Pharmacokinetic and pharmacodynamic interactions between recombinant human luteinizing hormone and recombinant human follicle-stimulating hormone

A real-world study of ART in France (REOLA) comparing a biosimilar rFSH against the originator according to rFSH starting dose

BACKGROUND

Since the first launch of a biosimilar recombinant follicle stimulating hormone (rFSH), Bemfola®, in Europe in 2014, it has been possible to study in routine clinical care throughout France the effectiveness of a biosimilar rFSH including according to different rFSH starting doses.

METHODS

REOLA was a non-interventional, retrospective, real world study using anonymized data from 17 Assisted Reproductive Technology (ART) centres' data management systems across France including 2,319 ART ovarian stimulation cycles with Bemfola® and 4,287 ART ovarian stimulation cycles with Gonal-f®. For both products, four populations were studied according to starting dose of rFSH: < 150 IU, 150 - 224 IU, 225 - 299 IU and ≥ 300 IU. The primary endpoint was the cumulative live birth rate (cLBR) per commenced ART ovarian stimulation cycle including all subsequent fresh and frozen-thawed embryo transfers starting during a follow up period of at least 1 year following oocyte retrieval.

RESULTS

A direct relationship of increasing rFSH starting dose with increasing age, increasing basal FSH, decreasing AMH and increasing body mass index was noted. No clinically relevant differences were seen in all outcomes reported, including the cLBR, between Bemfola® and Gonal-f®, but for both drugs, an association was seen with increasing rFSH starting dose and decreasing cLBR.

CONCLUSIONS

The REOLA study demonstrates that the cLBR with Bemfola® is very similar to Gonal-f® across all patient subpopulations. The cLBR is inversely related to the rFSH starting dose irrespective of the drug used, and the REOLA study provides reassurance of the clinical effectiveness of a biosimilar rFSH used in a real world setting.

Dynamic changes in LH/FSH ratios in infants with normal sex development

OBJECTIVE

Little is known about the ratio between luteinizing hormone (LH) and follicle-stimulating hormone (FSH) during infancy. This study aimed to evaluate serum and urinary LH/FSH as a marker of sex with age-specific cutoffs in healthy infants.

DESIGN

A prospective, longitudinal cohort study of healthy infants aged 0-1.2 years.

METHODS

In total, 236 healthy infants (122 boys and 114 girls) from The COPENHAGEN Minipuberty Study (ClinicalTrials.gov ID: NCT02784184), with 567 serum and 603 urine samples, were included. Measures of diagnostic accuracy, including sensitivity and specificity, were used to assess the ability of LH/FSH to detect sex in healthy infants.

RESULTS

In both serum and urine, LH/FSH was highest in males with minimal overlap between the sexes. In contrast to isolated LH and FSH concentrations, LH/FSH ratios in both serum and urine were excellent markers of sex from 0 to 1.2 years with median sensitivities and specificities ranging from 93 to 100% with correspondingly narrow 95% CIs.

CONCLUSIONS

Serum and urinary LH/FSH ratios are excellent discriminators of sex in healthy infants during the entire first year of life. The clinical role and application of the ratio remain to be elucidated.

The impact of polycystic ovary syndrome and body mass index on the absorption of recombinant human follicle stimulating hormone

PURPOSE

Women with polycystic ovary syndrome (PCOS) have an increased ovarian responsiveness to exogenous recombinant follicle stimulating hormone (rFSH) but also have high rates of obesity, which is known to affect serum FSH concentrations following exogenous injection. The purpose of this study was to compare rFSH absorption and ovarian response between lean and overweight/obese PCOS subjects and normo-ovulatory controls.

METHODS

Fourteen women with PCOS aged 18-42 years old with a BMI of 18.5-24.9 kg/m2 (normal) or 25.0-40.0 kg/m2 (overweight/obese) and eleven normo-ovulatory controls matched by age and BMI were included. After downregulation with oral contraceptives, participants were administered a single subcutaneous injection of 225 IU rFSH and underwent serial blood draws over 72 h.

RESULTS

Lean PCOS subjects exhibited a significantly higher area under the curve (AUC) of baseline-corrected serum FSH over 72 h when compared with overweight/obese PCOS subjects (183.3 vs 139.8 IU*h/L, p = 0.0002), and lean, normo-ovulatory women had a significantly higher AUC FSH when compared with overweight/obese, normo-ovulatory women (193.3 vs 93.8 IU*h/L, p < 0.0001). Within overweight/obese subjects, those with PCOS had a significantly higher AUC FSH compared with normo-ovulatory controls (p = 0.0002). Lean PCOS subjects similarly had the highest AUC of baseline-corrected estradiol (6095 pg h/mL), compared with lean normo-ovulatory subjects (1931 pg h/mL, p < 0.0001) and overweight/obese PCOS subjects (2337 pg h/mL, p < 0.0001).

CONCLUSION

Lean PCOS subjects exhibited significantly higher baseline-corrected FSH and estradiol levels following rFSH injection compared with overweight/obese PCOS subjects with similar ovarian reserve markers. Amongst overweight/obese subjects, those with PCOS had significantly higher FSH and E2 levels when compared with normo-ovulatory controls.

Population Pharmacokinetic Modelling of FE 999049, a Recombinant Human Follicle-Stimulating Hormone, in Healthy Women After Single Ascending Doses

Objective

The purpose of this analysis was to develop a population pharmacokinetic model for a novel recombinant human follicle-stimulating hormone (FSH) (FE 999049) expressed from a human cell line of foetal retinal origin (PER.C6^®) developed for controlled ovarian stimulation prior to assisted reproductive technologies.

Methods

Serum FSH levels were measured following a single subcutaneous FE 999049 injection of 37.5, 75, 150, 225 or 450 IU in 27 pituitary-suppressed healthy female subjects participating in this first-in-human single ascending dose trial. Data was analysed by nonlinear mixed effects population pharmacokinetic modelling in NONMEM 7.2.0.

Results

A one-compartment model with first-order absorption and elimination rates was found to best describe the data. A transit model was introduced to describe a delay in the absorption process. The apparent clearance (CL/F) and apparent volume of distribution (V/F) estimates were found to increase with body weight. Body weight was included as an allometrically scaled covariate with a power exponent of 0.75 for CL/F and 1 for V/F.

Conclusions

The single-dose pharmacokinetics of FE 999049 were adequately described by a population pharmacokinetic model. The average drug concentration at steady state is expected to be reduced with increasing body weight.

Characterisation of Population Pharmacokinetics and Endogenous Follicle-Stimulating Hormone (FSH) Levels After Multiple Dosing of a Recombinant Human FSH (FE 999049) in Healthy Women

Objective

The aim of this study was to characterise the population pharmacokinetics of FE 999049, a novel recombinant human follicle-stimulating hormone (FSH), after multiple dosing in healthy women, taking into account endogenous FSH levels and the reproductive hormone dynamics.

Methods

Longitudinal measurements of FSH, luteinising hormone, progesterone, estradiol, and inhibin B levels were collected after repeated subcutaneous dosing with 225 IU of FE 999049 in 24 gonadotropin downregulated healthy women. The FSH data were described using nonlinear mixed-effects modelling.

