trigger (A).

LIMITATIONS, REASONS FOR CAUTION

The study was performed in four oocyte donors only; however, it is a strength of the study that the same donor underwent four consecutive stimulation protocols within 1 year to avoid inter-individual variations.

WIDER IMPLICATIONS OF THE FINDINGS

These endometrial gene-expression findings support the clinical reports of a non-significant difference in live birth rates between the GnRH agonist trigger and the hCG trigger, when the GnRH agonist trigger is followed by a bolus of 1500 IU hCG at 35 h post trigger in addition to the standard luteal phase support.

STUDY FUNDING/ COMPETING INTERESTS

This study was supported by an un-restricted research grant by MSD Belgium.

TRIAL REGISTRATION NUMBER

EudraCT number 2009-009429-26, protocol number 997 (P06034).

Pharmacokinetics and toxicology of therapeutic proteins: Advances and challenges

Significant progress has been made in understanding pharmacokinetics (PK), pharmacodynamics (PD), as well as toxicity profiles of therapeutic proteins in animals and humans, which have been in commercial development for more than three decades. However, in the PK arena, many fundamental questions remain to be resolved. Investigative and bioanalytical tools need to be established to improve the translation of PK data from animals to humans, and from in vitro assays to in vivo readouts, which would ultimately lead to a higher success rate in drug development. In toxicology, it is known, in general, what studies are needed to safely develop therapeutic proteins, and what studies do not provide relevant information. One of the major complicating factors in nonclinical and clinical programs for therapeutic proteins is the impact of immunogenicity. In this review, we will highlight the emerging science and technology, as well as the challenges around the pharmacokinetic- and safety-related issues in drug development of mAbs and other therapeutic proteins.

The use of recombinant luteinizing hormone in patients undergoing assisted reproductive techniques with advanced reproductive age: a systematic review and meta-analysis

OBJECTIVE

To evaluate the effect of recombinant LH in assisted reproduction technology (ART) cycles in patients of advanced reproductive age.

DESIGN

A systematic review and meta-analysis.

SETTING

Published randomized controlled clinical trials comparing recombinant LH plus recombinant FSH versus recombinant FSH only in patients of advanced reproductive age.

PATIENT(S)

Patients 35 years and older undergoing assisted reproduction.

INTERVENTION(S)

Recombinant LH plus recombinant FSH controlled ovarian hyperstimulation (COH) versus recombinant FSH stimulation only in assisted reproduction cycles.

MAIN OUTCOME MEASURE(S)

Implantation and clinical pregnancy.

RESULT(S)

Seven trials were identified that met inclusion criteria and comprised 902 assisted reproduction technology cycles. No differences in serum E(2) on the day of hCG administration were reported in any trials. Two trials reported lower oocyte yield and one trial reported lower metaphase II oocyte yield in the recombinant LH-supplemented group. One trial reported higher fertilization rates in the recombinant LH-supplemented group. In a fixed effect model, implantation was higher in the recombinant LH-supplemented group (odds ratio 1.36, 95% confidence interval 1.05-1.78). Similarly, clinical pregnancy was increased in the recombinant LH-supplemented group (odds ratio 1.37, 95% confidence interval 1.03-1.83).

CONCLUSION(S)

The addition of recombinant LH to ART cycles may improve implantation and clinical pregnancy in patients of advanced reproductive age.

Prevention of the onset of ovarian hyperstimulation syndrome (OHSS) in the rat after ovulation induction with a low molecular weight agonist of the LH receptor compared with hCG and rec-LH