Results

The measured FSH levels were modelled as a sum of endogenous FSH and FE 999049. The FE 999049 population pharmacokinetics were best described using a one-compartment model with first-order absorption and elimination, and a transit model for delayed absorption. The apparent clearance and volume of distribution increased with body weight in accordance with an allometrically scaled power exponent of 0.75 and 1, respectively. Endogenous FSH levels were lower in individuals with higher progesterone levels at baseline and were further suppressed over time with increasing inhibin B levels.

Conclusions

This characterisation of FE 999049 population pharmacokinetics after repeated dosing is in line with previous findings after single-dose administration. The results provide a basis for study design and data evaluation in the future development of recombinant FSH products, and show it can be of importance to account for endogenous FSH levels and its variation over time for accurate estimation of exogenously administered FSH pharmacokinetic parameters. Thus, correcting FSH concentrations by the observed endogenous FSH baseline value at all time points may be incorrect.

Pharmacokinetic, pharmacodynamic, and clinical aspects of ovulation induction agents: A review of the literature

Controlled ovarian hyperstimulation is a key step for successful outcomes of assisted reproductive technique cycle outcomes. Many medications are available, which are commonly useed solely or in combination to achieve multiple follicular development. Pharmacokinetic, pharmacodynamic, and clinical information of ovulation induction drugs deserve to be elucidated for every individual patient before commencing infertility treatment. New concepts and new treatment protocols are introduced as ovulation physiology is understood by infertility specialists. Increasing treatment success by minimizing aderse effects is a milestone of all ovarian stimulation protocols that use these novel interventions. Achievement of a satisfactory cycle outcome includes retrieval of sufficient oocytes, a single clinical pregnancy, and avoidance of ovarian hyperstimulation syndrome. In this review, we evaluate the current literature to determine the most reliable and relevant information about the most used ovulation induction drugs.

Pharmacokinetics and Pharmacodynamics of Follicle-Stimulating Hormone in Healthy Women Receiving Single and Multiple Doses of Highly Purified Human Menotrophin and Urofollitrophin

BACKGROUND AND OBJECTIVE

Highly purified human menotrophin and urofollitrophin preparations obtained from human urine via a novel patented purification method have been tested over a timeframe of 14 years in the studies presented in this article. The objective of the studies was to investigate the pharmacokinetics and the pharmacodynamics of follicle-stimulating hormone (FSH) after single subcutaneous and intramuscular doses and multiple subcutaneous doses of the tested preparations in healthy fertile pituitary-suppressed women.

DESIGNS

We performed five open, randomised, crossover, single-dose bioequivalence and/or bioavailability studies and one open, multiple-dose, pharmacokinetics and pharmacodynamics study.

STUDY SUBJECTS AND TREATMENTS

The six studies included 121 healthy fertile women taking their usual combined oral contraceptives for 3 months before the study: Study 1: 300 international units (IU) of highly purified menotrophin as single subcutaneous and intramuscular doses. Study 2: 300 IU of highly purified menotrophin (test formulation vs. comparator) as single subcutaneous doses. Study 3: 300 IU of highly purified urofollitrophin (hp-FSH) (test formulation vs. comparator) as single subcutaneous doses. Study 4: 300 IU (2 × 150 IU vs. 4 × 75 IU) of hp-FSH as single subcutaneous doses. Study 5: 225 and 445 IU of hp-FSH as single subcutaneous doses. Study 6: daily 225 IU of hp-FSH as subcutaneous doses for 5 consecutive days.

MAIN OUTCOME MEASURES

The main outcome measures were the FSH pharmacokinetic parameters, estradiol concentrations, and the number and size of the follicles.

RESULTS

FSH after single subcutaneous and intramuscular injections of menotrophin or urofollitrophin attained a systemic peak (maximum) concentration (C _max) that was on average consistent throughout the first four studies and ranged from 4.98 to 7.50 IU/L. The area under the plasma concentration-time curve (AUC) from administration to the last observed concentration time t (AUC_t) ranged from 409.71 to 486.16 IU/L·h and the elimination half-life (t _½) ranged from 39.02 to 53.63 h. After multiple doses of urofollitrophin (225 IU) for 5 days, FSH attained a mean C _max of 14.93 ± 2.92 IU/L and had an AUC during the time interval τ between two consecutive doses at steady state (AUC_τ) of 322.59 ± 57.92 IU/L·h, which was similar to the mean AUC_t after a single subcutaneous dose of 225 IU of urofollitrophin in study 5 (306.82 ± 68.37 IU/L·h).

CONCLUSIONS

In our studies, the intramuscular and subcutaneous routes of menotrophin were equivalent; both menotrophin and urofollitrophin were bioequivalent to their marketed reference; FSH kinetic parameters following injection of urofollitrophin were dose proportional and independent from the administered concentration; and multiple doses of FSH increased estradiol levels and enhanced growth of follicles with a good dose-response correlation. Local tolerability was excellent throughout the six studies.

Open-Label, Randomized, Two-Way, Crossover Study Assessing the Bioequivalence of the Liquid Formulation versus the Freeze-Dried Formulation of Recombinant Human FSH and Recombinant Human LH in a Fixed 2:1 Combination (Pergoveris®) in Pituitary-Suppressed Healthy Women

This was a Phase I, open-label, randomized, two-period, two-sequence crossover study [ClinicalTrials.gov NCT02317809 (https://www.clinicaltrials.gov/ct2/show/NCT02317809); EudraCT 2014-003506-32] assessing the bioequivalence of the liquid and freeze-dried formulations of fixed-dose, fixed-ratio (2:1) combination recombinant human follicle-stimulating hormone plus recombinant human luteinizing hormone (r-hFSH/r-hLH). The safety and tolerability of the two formulations were also assessed. Healthy premenopausal women were randomized to one of two crossover dosing schedules. Subjects in Treatment Sequence 1 received a single subcutaneous dose (900/450 IU r-hFSH/r-hLH) of the liquid formulation of r-hFSH/r-hLH on Day 1 of Dose Period 1 and, after a washout period of at least 14 days, a single subcutaneous dose (900/450 IU r-hFSH/r-hLH) of the freeze-dried formulation of r-hFSH/r-hLH (reconstituted in water for injection prior to administration) on Day 1 of Dose Period 2. Subjects in Treatment Sequence 2 received the treatments in reverse order. The primary endpoints were AUC_0-t (area under the serum concentration-time curve from time 0 to the time of the last quantifiable concentration) and C_max (maximum serum concentration) for FSH and LH, both baseline corrected. A total of 34 subjects were randomized, and 22 subjects were included in the bioequivalence evaluation. Overall, the mean observed PK profiles and individual PK parameters were comparable for the liquid and freeze-dried formulations, although a median difference in the t_max (time to reach maximum observed concentration) of FSH of ~4.5 h was observed between the formulations. The calculated 90% confidence intervals of the mean liquid formulation/freeze-dried formulation ratios for C_max and AUC_0-t were within the bioequivalence range (80-125%) for both LH and FSH, confirming bioequivalence between the two formulations. The safety and tolerability profiles of the two formulations were similar. The liquid formulation can, therefore, be expected to provide the same efficacy as the freeze-dried formulation, with no differences in tolerability.

Clinical Applications of Gonadotropins in the Male

The pituitary gonadotropins, luteinizing hormone (LH), and follicle-stimulating hormone (FSH) play a pivotal role in reproduction. The synthesis and secretion of gonadotropins are regulated by complex interactions among several endocrine, paracrine, and autocrine factors of diverse chemical structure. In men, LH regulates the synthesis of androgens by the Leydig cells, whereas FSH promotes Sertoli cell function and thereby influences spermatogenesis. Gonadotropins are complex molecules composed of two subunits, the α- and β-subunit, that are noncovalently associated. Gonadotropins are decorated with glycans that regulate several functions of the protein including folding, heterodimerization, stability, transport, conformational maturation, efficiency of heterodimer secretion, metabolic fate, interaction with their cognate receptor, and selective activation of signaling pathways. A number of congenital and acquired abnormalities lead to gonadotropin deficiency and hypogonadotropic hypogonadism, a condition amenable to treatment with exogenous gonadotropins. Several natural and recombinant preparations of gonadotropins are currently available for therapeutic purposes. The difference between natural and the currently available recombinant preparations (which are massively produced in Chinese hamster ovary cells for commercial purposes) mainly lies in the abundance of some of the carbohydrates that conform the complex glycans attached to the protein core. Whereas administration of exogenous gonadotropins in patients with isolated congenital hypogonadotropic hypogonadism is a well recognized therapeutic approach, their role in treating men with normogonadotropic idiopathic infertility is still controversial. This chapter concentrates on the main structural and functional features of the gonadotropin hormones and how basic concepts have been translated into the clinical arena to guide therapy for gonadotropin deficit in males.

Dose-exposure proportionality of a novel recombinant follicle-stimulating hormone (rFSH), FE 999049, derived from a human cell line, with comparison between Caucasian and Japanese women after subcutaneous administration

Background and Objectives

FE 999049 is a novel recombinant follicle-stimulating hormone (rFSH) preparation expressed by a human cell line (PER.C6^®), in contrast to existing rFSH preparations expressed by Chinese hamster ovary (CHO) cell lines. Since the individual dose of rFSH may be altered depending on the response in women undergoing assisted reproductive technologies, knowledge on the dose-exposure linearity and proportionality is important. The purpose of these studies was to investigate the dose-exposure linearity and proportionality properties of FE 999049 with a comparison between Caucasian and Japanese women. This is the first study in Japanese women regarding pharmacokinetics of rFSH.

Methods

Forty-eight Caucasian and 31 Japanese healthy women of reproductive age were pituitary down-regulated to suppress endogenous FSH. Following single subcutaneous administration of 37.5, 75, 150, 225, or 450 IU (Steelman–Pohley assay), the serum FSH concentration was followed over 10 days.

Results

The dose-dependent pharmacokinetic parameters of FE 999049, area under the serum concentration-time curve (AUC) and maximum serum concentration (C_max), showed dose-exposure linearity and proportionality over 150–450 IU in Caucasian women, the dose interval available for analysis, and 75–450 IU in Japanese women, which was the dose interval investigated. Comparison between Caucasian and Japanese women showed no differences between the populations. The dose-independent parameters were similar over all doses in both populations. FE 999049 was safe and well tolerated at all doses in both populations with few, mostly mild, adverse events.

Conclusion

The results demonstrate dose-exposure proportionality and a predictable dose-dependent exposure of FE 999049, with no differences in Caucasian and Japanese women of reproductive age.

Gonadotrophins: The future

The role of the IVF clinician is to make the ART treatment safe, patient-friendly, cost effective and at the same time offer good and high quality treatment. IVF protocols are a burden for women and are one of the potential reasons why women don’t return for subsequent cycles. Frequent injections may increase stress and also result in high error rates. Simple short treatment regimen with optimal recovery of good quality oocytes results in development of good quality embryos followed by SET in treatment and cryopreservation cycles are a less burden and result in related lesser discontinuation, side effects, treatment cycles in time and are more cost-effective.

Development of FSH analogues with longer terminal t1/2 and slower absorption to peak serum levels will increase the efficiency, decrease the side effects and also is easy to administer. This makes it convenient for the patients increasing the compliance. A certain minimum LH concentration is necessary for adequate thecal cell function and subsequent oestradiol synthesis in the granulosa cells. Adjuvant r-HLH gives clinician's precise control over the dose of LH bioactivity administered to target the therapeutic window. New parenteral, transdermal, inhaled and oral fertility drugs and regimens are currently under research and development with the objective to further simplify treatment for ART.

Early stage development of the glycine-1 re-uptake inhibitor SCH 900435: central nervous system effects compared with placebo in healthy men

AIMS

To report the first three studies with SCH 900435, a selective glycine-1 re-uptake inhibitor in development for treating schizophrenia, using systematic evaluations of pharmacodynamics to understand the observed effects.

METHODS

Three double-blind, placebo-controlled studies (single, visual effect and multiple dose) were performed. In the single and multiple dose study SCH 900435 (0.5-30 mg) was given to healthy males and frequent pharmacokinetic and pharmacodynamic measurements were performed. The visual effects study incorporated visual electrophysiological measures of macular, retinal and intracranial visual pathway function.

RESULTS

In the single dose study (highest difference, 95% CI, P) increases in smooth pursuit eye movements (8, 12 mg (-6.09, 10.14, -2.04, 0.013), 30 mg), pupil : iris ratio (20 and 30 mg (-0.065, 0.09, -0.04, <0.0001)), VAS colour perception (30 mg (-9.48, 13.05, -5.91, <0.0001)) and changes in spontaneous reports of visual disturbance were found, while FSH (8 mg (0.42, 0.18, 0.66, 0.0015), 12, 20 mg), LH (8-30 mg (1.35, 0.65, 2.05, 0.0003)) and EEG alpha2 activity decreased (12, 20, 30 mg (0.27, 0.14, 0.41, 0.0002)). A subsequent dedicated visual effects study demonstrated that visual effects were transient without underlying electrophysiological changes. This provided enough safety information for starting a multiple ascending dose study, showing less visual symptoms after twice daily dosing and titration, possibly due to tolerance.

CONCLUSIONS

Several central nervous system (CNS) effects and gonadotropic changes resulted from administration of 8 mg and higher, providing evidence for CNS penetration and pharmacological activity of SCH 900435. Antipsychotic activity in patients, specificity of the reported effects for this drug class and possible tolerance to visual symptoms remain to be established.

Outcome from consecutive ICSI cycles in patients treated with recombinant human LH and those supplemented with urinary hCG-based LH activity during controlled ovarian stimulation in the long GnRH-agonist protocol

Clinical results were compared in a well-established, assisted reproduction program during the cross-over from highly purified (HP)-human menopausal gonadotropin (hMG) to rhFSH/rhLH. We included the last 33 patients treated with HP-hMG and the first 33 patients receiving rhFSH/rhLH for ovarian stimulation in their first intracytoplasmic sperm injection cycle. Patient baseline characteristics were almost identical in the two groups. Ovarian stimulation characteristics (days of stimulation, total amount of FSH administered using a modest initial loading dose of 150 IU/d, patients with oocyte retrieval) were similar for the two groups. However, the number of total and leading follicles and E2 serum levels on the human chorionic gonadotropin injection day were significantly higher in the rhFSH/rhLH group. The oocyte yield was significantly higher in the rhFSH/rhLH group as well as the number of metaphase II oocytes, difference almost reaching the statistical significance. The number of oocytes fertilized was also higher in patients receiving rhFSH/rhLH treatment. Implantation and clinical pregnancy rates were similar in both the study groups. It is concluded that in women undergoing controlled ovarian hyperstimulation under pituitary suppression for ART, the recombinant combined product containing FSH and LH in a fixed 2:1 ratio is more effective than HP-hMG in terms of follicle development, oocyte yield and quality, and fertilization rates.