Ovarian hyperstimulation syndrome (OHSS) incidentally occurs in controlled ovarian stimulation protocols and is associated with human chorionic gonadotropin (hCG) administration. OHSS is caused by increased vascular permeability (VP) and thought to be mediated by hypersecretion of vascular endothelial growth factor (VEGF) by granulosa cells. Low molecular weight (LMW)-LH agonists have a similar mode of action but a shorter half-life compared with hCG, which could potentially lead to a clinical benefit in reducing the risk for OHSS in controlled ovarian stimulation protocols. The objective of this study is to investigate the role of an orally active LMW-LH agonist in OHSS induction compared with recombinant LH (rec-LH) and hCG. Immature rats were hyperstimulated with pregnant mare serum gonadotropin, and ovulation was induced by hCG, rec-LH or a LMW-LH agonist. The degree of VP was determined by Evans Blue in the abdominal cavity. Ovaries were weighed, and VEGF concentration in the ovary was determined. Pregnant mare serum gonadotropin stimulation followed by single-dose hCG or rec-LH resulted in clear enlargement of the ovaries and increased VP and VEGF levels. However, ovulation induction with a single dose of the LMW-LH agonist did not result in increased VP and VEGF levels, and even multiple dosing to mimic a longer exposure did not induce OHSS symptoms. In conclusion, we demonstrated that the oral LMW-LH agonist did not induce VP in rat, indicative for OHSS, possibly due to reduced VEGF production. If this is translatable to human, this could potentially represent a clinical benefit in reducing the risk for OHSS when using these compounds in controlled ovarian stimulation protocols.

Luteal phase support for assisted reproduction cycles

BACKGROUND

Progesterone prepares the endometrium for pregnancy by stimulating proliferation in response to human chorionic gonadotropin (hCG), which is produced by the corpus luteum. This occurs in the luteal phase of the menstrual cycle. In assisted reproduction techniques (ART) the progesterone or hCG levels, or both, are low and the natural process is insufficient, so the luteal phase is supported with either progesterone, hCG or gonadotropin releasing hormone (GnRH) agonists. Luteal phase support improves implantation rate and thus pregnancy rates but the ideal method is still unclear. This is an update of a Cochrane Review published in 2004 (Daya 2004).

OBJECTIVES

To determine the relative effectiveness and safety of methods of luteal phase support in subfertile women undergoing assisted reproductive technology.

SEARCH STRATEGY

We searched the Cochrane Menstrual Disorders and Subfertility Group (MDSG) Specialised Register, Cochrane Central Register of Controlled Trials (CENTRAL), MEDLINE, EMBASE, PsycINFO, CINAHL, Database of Abstracts of Reviews of Effects (DARE), LILACS, conference abstracts on the ISI Web of Knowledge, OpenSigle for grey literature from Europe, and ongoing clinical trials registered online. The final search was in February 2011.

SELECTION CRITERIA

Randomised controlled trials of luteal phase support in ART investigating progesterone, hCG or GnRH agonist supplementation in in vitro fertilisation (IVF) or intracytoplasmic sperm injection (ICSI) cycles. Quasi-randomised trials and trials using frozen transfers or donor oocyte cycles were excluded.

DATA COLLECTION AND ANALYSIS

We extracted data per women and three review authors independently assessed risk of bias. We contacted the original authors when data were missing or the risk of bias was unclear. We entered all data in six different comparisons. We calculated the Peto odds ratio (Peto OR) for each comparison.