Split daily recombinant human LH dose in hypogonadotrophic hypogonadism: a nonrandomized controlled pilot study

This prospective controlled nonrandomized pilot study was conducted to investigate whether split daily doses of recombinant human LH (rHLH) is more efficacious than the single daily dose in supporting follicular development and ovulation in primary hypogonadotrophic hypogonadism (HH). Twenty-seven women with HH received a 150 IU fixed daily subcutaneous dose of recombinant human FSH, supplemented by 75 IU daily dose of rHLH given either as a single dose (n=9; single-dose group) or four equally divided doses (n=18; split-dose group). Ovulation was defined by three efficacy end points: at least one follicle ⩾17mm in diameter, pre-ovulatory serum oestradiol ⩾400pmol/l and a midluteal progesterone ⩾25nmol/l. Although lacking statistical significance, the proportion of women in the rHLH split-dose group who fulfilled all three end points was higher than the single-dose group (72.2% versus 55.6%). Women in the split-dose group achieved higher serum oestradiol concentrations per follicle, endometrial thickness measurements and numbers of follicles than in the single-dose group (not statistically significant). The odds ratio for ovulation rate was 2.08 (not statistically significant). There were no serious untoward side effects. Administering rHLH in split daily doses could provide superior results compared with the traditional single daily dose. We conducted this clinical study to investigate whether a split daily dose protocol of recombinant human LH (rHLH) is more efficacious than the single daily dose in supporting follicular development and ovulation in primary hypogonadotrophic hypogonadism (HH). HH is an uncommon entity that can lead to very low or undetectable serum gonadotrophin concentrations. It manifests in anovulation, amenorrhoea and subsequent infertility. Twenty-seven women with HH received a 150 IU fixed daily subcutaneous dose of recombinant human FSH, supplemented by a 75 IU daily dose of rHLH given either as a single dose (n=9; single-dose group) or four equally divided doses (n=18; split-dose group). Ovulation was defined by these three efficacy end points: at least one follicle ⩾17mm in mean diameter, pre-ovulatory serum oestradiol concentration ⩾400pmol/l and a midluteal progesterone concentration ⩾25nmol/l. The proportion of women in the rHLH split-dose group who fulfilled all three end points was higher than the single-dose group (72.2% versus 55.6%). Women in the split-dose group achieved higher serum oestradiol concentrations per follicle, endometrial thickness measurements and numbers of follicles than in the single-dose group, without statistical significance. Women who received the split-dose regimen were more likely to have ovulation than the other group. We had no serious problematic side effects. Our results suggest that administering rHLH in split daily doses could provide superior results compared to the traditional single daily dose.

Endocrinological insights into different in vitro fertilization treatment aspects

The science of reproductive endocrinology/in vitro fertilization (IVF) has moved forward considerably since the first IVF baby was born in 1978. IVF was originally indicated for women with tubal factor infertility, but it has now become the treatment for couples with unexplained subfertility, male subfertility, cervical factor, failed ovulation induction, endometriosis or unilateral tubal pathology. IVF was initially performed with the single dominant ovarian follicle produced during a spontaneous menstrual cycle. This was very inefficient and pregnancy rates were dismal. Consequently, superovulation protocols using parenteral gonadotrophins to induce maturation of multiple follicles were soon adopted worldwide. In addition, any supernumerary embryos remaining after embryo transfer may be cryopreserved for future embryo transfers without the need for another fresh IVF cycle. A greater understanding of IVF endocrinology has led to improved IVF pregnancy outcomes and satisfaction for the anxious parents. However, with the greater success of IVF treatment, new complications associated with the treatment arise, namely the ovarian hyperstimulation syndrome. Ovarian hyperstimulation can be associated with severe morbidity and may be even fatal. Ovarian hyperstimulation syndrome is an iatrogenic condition secondary to medical stimulation of the ovary, and was virtually unknown until IVF treatment was initiated. This article will discuss the recent developments in IVF treatment endocrinology and protocols, as well as prevention/treatment of its complications.

Does exogenous LH in ovarian stimulation improve assisted reproduction success? An appraisal of the literature

A review of the scientific literature on the use of exogenous LH in assisted reproductive technology was performed by searching the MEDLINE, PubMed and Cochrane online databases. Scientific evidence was reviewed comparing recombinant FSH-only protocols to protocols supplemented with exogenous LH activity: human menopausal gonadotrophin (HMG), recombinant LH and mid-follicular human chorionic gonadotrophin (HCG). Studies were further compared based on pituitary suppression with gonadotrophin- releasing hormone (GnRH) antagonist and agonist protocols. Primary focus was given to randomized controlled trials and meta-analyses. Data from hypogonadotrophic hypogonadal patients demonstrated the importance of LH activity for success of assisted reproduction treatment. However, the majority of normogonadotrophic patients had adequate endogenous LH to successfully drive ovarian steroidogenesis and oocyte maturation. Exogenous LH supplementation was consistently associated with higher peak oestradiol concentrations. The use of HMG in long GnRH agonist cycles was associated with a 3–4% increase in live birth rate. There was insufficient evidence to make definitive conclusions on the need for exogenous LH activity in GnRH antagonist cycles or the benefit of recombinant LH and HCG protocols. Poor responders and patients 35 years of age and older may benefit from exogenous LH.

A 2:1 formulation of follitropin alfa and lutropin alfa in routine clinical practice: a large, multicentre, observational study

BACKGROUND

A 2:1 (150 IU:75 IU) follitropin alfa:lutropin alfa formulation has been developed. A 3-year post-marketing surveillance study is ongoing in Germany to explore the use of this formulation in routine clinical practice.

MATERIALS AND METHODS

An 11-month interim analysis of data from assisted reproductive technology (ART) cycles only is described.

RESULTS

Data were available from 857 patients undergoing 919 cycles of ART at 19 centres. Most patients (58.7%) were aged ≥ 35 years, and many (41.3%) were undergoing their first ART cycle. Main reasons cited by physicians for prescribing this formulation were poor response in a previous treatment cycle (n = 303) and low basal luteinizing hormone (LH) level (n = 107). Mean (standard deviation) duration of ovarian stimulation was 10.8 (2.6) days. In 90.7% of cycles, the 2:1 formulation was administered throughout the stimulation period. Most frequent LH daily dose was 75 IU. Embryo transfer was conducted in 741 cycles; clinical pregnancy rate per transfer was 27.5%. Three cases of ovarian hyperstimulation syndrome developed in three patients (3/741 [0.4%] cycles); one required hospitalization. No other major safety events were reported.

CONCLUSION

This interim analysis shows that use of the 2:1 formulation for ovarian stimulation during routine ART procedures is effective in achieving clinical pregnancies and is associated with a positive safety profile.