MAIN RESULTS

Sixty-nine studies with a total of 16,327 women were included. We assessed most of the studies as having an unclear risk of bias, which we interpreted as a high risk of bias. Because of the great number of different comparisons, the average number of included studies in a single comparison was only 1.5 for live birth and 6.1 for clinical pregnancy.Five studies (746 women) compared hCG versus placebo or no treatment. There was no evidence of a difference between hCG and placebo or no treatment except for ongoing pregnancy: Peto OR 1.75 (95% CI 1.09 to 2.81), suggesting a benefit from hCG. There was a significantly higher risk of ovarian hyperstimulation syndrome (OHSS) when hCG was used (Peto OR 3.62, 95% CI 1.85 to 7.06).There were eight studies (875 women) in the second comparison, progesterone versus placebo or no treatment. The results suggested a significant effect in favour of progesterone for the live birth rate (Peto OR 2.95, 95% CI 1.02 to 8.56) based on one study. For clinical pregnancy (CPR) the results also suggested a significant result in favour of progesterone (Peto OR 1.83, 95% CI 1.29 to 2.61) based on seven studies. For the other outcomes the results indicated no difference in effect.The third comparison (15 studies, 2117 women) investigated progesterone versus hCG regimens. The hCG regimens were subgrouped into comparisons of progesterone versus hCG and progesterone versus progesterone + hCG. The results did not indicate a difference of effect between the interventions, except for OHSS. Subgroup analysis of progesterone versus progesterone + hCG showed a significant benefit from progesterone (Peto OR 0.45, 95% CI 0.26 to 0.79).The fourth comparison (nine studies, 1571 women) compared progesterone versus progesterone + oestrogen. Outcomes were subgrouped by route of administration. The results for clinical pregnancy rate in the subgroup progesterone versus progesterone + transdermal oestrogen suggested a significant benefit from progesterone + oestrogen. There was no evidence of a difference in effect for other outcomes.Six studies (1646 women) investigated progesterone versus progesterone + GnRH agonist. We subgrouped the studies for single-dose GnRH agonist and multiple-dose GnRH agonist. For the live birth, clinical pregnancy and ongoing pregnancy rate the results suggested a significant effect in favour of progesterone + GnRH agonist. The Peto OR for the live birth rate was 2.44 (95% CI 1.62 to 3.67), for the clinical pregnancy rate was 1.36 (95% CI 1.11 to 1.66) and for the ongoing pregnancy rate was 1.31 (95% CI 1.03 to 1.67). The results for miscarriage and multiple pregnancy did not indicate a difference of effect.The last comparison (32 studies, 9839 women) investigated different progesterone regimens:intramuscular (IM) versus oral administration, IM versus vaginal or rectal administration, vaginal or rectal versus oral administration, low-dose vaginal versus high-dose vaginal progesterone administration, short protocol versus long protocol and micronized progesterone versus synthetic progesterone. The main results of this comparison did not indicate a difference of effect except in some subgroup analyses. For the outcome clinical pregnancy, subgroup analysis of micronized progesterone versus synthetic progesterone showed a significant benefit from synthetic progesterone (Peto OR 0.79, 95% CI 0.65 to 0.96). For the outcome multiple pregnancy, the subgroup analysis of IM progesterone versus oral progesterone suggested a significant benefit from oral progesterone (Peto OR 4.39, 95% CI 1.28 to 15.01).

AUTHORS' CONCLUSIONS

This review showed a significant effect in favour of progesterone for luteal phase support, favouring synthetic progesterone over micronized progesterone. Overall, the addition of other substances such as estrogen or hCG did not seem to improve outcomes. We also found no evidence favouring a specific route or duration of administration of progesterone. We found that hCG, or hCG plus progesterone, was associated with a higher risk of OHSS. The use of hCG should therefore be avoided. There were significant results showing a benefit from addition of GnRH agonist to progesterone for the outcomes of live birth, clinical pregnancy and ongoing pregnancy. For now, progesterone seems to be the best option as luteal phase support, with better pregnancy results when synthetic progesterone is used.

Low-dose human chorionic gonadotropin may improve in vitro fertilization cycle outcomes in patients with low luteinizing hormone levels after gonadotropin-releasing hormone antagonist administration

OBJECTIVE

To evaluate the effect of low levels of endogenous luteinizing hormone (LH) and low-dose human chorionic gonadotropin (hCG) supplementation on in vitro fertilization (IVF) cycle outcomes in a gonadotropin-releasing hormone (GnRH) antagonist protocol.

DESIGN

Retrospective study.

SETTING

Military medical center.

PATIENT(S)

General in vitro fertilization/embryo transfer (IVF-ET) population.

INTERVENTION(S)

Addition of low-dose urinary hCG to IVF stimulations using a recombinant follicle-stimulating hormone (FSH) and GnRH antagonist protocol.

MAIN OUTCOME MEASURE(S)

Implantation and live-birth rates.

RESULT(S)

As part of a larger cohort of 239 patients, 42 patients with LH levels ≤ 0.5 mIU/mL were evaluated. In the larger cohort, there were no differences in implantation and pregnancy rates between the recombinant FSH only (n = 113) and the recombinant FSH with low-dose hCG supplementation (n = 126) groups. In the FSH-only group, patients with LH levels ≤ 0.5 mIU/mL had decreased implantation rates (19% vs. 42%) and live-birth rates (25% vs. 54%) as compared with patients with LH levels >0.5 mIU/mL. Low LH patients in the recombinant FSH with low-dose urinary hCG group had statistically significantly higher implantation rates (54% vs. 19%) and live-birth rates (64% vs. 25%) as compared with patients with similar low LH levels in the recombinant FSH-only group.