Current opinion on use of luteinizing hormone supplementation in assisted reproduction therapy: an Asian perspective

LH and FSH have complementary functions in ensuring optimal oocyte maturation and ovulation. In women undergoing assisted reproduction technology protocols with gonadotrophin-releasing hormone analogues, LH and FSH concentrations are reduced. While FSH use in assisted reproduction technology is well established, there is no published consensus on the need for exogenous LH in Asian patients. Having reviewed the concept of the LH therapeutic window and differences between recombinant human LH (r-HLH) and human menopausal gonadotrophin, a consensus was reached on which patient subgroups may benefit from LH supplementation. Adjuvant r-HLH gives clinicians precise control over the dose of LH bioactivity administered to target the therapeutic window. The use of r-HLH is recommended in women with poor response in a previous cycle or suboptimal follicular progression in a current cycle by day 6-8 of stimulation. r-HLH should also be considered in women at risk of suboptimal response, specifically age > 35 years. Other risk markers that suggest the need for LH supplementation, which include baseline/day-6 serum LH and anti-Müllerian hormone concentrations, antral follicle count and LH polymorphisms require further research and verification. For measurement of LH response adequacy, the monitoring of follicular progression, oestradiol concentrations and endometrial thickness is recommended.

Glycosylation of therapeutic proteins: an effective strategy to optimize efficacy

During their development and administration, protein-based drugs routinely display suboptimal therapeutic efficacies due to their poor physicochemical and pharmacological properties. These innate liabilities have driven the development of molecular strategies to improve the therapeutic behavior of protein drugs. Among the currently developed approaches, glycoengineering is one of the most promising, because it has been shown to simultaneously afford improvements in most of the parameters necessary for optimization of in vivo efficacy while allowing for targeting to the desired site of action. These include increased in vitro and in vivo molecular stability (due to reduced oxidation, cross-linking, pH-, chemical-, heating-, and freezing-induced unfolding/denaturation, precipitation, kinetic inactivation, and aggregation), as well as modulated pharmacodynamic responses (due to altered potencies from diminished in vitro enzymatic activities and altered receptor binding affinities) and improved pharmacokinetic profiles (due to altered absorption and distribution behaviors, longer circulation lifetimes, and decreased clearance rates). This article provides an account of the effects that glycosylation has on the therapeutic efficacy of protein drugs and describes the current understanding of the mechanisms by which glycosylation leads to such effects.

Effects of recombinant human LH and hCG on serum and urine LH and androgens in men

CONTEXT

The administration of gonadotrophins is prohibited in sport but the effect in men of recently available recombinant hCG and LH on serum and urine concentrations of gonadotrophins and androgens has not been systematically evaluated in the antidoping context.

OBJECTIVE

To determine the time-course of recombinant LH (rhLH) and hCG (rhCG) on blood and urine hormone profiles in men to develop effective tests to detect rhLH and rhCG doping.

DESIGN

Two randomized controlled studies with a 2 x 2 factorial design.

SETTING

Academic research centre.

PARTICIPANTS

Healthy male volunteers aged 18-45 years.

INTERVENTIONS

In the rhLH study, men were randomized into (i) either of two single doses of rhLH (75 IU or 225 IU), and (ii) suppression of endogenous LH and testosterone by nandrolone or no suppression. In the rhCG study, men were randomized into (i) either of two single doses of rhCG (250 or 750 microg), and (ii) suppression of endogenous LH and testosterone by nandrolone decanoate (ND) or no suppression. ND suppression comprised a single dose of 200 mg ND 3 days prior to, and in the rhCG study an additional dose 1 day after gonadotrophin injection.

MAIN OUTCOME MEASURES

Serum and urine hCG, LH, T, T : LH ratio, urine epitestosterone (E) and urine T : E ratio.

RESULTS

Neither rhLH dose produced a significant increase in serum or urine LH or T or in the T : E or T : LH ratios regardless of ND-induced suppression of endogenous LH and T. Nor did an even higher dose (750 IU) in three healthy men with unsuppressed gonadal axis. These findings were confirmed with two different commercial LH immunoassays together with adjustment for any influence of urine sediment and dilution. Both rhCG doses produced a steep, dose-proportional increase in serum and urine hCG with increases in serum and urine T and suppression of serum and urine LH, regardless of hCG dose. Serum but not urine T was lowered by ND suppression. The T : LH ratio showed a progressive increase unrelated to rhCG dose or ND suppression, whereas both rhCG and ND suppression minimally increased T : E ratio.

CONCLUSIONS

Both rhCG doses produce a striking increase in serum hCG and T with suppression of serum LH but, at single doses up to 750 IU, rhLH has no influence on serum or urine LH or T. Effective rhLH doping, which relies on a sustained increases in endogenous T, would require much higher and more frequent daily rhLH doses. Use of LH immunoassays optimized for serum to detect rhLH doping by urine LH measurement requires more standardization and validation and, at present, is unreliable. The T : LH ratio is, however, a useful screening test for hCG doping although its utility requires further evaluation.

Administration of follitropin alfa and lutropin alfa combined in a single injection: a feasibility assessment

BACKGROUND

Gonadotrophins are routinely administered in assisted reproductive technology (ART) treatment protocols. Recombinant human follicle-stimulating hormone (r-hFSH; follitropin alfa) and recombinant human luteinizing hormone (r-hLH; lutropin alfa) can be administered individually or in a fixed combination. The ability to vary the FSH to LH dose ratio in a single injection without compromising the bioactivity of either gonadotrophin or generating losses of active principle is important for physicians and patients alike.

METHODS

This study investigated whether follitropin alfa (GONAL-f ), as lyophilized powder for reconstitution or solution from the GONAL-f (filled-by-mass [FbM]) Prefilled Pen, could be used to reconstitute Pergoveris TM (follitropin alfa/lutropin alfa 150 IU/75 IU) lyophilized powder. In Ratio Groups 1 and 2, the r-hFSH:r-hLH ratio was 3:1; in Ratio Groups 3 and 4, the ratios of r-hFSH:r-hLH were 5:1 and 8:1, respectively. The protein content and bioactivity of each mixed solution were evaluated. The r-hFSH and r-hLH content was determined using reverse-phase high performance liquid chromatography. The biological activity of r-hFSH and r-hLH was assessed using the Steelman-Pohley and Van Hell in vivo bioassays in rats, respectively.

RESULTS

Follitropin alfa/lutropin alfa 150 IU/75 IU lyophilized powder could be successfully mixed with follitropin alfa 75 IU FbM solution that was either reconstituted from lyophilized powder or injected directly from the prefilled pen to create solutions with ratios of r-hFSH and r-hLH from 3:1 to 8:1. The measured content of r-hFSH and r-hLH corresponded favourably with the target protein content in Ratio Groups 1-4. The in vivo target and measured bioactivity of r-hFSH and r-hLH were also closely matched in all Ratio Groups.

CONCLUSION

Follitropin alfa lyophilized powder or solution can be accurately mixed with follitropin alfa/lutropin alfa 150 IU/75 IU lyophilized powder to enable physicians to administer ratios of r-hFSH and r-hLH in the IU range from 3:1 to 8:1. Mixing of recombinant formulations offers flexibility for patients receiving follitropin alfa and lutropin alfa for ART protocols in clinical practice.

Lutropin alfa

Lutropin alfa is the first and only recombinant human form of luteinizing hormone (LH) developed for use in the stimulation of follicular development. Dose-finding studies revealed a significant dose-dependent increase in the rate of optimal follicular development among women with hypogonadotropic hypogonadism and profound LH deficiency (<1.2 IU/L) who received subcutaneous lutropin alfa 0-225 IU/day plus follitropin alfa. Similarly, in a double-blind, randomized study, the rate of optimal follicular development was significantly higher in women with hypogonadotropic hypogonadism and profound LH deficiency receiving subcutaneous lutropin alfa 75 IU/day plus follitropin alfa than in those receiving placebo plus follitropin alfa. Lutropin alfa with follitropin alfa may also be of benefit in certain subgroups of normogonadotropic women (e.g. those with an inadequate response to prior follitropin alfa monotherapy, those aged >or=35 years, and those with profound LH downregulation or who required excessive exogenous follitropin alfa). However, one study in older women (>or=35 years) did not show any advantage of lutropin alfa supplementation. Once-daily subcutaneous lutropin alfa was generally well tolerated in hypogonadotropic hypogonadal women, with the majority of adverse events being of mild to moderate severity.

Follicular development induced by recombinant luteinizing hormone (LH) and follicle-stimulating hormone (FSH) in anovulatory women with LH and FSH deficiency: evidence of a threshold effect

OBJECTIVE

To assess the requirement for luteinizing hormone (LH) in women deficient in LH and follicle-stimulating hormone (FSH).

RESEARCH DESIGN AND METHODS

A prospective, randomized, parallel-group, multicentre study was carried out in tertiary care and academic medical centres. Women with anovulatory amenorrhoea > or = 1 year, serum oestradiol (E(2)) < 60 pg/mL (< 220 pmol/L) and low normal serum gonadotrophins were randomized in cycle A to a fixed daily dose of recombinant human (r-h) FSH (150 IU) and r-hLH 0, 25, 75 or 225 IU. Cycles B and C were not randomized.

MAIN OUTCOME MEASURES

Follicular development, ovulation and luteinization.

RESULTS

In cycle A, follicular development was achieved by 63.6% (7/11), 100% (9/9), 72.7% (8/11) and 66.7% (6/9) of patients who received r-hFSH and r-hLH 0, 25, 75 or 225 IU/day, respectively (p = not significant). Among patients with basal serum LH of < 1.2 IU/L, a dose-response relationship of r-hLH to follicular development was observed (p = 0.039). Fourteen of 34 patients (41.2%) wishing to conceive became pregnant. Among patients with hypogonadotrophic hypogonadism (HH) treated with r-hFSH alone, a transition from LH dependence to independence was observed between basal LH values of > or = 1.2 IU/L and < or = 1.6 IU/L. The r-hLH was well tolerated and no serious adverse events occurred during treatment. The most common treatment-related events were related to the reproductive system and the gastrointestinal tract.

CONCLUSIONS

Recombinant human LH provides a safe treatment option for women with HH. This small study also provided evidence suggestive of an LH threshold: follicular development was suboptimal when less than 75 IU/day r-hLH was administered.

New insights into the evolution of chorionic gonadotrophin

The glycoprotein hormones luteinizing hormone (LH) and chorionic gonadotrophin (CG) are crucial for reproduction, as LH induces sex hormone production and ovulation, and CG is essential for the establishment of pregnancy and fetal male sexual differentiation. Both consist of two heterodimeric peptides of which the alpha-subunit is common to both hormones whereas the beta-subunit is hormone-specific. The CGB gene was derived from LHB by gene duplication and frame shift mutation that led to a read-through into the formerly 3'-untranslated region, giving rise to the carboxyl-terminal peptide. Owing to nucleotide changes within the 5'-region of CGB, a new transcriptional start site and regulatory region was gained. These changes led to the specific expression of CGB in the placenta and its decrease in the pituitary. Recent findings on gonadotrophins led to an extended model for the sequence of events in the evolution of the CGB gene in primates and its tissue-specific expression.

Assessment of the biopotency of follitropin alfa and lutropin alfa combined in one injection: a comparative trial in Sprague-Dawley rats

BACKGROUND

The current study was designed to determine if follitropin alfa (recombinant human follicle-stimulating hormone; r-hFSH) and lutropin alfa (recombinant human luteinizing hormone; r-hLH) biopotencies were unchanged by reconstituting in sterile water for injection and mixing prior to injection.

METHODS

The biopotencies of r-hFSH and r-hLH were determined following injection of female Sprague-Dawley rats with a mixture of follitropin alfa revised formulation female (RFF) and lutropin alfa (1:1, r-hFSH:r-hLH). Biopotencies of follitropin alfa RFF and lutropin alfa were measured using ovarian weight and ascorbic acid depletion assays, respectively, and compared with a reference standard. Stock mixtures of follitropin alfa RFF and lutropin alfa (1:1) were prepared within 1 h prior to each respective assay's injection and stored at 6 +/- 2 degrees C. Separate low dose (follitropin alfa RFF 1.5 IU/rat, lutropin alfa 2 IU/rat) and high dose (follitropin alfa RFF 3 IU/rat, lutropin alfa 8 IU/rat) treatments were prepared from stock mixtures or individual solutions by diluting with 0.22% bovine serum albumin saline solution and injected within 1 h of preparation. The main outcome measures were ovarian weight and ovarian ascorbic acid depletion.

RESULTS

FSH bioactivities were similar (p > 0.10) between the individual follitropin alfa RFF test solution (84.2 IU) and follitropin alfa RFF/lutropin alfa (87.6 IU) mixtures prepared within 1 h of injection and stored at 6 +/- 2 degrees C. LH bioactivities were similar (p > 0.10) between lutropin alfa (94.7 IU) test solution and lutropin alfa/follitropin alfa RFF (85.3 IU) mixtures prepared within 1 h of injection and stored at 6 +/- 2 degrees C for not more than 1 h prior to injection.

CONCLUSION

Mixing follitropin alfa RFF and lutropin alfa did not alter the bioactivity of either FSH or LH.

Gonadotropins in doping: pharmacological basis and detection of illicit use

Parenteral administration of human chorionic gonadotropin (hCG) or luteinizing hormone (LH) stimulates the production of testosterone in males and these gonadotropins can therefore be used by athletes to enhance muscle strength. However, they are more expensive and less efficient than testosterone and anabolic steroids. Therefore their main use is probably to stimulate gonadal testosterone production during and after self-administration of testosterone or anabolic steroids. A positive effect of hCG on muscle strength has not been demonstrated in women and elevated concentrations of hCG in females are often caused by pregnancy. The use of gonadotropins is therefore prohibited only in males but not in females. HCG occurs at low but measurable concentrations in plasma and urine of healthy males and can be measured by sensitive methods. However, the characteristics of the method to be used for doping control have not been defined. Virtually all commercially available hCG assays have been designed for determination of hCG in serum rather than urine, which is used for doping control. Methods based on mass spectrometric detection of fragments derived from hCG extracted from urine by immunoadsorption have been developed but their suitability for doping control remains to be determined. The concentrations of LH in serum and urine are variable and more then 10-fold higher than those hCG. It is therefore difficult to detect illicit use of LH. The characteristics and reference values for hCG and LH assays used in doping control and the cutoff values need to be defined.

Bioequivalence of recombinant human FSH and recombinant human LH in a fixed 2:1 combination: two phase I, randomised, crossover studies

OBJECTIVES

To assess bioequivalence of recombinant human follicle stimulating hormone (r-hFSH, follitropin alfa) and recombinant human luteinising hormone (r-hLH, lutropin alfa) in a fixed 2:1 combination (Pergoveris) compared with injection of each of the hormones separately.