CONCLUSION(S)

Endogenous LH levels ≤ 0.5 mIU/mL after GnRH antagonist treatment are associated with statistically significantly lower implantation and pregnancy rates in recombinant FSH-only cycles. The addition of low-dose urinary hCG results in improved implantation and live-birth rates in patients with low LH levels.

Influence of body mass index and self-administration of hCG on the outcome of IVF cycles: a prospective cohort study

Final maturation of the oocyte in in vitro fertilization (IVF) cycles is achieved through the administration of a timed injection of human chorionic gonadotrophin (hCG). The success of mature oocyte retrieval is dependent on serum concentrations of the hormone reaching values capable of initiating meiosis and triggering the release of the cumulus-oocyte complex into the follicular fluid. The objective of this prospective cohort study was to examine the effect of adiposity, as measured by body mass index (BMI), on serum concentrations of hCG and gonadotrophins and to relate this to IVF outcome. A comparison was also made between professionally and non-professionally administered hCG to assess any possible effect on cycle parameters. A total of 50 patients with a high BMI (> or = 26 kg m(-2)) who underwent IVF treatment at the Assisted Conception Unit, St James's University Hospital, Leeds, was recruited prospectively into the study. They were matched with 50 patients with a normal BMI (18-25 kg m(-2)) who acted as a control group. The two groups were matched for age (mean of 32 years and range of 22-42 years) and cause of infertility. Serum gonadotrophins, oestradiol and hCG concentrations, measured at the time of oocyte retrieval, and the clinical outcome of the two groups were compared. Patients with a high BMI had a significantly lower mean serum hCG concentration compared with controls (63.9 versus 99.6 iu l(-1), P < 0.0003). They also required a higher dosage of gonadotrophin (3660 versus 3007 iu) to achieve follicular maturation than the controls. Similarly, the high BMI group of patients had higher serum concentrations of follicle-stimulating hormone (FSH) (12.3 versus 11.2 iu l(-1)) and lower oestradiol (3499 versus 3506 pmol l(-1)) compared with controls. Patients with a high BMI had significantly fewer oocytes aspirated, resulting in a significant decrease in the oocyte:follicle ratio compared with controls (33.9 versus 41.7, P < 0.05). The fertilization rate (46.2 versus 61.3%, P < 0.05) and clinical pregnancy rate per cycle (26.6 versus 37.1%, P < 0.05) were also lower in the patients with high BMI compared with those with normal BMI. The administration of hCG by the patient or her partner did not have a significant effect on clinical outcome. The mean serum hCG at the time of oocyte recovery was equivalent in both groups (87.1 versus 89.7 iu l(-1)). Furthermore, the oocyte:follicle ratio (0.73 versus 0.72), fertilization rate (46.2 versus 54.2%) and clinical pregnancy rate (38.9 versus 36.5%) were similar. These findings indicate that high BMI is detrimental to the success of IVF treatment and has an important influence on the distribution and metabolism of hCG. The results also indicate that non-professional administration of hCG does not compromise cycle outcome.

Low-dose human chorionic gonadotropin during the proliferative phase may adversely affect endometrial receptivity in oocyte recipients

The effect of low-dose human chorionic gonadotropin (hCG) administration in the proliferative phase of oocyte recipients was investigated in a prospective randomized trial. Sibling oocytes from the same donor were shared at random among two different recipients. In group I oocyte recipients received 750 IU of hCG every three days concomitant to endometrial preparation with estradiol until hCG injection to the donor, whereas in group II recipients received no hCG during endometrial priming with estradiol. Endometrial thickness was significantly lower in group I compared with group II, although similar endometrial thickness was detected during the mock cycle. Pregnancy rates were significantly lower in group I than in group II (13.6% vs. 45.4%, p<0.05). Implantation rates were also significantly lower in group I (1.7% vs. 22.4%, p<0.01). The study was discontinued prematurely for ethical reasons when 22 cycles were completed, as pregnancy rates were very low in group I. In conclusion, hCG administration in the proliferative phase might directly affect endometrial proliferation and receptivity.