RESEARCH DESIGN AND METHODS

Two, two-way crossover, phase I studies in healthy female volunteers after gonadotrophin-releasing hormone agonist down-regulation. Volunteers were randomised to the order in which they received subcutaneous injections. In the r-hFSH study, volunteers received one injection of r-hFSH (300 IU) and one of r-hFSH (300 IU)/r-hLH (150 IU) > or = 7 days apart; in the r-hLH study they received r-hLH (450 IU) and r-hFSH (900 IU)/r-hLH (450 IU) > 21 days apart.

MAIN OUTCOME MEASURES

The serum concentration-time profiles of FSH in the r-hFSH study and LH in the r-hLH study from zero to the last measurable concentration (AUC(0-last)) and the peak FSH/LH serum concentrations (C(max)) were assessed by non-compartmental analysis. The pre-defined range for bioequivalence was 0.8-1.25 for 90% confidence intervals (CI) of the ratio (fixed combination/single gonadotrophin) of the mean for each pharmacokinetic parameter.

RESULTS

Bioequivalence criteria were met for the r-hFSH study (n = 34) for C(max) (ratio of means 1.0024, 90% confidence interval (CI) 0.9611-1.0454) and AUC(0-last) (ratio of means 1.0167, 90% CI 0.9933-1.0407), and for the r-hLH study (n = 63) for C(max) (ratio of means 0.9687, 90% CI 0.9194-1.0207) and AUC(0-last) (ratio of means 0.9753, 90% CI 0.8990-1.0581). In the r-hFSH study, 20 adverse events (AEs) were reported after injection of r-hFSH and 20 after r-hLH/r-hFSH. In the r-hLH study, 179 AEs were reported after injection of r-hLH and 193 after the fixed-dose combination. Across both studies, headache was the most commonly reported AE. No serious AEs occurred.

CONCLUSIONS

These studies demonstrated bioequivalence between r-hFSH and r-hLH administered alone or in fixed 2:1 combination. The 2:1 combination of follitropin alfa and lutropin alfa allows administration of both recombinant gonadotrophins in a single injection.

The role of aromatase inhibitors in ameliorating deleterious effects of ovarian stimulation on outcome of infertility treatment

Clinical utilization of ovulation stimulation to facilitate the ability of a couple to conceive has not only provided a valuable therapeutic approach, but has also yielded extensive information on the physiology of ovarian follicular recruitment, endometrial receptivity and early embryo competency. One of the consequences of the use of fertility enhancing agents for ovarian stimulation has been the creation of a hyperestrogenic state, which may influence each of these parameters. Use of aromatase inhibitors reduces hyperestrogenism inevitably attained during ovarian stimulation. In addition, the adjunct use of aromatase inhibitors during ovarian stimulation reduces amount of gonadotropins required for optimum stimulation. The unique approach of reducing hyperestrogenism, as well as lowering amount of gonadotropins without affecting the number of mature ovarian follicles is an exciting strategy that could result in improvement in the treatment outcome by ameliorating the deleterious effects of the ovarian stimulation on follicular development, endometrial receptivity, as well as oocyte and embryo quality.

Hormonal effects in infants conceived by assisted reproductive technology

OBJECTIVE

The purpose of this report is to describe 7 infants conceived by assisted reproductive technology (ART) who presented with breast development and/or pubic hair. The clinical presentation in these infants raises awareness that an altered intrauterine hormonal milieu may impact the fetal and infant stages of children conceived by ART.

METHODS

Between May 2001 and April 2004, 7 children between the ages of 5 and 21 months conceived by ART were referred by their pediatricians to the Division of Pediatric Endocrinology at the New York University School of Medicine for evaluation of possible precocious puberty. Patients were evaluated for the possibility of centrally mediated precocious puberty and pseudoprecocious puberty, with a possible ovarian or adrenal origin.

RESULTS

Endocrine evaluation in all patients indicated sex-steroid and hormone levels in the prepubertal range; pelvic sonography confirmed prepubertal ovaries with unstimulated uteri. Clinical follow-up of our patients thus far has not revealed progression of breast development, pubarche, or elevation in sex steroids.

CONCLUSIONS

It is well established that the developing endocrine system in the fetus and maturation of endocrine-control systems are influenced by hormone concentrations in the fetus. Whether ART alters the intrauterine hormonal milieu for the growing fetus conceived by ART is as yet unknown and is an area of ongoing investigation. Patients conceived through ART, including our patients who presented with hormonal manifestations, will need to be monitored throughout childhood and into adolescence and adulthood to determine if any perturbation exists on the timing of puberty and later fertility.

Treatment of female infertility with recombinant human luteinising hormone: is there a benefit over other available drugs?

This manuscript reviews the role of recombinant human luteinising hormone (rhLH) as a therapeutic drug in ovarian stimulation for assisted reproductive technology (ART) and ovulation induction. For this purpose, the role of LH during the follicular phase and during the ovulatory surge, along with the role of human chorionic gonadotropin (hCG) as a surrogate LH, is reviewed and compared to the results available with the new rhLH formulation. The use of rhLH was found to be safe and highly effective given during the follicular phase and to mimic an endogenous LH surge. The availability of both LH and follicle stimulating hormone (FSH) as separate recombinant preparations enables physicians to adjust the doses of each gonadotropin to the individual patient according to the 'therapeutic window' concept for each drug to maximise the success of ovarian stimulation.

Evaluation of two doses of recombinant luteinizing hormone supplementation in an unselected group of women undergoing follicular stimulation for in vitro fertilization

OBJECTIVE

To evaluate the efficacy of two doses of recombinant (r)LH, 75 IU (recommended) or 37.5 IU, for follicular stimulation and outcomes in a randomized cohort of IVF patients.

DESIGN

Randomized, prospective analysis.

SETTING

Private hospital incorporating an established IVF center.

PATIENT(S)

Women undergoing IVF who had a body mass index >18 or <35 and no abnormal karyotype, anovulation, oligomenorrhea, or any known endocrinopathy/illness.

INTERVENTION(S)

Pituitary desensitization was achieved with triptorelin (0.1 mg SC), and gonadotropin stimulation was performed with either rFSH alone (group A) or in combination with rLH in one of two doses: 37.5 IU (group B) or 75 IU (group C), daily.

MAIN OUTCOME MEASURE(S)

A range of endocrinologic, embryologic, clinical, and outcome parameters were evaluated.

RESULT(S)

With rLH supplementation there was a significant increase in the incidence of implantation (9% for rFSH only [group A] vs. 11% and 16% with 37.5 IU rLH and 75.0 IU rLH [groups B and C], respectively) and clinical pregnancy (19% vs. 23% and 31%) (P<.01 and P<.04, respectively), whereas there was no difference in the multiple pregnancy rates. There was a significant (P<.001) increase in the total units of rFSH used in proportion to the amount of rLH supplementation (2,645 U vs. 3,475 U and 3,681 U) and in the level of peripheral E(2) on the day of hCG administration (1,049 pg/mL vs. 1,640 pg/mL and 1,226 pg/mL) (P<.001). There was no significant between difference in mean age, numbers of oocytes recovered, basal and downregulation hormone levels, or the incidence of fertilization in the absence or presence of rLH supplementation, but a higher incidence of grade 1 to 2 embryos was observed when rLH was supplemented.

CONCLUSION(S)

After pituitary desensitization, there was an increase in the incidence of implantation, clinical pregnancy, and delivery rates in patients stimulated with rFSH supplemented with rLH.