GnRH analogues: applications in assisted reproductive techniques

The ability to prevent an endogenous LH surge revolutionised the efficacy of assisted reproductive techniques (ART) such that GnRH agonists were rapidly adopted in the 1980s. Prior to this, premature luteinisation occurred in up to 25% of superovulated cycles leading to cycle cancellation and severely compromised outcomes. Analogues have been applied in a variety of drug protocols (long, short flare) but there has been little research to moderate the degree of pituitary suppression. There has also been ongoing and unresolved debate about the role of LH in supporting follicular development. By 2001, the first GnRH antagonists were registered for use in ART. Their ability to cause immediate suppression of gonadotrophin (particularly LH) secretion means that they can be given after exogenous stimulation has begun and thereby dramatically shorten the total duration of a treatment cycle. After initial enthusiasm and then scepticism that pregnancy rates may not be as high as the established agonist regimens, these preparations are now being increasingly adopted with at least comparable outcomes in large trials. They are certainly favoured by patients for their reduced side-effect profile and particularly for the shortening of the total cycle length. This shift in practice is occurring alongside gathering momentum in favour of milder stimulation protocols and a new perception of what constitutes successful treatment. The focus is moving away from surrogate outcomes such as oocyte numbers and conception rates towards long-term outcomes for women and their offspring, namely the achievement of a live singleton birth per treatment started.

Androgen priming using aromatase inhibitor and hCG during early-follicular-phase GnRH antagonist down-regulation in modified antagonist protocols

BACKGROUND

Temporary exposure of follicles to increased levels of androgens may enhance their sensitivity to FSH. The aim of this study was to increase the intraovarian androgen level using aromatase inhibitors and hCG before controlled ovarian stimulation (COH) and to test this concept clinically.

METHODS

In a prospective, non-randomized study, 45 patients were treated in modified antagonist protocols including early-follicular-phase down-regulation and androgen priming before COH. All patients received cetrorelix, 3 mg s.c., on cycle days 2 and 5. Group I (n=15) received no other pretreatment. Group II (n=15) received 1 daily tablet of aromatase inhibitor, letrozole 2.5 mg, from cycle days 2 to 8. Group III (n=15) received letrozole as Group II and 1250 IU of hCG s.c. on cycle day 2. From cycle day 8, all patients were stimulated with highly purified menotrophin in a flexible antagonist protocol.

RESULTS

Aromatase inhibitor increased the level of testosterone in follicular fluid (P<0.002), but not in plasma. Androgen priming with aromatase inhibitor and hCG increased the number of good-quality embryos (P=0.015) but did not increase the implantation rate.

CONCLUSIONS

The use of aromatase inhibitor before COH significantly influences the local endocrine environment before and during stimulation. Androgen priming with both aromatase inhibitor and hCG may result in more good-quality embryos.

Biochemical pregnancy after fertilization of an oocyte aspirated from a heterotopic autotransplant of cryopreserved ovarian tissue: Case Report

Autotransplantation of frozen/thawed ovarian tissue in women undergoing cancer therapy has so far led to the birth of two healthy babies. In both cases, it can be discussed whether the fertilized oocyte originated from the transplant or from the native ovary. We now present a biochemical pregnancy achieved after heterotopical autotransplantation of cryopreserved ovarian cortical tissue and hence the unquestionable proof that pregnancy can occur after transplantation of cryopreserved ovarian tissue. A woman diagnosed with Hodgkin's lymphoma had ovarian tissue cryopreserved at the age of 28, before receiving chemotherapy and radiation therapy that rendered her amenorrhoeic. After complete remission, she had autotransplantation of ovarian tissue to the remaining ovary, to the right pelvic wall and to a midline subperitoneal pocket on the lower abdominal wall. The transplanted tissue resumed hormone secretion and follicles developed in all three locations. Three times during 8 months, when follicles could not be visualized in other locations, oocytes were aspirated from the subperitoneal autotransplanted tissue on the lower abdominal wall. Twice, an oocyte was retrieved, fertilized by intracytoplasmatic sperm injection (ICSI) and transferred to the woman's uterus. One of the treatments resulted in a positive pregnancy test 14 days after transfer. Clinical pregnancy, however, was not achieved. In conclusion, heterotopic autotransplantation of cryopreserved ovarian tissue can sustain follicle development. The oocytes of aspirated mature follicles are capable of fertilization after ICSI, and the resulting embryo is competent of producing hCG at detectable levels.