Randomized trial to compare the effect of recombinant human FSH (follitropin alfa) with or without recombinant human LH in women undergoing assisted reproduction treatment

Women undergoing intracytoplasmic sperm injection (ICSI) for male factor infertility were randomly assigned to receive ovarian stimulation in a long agonist protocol with a combination of recombinant human FSH (r-hFSH; Gonal-F) and recombinant human LH (r-hLH; Luveris) (n = 212) starting on day 6 of FSH stimulation until human chorionic gonadotrophin (HCG) at a daily fixed dose of 150 IU r-hLH, or with r-hFSH alone (n = 219). There was no significant difference in the number of metaphase II oocytes retrieved (10.3 versus 10.4) in patients treated with r-hFSH and r-hLH versus r-hFSH alone; however, more embryos were transferred in the LH-supplemented group (2.9 versus 2.8, P = 0.037). Overall, the implantation rates were 22.9 versus 27.0% in patients treated with r-hFSH and r-hLH versus with r-hFSH alone respectively (NS). The respective numbers of MII oocytes retrieved in patients <35 or >or=35 years were 11 versus 8.3 (P = 0.010) for patients treated with r-hFSH alone, and 10.7 versus 9.3 (NS) for those given supplemental r-hLH (150 IU) from day 6. Implantation rates in patients <35 years treated with r-hFSH were higher (30.7%) than those receiving r-hFSH and r-hLH, (23.5%) (P = 0.068). In patients >or=35 years, the implantation rates were 21.7% for those patients supplemented with 150 IU r-hLH from day 6 of stimulation versus 15.7% when treated with FSH alone (NS). Younger patients therefore do not seem to benefit from an LH-supplemented ovarian stimulation protocol, but women >or=35 years undergoing assisted reproduction may benefit from using r-hLH in addition to r-hFSH.

Biochemical and functional aspects of gonadotrophin-releasing hormone and gonadotrophins

Reproductive function in mammals is governed by the hypothalamic-pituitary-gonadal axis, which conforms a functional unit. Sexual maturation and the subsequent development of reproductive competence depend on the precise and coordinated function of this axis. The components of the reproductive axis communicate each other through endocrine signals. The hypothalamus synthesizes gonadotrophin-releasing hormone or GnRH, which in turn stimulates synthesis and secretion of the pituitary gonadotrophins, follicle-stimulating hormone (FSH) and luteinizing hormone (LH). The ovarian follicles and the interstitial and Sertoli cells of the testis are the targets for these pituitary signals. Under gonadotrophic stimulation, the gonads produce and secrete several steroid and non-steroid (polypeptide) factors, which in turn regulate in different ways the function of the hypothalamic-pituitary axis. An episodic and pulsatile mode of secretion of hormonal signals characterize (as in other endocrine systems) the function of the reproductive axis, particularly that of the hypothalamic-pituitary unit. The target cell response, and consequently the harmonic function of the corresponding gland, will depend on the adequate dynamics of this pulsatile secretion. The function of each component of the reproductive axis is strongly influenced by locally-produced signals acting either in a paracrine or autocrine manner; these particular signals represent fine-tuning regulation systems that eventually amplify or restrain the magnitude of response to a particular endocrine signal, providing additional mechanisms for tissue homeostasis and a better functional plasticity of the target gland. The design and rational use of novel therapeutic strategies for an optimal exogenously-controlled reproductive function largely depend on the detailed knowledge of the hypothalamic-pituitary-gonadal axis function and the structure and mechanism of action of those factors and signals involved in its regulation.

[Ovarian stimulation: is exogenous LH necessary in all patients?]

FSH and LH play an essential but different role in the growth of ovarian follicles during the cycle. In stimulation protocols, good follicular development is obtained in most patients treated with FSH alone whereas the role of LH is more complex and controversial. Clinical and pre-clinical studies have shown that optimal follicular development is obtain if (i) exposure to endogenous and/or exogenous LH is sufficient ("threshold" concept) and (ii) exposure to LH is not excessive ("ceiling" concept). The recombinant luteinizing hormone (r-hLH, Luveris) is the only available stand-alone preparation of LH. Its characteristics are a high specific activity, the absence of undesirable proteins and an excellent batch to batch consistency. Luveris is indicated in association with FSH for stimulating follicular development in LH and FSH deficient women (defined by an endogenous LH level < 1.2 UI/l). In this subgroup of patients, the therapeutic benefit of exogenous LH at a daily dose of 75 IU is only observed when endogenous serum LH is below than 1.2 IU/l: LH threshold concept. In ART, the combination of exogenous LH at a daily dose from 75 to 150 IU and recombinant FSH improved the ovarian stimulation results only in a minority of patients (5 to 17%). On the opposite, studies conducted in OMS I and II patients showed that high doses of exogenous LH lead to atresia of secondary follicles. So, a daily dose of exogenous LH greater than 225 IU had a deleterious effect on follicular growth: LH ceiling concept.

Human recombinant luteinizing hormone is as effective as, but safer than, urinary human chorionic gonadotropin in inducing final follicular maturation and ovulation in in vitro fertilization procedures: results of a multicenter double-blind study

In a prospective, comparative, dose-finding study, the minimal effective dose of recombinant human LH (rhLH) required to induce final follicular maturation and early luteinization in patients undergoing in vitro fertilization and embryo transfer was determined. In addition, the efficacy and safety of rhLH were compared with urinary human CG (u-hCG). A total of 259 infertile women, aged 18-39 yr, were enrolled in the study. After pituitary desensitization using a GnRH agonist, rhFSH was administered for ovarian stimulation. Patients then received either rhLH or u-hCG to achieve final follicular maturation. The doses of rhLH administered were 5,000, 15,000, 30,000, or 15,000 + 10,000 IU (second injection administered 3 days after the first injection; 129 patients), and those of u-hCG were consistently 5,000 IU (121 patients). Ovum pick-up was performed 34--38 h after rhLH or u-hCG injection. After fertilization in vitro, up to three embryos were replaced in the uterine cavity. The numbers of oocytes retrieved after u-hCG or rhLH administration were not significantly different between the four different doses of rhLH, when compared with each corresponding u-hCG group, nor when compared with the pool of all u-hCG groups. Similarly, there were no statistically significant differences in: the number of oocytes retrieved per follicle with a diameter of over 10 mm on the day of u-hCG or rhLH administration; the number of patients with at least one oocyte retrieved; oocyte nuclear maturity; oocyte potential for fertilization; the number of embryos; the number of total, biochemical, and clinical pregnancies; and the embryo implantation rate. However, in many of these parameters, the lowest dose of rhLH seemed suboptimal when compared with the higher dose. In terms of safety, rhLH was well tolerated at a dose of up to 30,000 IU. Moderate ovarian hyperstimulation syndrome (OHSS) was reported in 12.4% of patients who received u-hCG and 12.0% of patients who received two injections of rhLH. No moderate or severe OHSS was reported in patients who received a single dose of rhLH up to 30,000 IU. The results show that a single dose of rhLH is effective in inducing final follicular maturation and early luteinization in in vitro fertilization and embryo transfer patients and is comparable with 5,000 IU u-hCG. A single dose of rhLH results in a highly significant reduction in OHSS compared with hCG. The dose of rhLH giving the highest efficacy to safety ratio was between 15,000 and 30,000 IU.