The science behind 25 years of ovarian stimulation for in vitro fertilization

To allow selection of embryos for transfer after in vitro fertilization, ovarian stimulation is usually carried out with exogenous gonadotropins. To compensate for changes induced by stimulation, GnRH analog cotreatment, oral contraceptive pretreatment, late follicular phase human chorionic gonadotropin, and luteal phase progesterone supplementation are usually added. These approaches render ovarian stimulation complex and costly. The stimulation of multiple follicular development disrupts the physiology of follicular development, with consequences for the oocyte, embryo, and endometrium. In recent years, recombinant gonadotropin preparations have become available, and novel stimulation protocols with less detrimental effects have been developed. In this article, the scientific background to current approaches to ovarian stimulation for in vitro fertilization is reviewed. After a brief discussion of the relevant aspect of ovarian physiology, the development, application, and consequences of ovarian stimulation strategies are reviewed in detail.

Optimizing hCG cut-off values: a single determination on day 14 or 15 is sufficient for a reliable prediction of pregnancy outcome

OBJECTIVE

Optimizing the cut-off level for a single serum hCG determination around day 15 after oocyte retrieval or ovulation.

STUDY DESIGN

Retrospective data analysis.

RESULTS

204 hCG samples >5 IU/L between March and October 1999 taken on day 14, 15 or 16 after oocyte retrieval in 204 patients undergoing IVF or ICSI were analyzed. ROC-curves and optimal cut-off levels to discriminate between viable and non-viable pregnancies were calculated for each day separately. Cut-off levels were found at 76, 142 and 223 IU/L for day 14, 15 and 16, respectively, and were verified by 487 hCG samples >5 IU/L taken between January 2000 and June 2004.

CONCLUSIONS

A single serum hCG determination on day 14 or 15 is sufficient to discriminate viable pregnancies accurately from non-viable pregnancies.

Luteal hormonal profile of oocyte donors stimulated with a GnRH antagonist compared with natural cycles

The effect of gonadotrophin-releasing hormone (GnRH) antagonist treatment on luteal phase hormonal profile has not yet been fully investigated. Cycle characteristics of 23 fertile donors stimulated with recombinant FSH and the GnRH antagonist, ganirelix 0.25, for IVF and receiving no kind of luteal supplementation were compared with control, natural cycles. Luteal luteinizing hormone (LH) serum concentrations as well area under the curve (AUC) for LH were significantly higher in natural cycles. In addition, luteal phase length was longer in natural cycles compared with donor cycles. Luteinizing hormone values dropped in the luteal phase of the stimulated cycles, with the lowest values being observed in the mid-luteal phase. AUC for progesterone in the luteal phase was significantly higher in the stimulated cycles compared with natural cycles (P < 0.001). Low LH serum concentrations and shortened luteal phase indicate the need for luteal phase supplementation in GnRH antagonist IVF cycles.

The place of gonadotrophin-releasing hormone antagonists in reproductive medicine

Gonadotrophin-releasing hormone (GnRH) antagonists have recently been introduced into clinical practice. They appear to offer a promising alternative to the long-established GnRH agonist regimens for prevention of a premature LH surge during ovarian stimulation for assisted reproductive techniques. Clinical outcomes achieved with antagonists are comparable with those of a long GnRH agonist protocol, while treatment times and gonadotrophin requirements are reduced and safety is improved. In particular, the antagonists appear to be associated with a lower risk of ovarian hyperstimulation syndrome (OHSS) than do agonists. Patient surveys suggest a preference for antagonist over agonist treatment cycles. These benefits suggest that GnRH antagonists have the potential to replace agonists as the treatment of choice in ovarian stimulation for assisted reproductive techniques. Two agents, cetrorelix and ganirelix, are currently in clinical use. Cetrorelix is available in single- and multiple-dose formulations, offering increased flexibility compared with ganirelix.

Use of gonadotrophin-releasing hormone agonists to trigger ovulation

The introduction of gonadotrophin-releasing hormone (GnRH) agonists combined with gonadotrophins is considered to be one of the most significant advances in the development of in vitro fertilization (IVF) treatment. However, ovarian hyperstimulation syndrome (OHSS) remains a significant complication of controlled ovarian hyperstimulation. One possible strategy to reduce the risk of this complication would be the use of GnRH agonists instead of human chorionic gonadotrophin (hCG) to trigger the final stages of oocyte maturation. GnRH agonists are able to induce an endogenous surge of luteinizing hormone (LH) and follicle-stimulating hormone (FSH) and the effect may be more physiological than that of exogenous hCG. Several uncontrolled and controlled clinical studies have confirmed the efficacy of GnRH agonists for triggering ovulation, and pregnancy rates are comparable to those achieved with hCG. The incidence of OHSS appears to be decreased, but larger controlled studies are required to confirm this observation. The recent introduction of GnRH antagonists has led to renewed interest in the use of GnRH agonists to induce final oocyte maturation. An international multicentre randomized controlled trial has been completed recently comparing the efficacy of GnRH agonist with hCG for triggering ovulation in women undergoing controlled ovarian hyperstimulation using the GnRH antagonist ganirelix for pituitary suppression. The aim of the study was to determine the efficacy of the novel protocol for ovarian stimulation before IVF, in terms of pregnancy outcomes and the prevention of OHSS.

Periovulatory serum human chorionic gonadotropin (hCG) concentrations following subcutaneous and intramuscular nonrecombinant hCG use during ovulation induction: a prospective, randomized trial

OBJECTIVE

To describe serum levels of human chorionic gonadotropin (hCG) as a function of hCG injection method (subcutaneous vs. intramuscular) among infertile women undergoing ovulation induction.

DESIGN

Prospective, randomized clinical trial.

SETTING

Major urban infertility referral center.

PATIENT(S)

Women presenting for infertility evaluation and ovulation induction.

INTERVENTION(S)

Controlled ovarian hyperstimulation was followed by 5,000 IU urinary (nonrecombinant) hCG injection, given intramuscularly (i.m.) or subcutaneously (s.c.).

MAIN OUTCOME MEASURE(S)

Serum hCG levels measured 24 hours after administration of hCG, and patient tolerability of injected hCG.

RESULT(S)

There were no statistically significant differences in age or body mass index (BMI) among patients receiving hCG s.c. (n = 13) or i.m. (n = 15). Mean [IQR (25; 75)] serum hCG levels in the s.c. and i.m. groups were 171.7 [27.0; 207.0] and 142.2 [102.5; 157.5] mIU/mL, respectively. No adverse events were registered by any patient receiving hCG by either injection method. In this non-IVF population, two pregnancies were established in each subgroup (4 of 28, or approximately 14% pregnancy rate).

CONCLUSION(S)

The s.c. administration of 5,000 IU hCG (reconstituted in vol. = 0.5 mL) was well tolerated by all women in this study and was associated with postinjection serum hCG levels similar to those observed after administration of an equivalent i.m. hCG dose. This investigation suggests that clinical use of s.c. hCG is suitable for lean women (e.g., BMI <30) undergoing ovulation induction, but additional data are needed to study the appropriateness of s.c. hCG administration in heavier patients.

Comparison of LH concentrations in the early and mid-luteal phase in IVF cycles after treatment with HMG alone or in association with the GnRH antagonist Cetrorelix

Luteinizing hormone (LH) is mandatory for the maintenance of the corpus luteum. Ovarian stimulation for IVF has been associated with a defective luteal phase. The luteal phases of two groups of patients with normal menstrual cycles and no endocrinological cause of infertility were retrospectively analysed in IVF cycles. Thirty-one infertile patients stimulated with human menopausal gonadotrophins (HMG) for IVF to whom the gonadotrophin-releasing hormone (GnRH) antagonist Cetrorelix 0.25 mg was also administered to prevent the LH surge (group I) were compared with 31 infertile patients stimulated with HMG alone (group II). Despite differences in the stimulation outcome, luteal LH serum concentrations were similar in the two groups. LH values dropped from 2.3 +/- 1 IU/l on the day of human chorionic gonadotrophin (HCG) administration to 1.1 +/- 0.7 IU/l on day HCG +2 in group I (P < 0.0001) and from 5.1 +/- 3 to 1.2 +/- 1.7 IU/l (P < 0.0001) in group II. In the mid-luteal phase, LH concentrations were low in both groups. Our results suggest that suppressed LH concentrations in the early and mid-luteal phase may not be attributed solely to the GnRH-antagonist administration. Pituitary LH secretion may be inhibited by supraphysiological steroid serum concentrations via long-loop feedback and/or by the central action of the exogenously administered HCG via a short-loop mechanism.