The effect of a single escalating dose of long-acting recombinant human follicle-stimulating hormone Fc fusion protein (KN015) on healthy, pituitary-suppressed women: first-in-human and randomized study on its pharmacokinetics, pharmacodynamics, and tolerability.

OBJECTIVE: KN015 is a long-acting, recombinant human follicle-stimulating hormone Fc fusion protein that induces follicle development. This first-in-human study evaluated the effect of KN015 on healthy, pituitary-suppressed women and examined its pharmacokinetics, pharmacodynamics, and tolerability. METHODS: This phase I study was a double-blind, randomized, and placebo-controlled design with a single ascending dose (20, 40, and 60 µg, respectively). RESULTS: After subcutaneous administration of a single dose, the maximum serum KN015 concentrations reached 1.57, 2.78, and 3.62 ng/mL, respectively, after baseline adjustment. Over this dose range, the median Tmax occurred at 240-312 h, and the half-life (t½) was 752-1160 h. Dose proportionality was shown across the studied dose range. In most subjects, follicular growth was observed, and the number and diameter of the follicles increased with an increasing dose. In the 40-µg and 60-µg groups, the mean numbers of follicles with a diameter of ≥17 mm were 3 and 4, respectively. There was no significant difference in adverse events between the KN015 and placebo groups. KN015 antibody was not detected in any of the dosage groups. CONCLUSION: The administration of a single ascending dose of KN015 was tolerated and able to induce follicular growth. TRIAL REGISTRATION: This trial is registered at the Chinese Clinical Trials website (http://www.chinadrugtrials.org.cn/index.html # CTR20160741) and ClinicalTrials.gov (https://clinicaltrials.gov/ # NCT03192527).

New Human Follitropin Preparations: How Glycan Structural Differences May Affect Biochemical and Biological Function and Clinical Effect.

It is well accepted that pituitary follitropin is secreted into the circulation as a mixture of variants, which differ not in primary structure but rather at the level of glycosylation. These glycosidic forms vary in the number of glycosylation sites filled, complexity of glycosidic chains, and sialylation and sulfation. It is generally agreed that high sialylation, 2,3 sialic acid capping of terminal N-acetyl galactosamine or galactose leads to longer circulating half-life, by blocking binding of asialoglycoprotein receptor (ASGPR) in the liver. In contrast, 2,6 sialic acid found in humans does not prevent recognition of galactose and N-acetyl galactosamine by ASGPR. Few studies on clinical outcomes comparing differences in sialylation of follitropin found in commercially available preparations are available. Thus, there is a clear need for a consortium of open data to address this unmet need. Recently, FSH glycosylation, primarily on the ß-subunit, which varies as women age, has emerged as a key modifier of follitropin action, with profound biological effects in vivo in animal models. To date, limited information of recombinant follitropin hormone preparations is available. Thus, most of the studies with FSH that is well characterized biochemically have been done in vitro, with engineered non gonadal host cells bearing recombinant receptors or in animal models. Since limited studies in human granulosa cells are available, a question is whether structural differences in glycosylation in commercially available follitropin affects biological function and clinical effect in humans. The presence of fucose, for example, has not been studied greatly even though, in the case of antibody therapy it has been shown to have a large effect on antibody targeting. This review on glycosidic variability of follitropin from the biochemical/structural point of view reflects on this question and presents an assessment in the context of available published data. If clinical differences are to be expected or not, the readers will have a better understanding of the evidence for and limitations of such expectations.

Population PK-PD-PD Modeling of Recombinant Follicle Stimulating Hormone in In Vitro Fertilization/Intracytoplasmic Sperm Injection: Implications on Dosing and Timing of Gonadotrophin Therapy.

This study aimed to characterize an interactive and clinically applicable population pharmacokinetic-pharmacodynamic-pharmacodynamic (PK-PD-PD) model describing follicle-stimulating hormone (FSH)-inhibin B-oocyte relationship in women undergoing assisted reproduction with in vitro fertilization (IVF) or intracytoplasmic sperm injection (ICSI). The study was a prospective analysis of 25 healthy women undergoing IVF/ICSI using gonadotropin-releasing hormone (GnRH) antagonist protocol. The developed model used the FSH PK profiles to predict both inhibin B (first PD end point) and oocyte retrieval (second PD end point). The modeling framework involved 2 stages. First, the FSH-inhibin B model was developed by the simultaneous approach and applied to estimate the individual area under the inhibin B-time curve (AUCInhb ) at the end of stimulation cycles that varied in length in each woman. In the second stage, the estimated AUCInhb was introduced as a link covariate to predict oocyte retrieval and response category. The population FSH-inhibin B model was described as 3 submodels; PK (exogenous), endogenous, and inhibin B PD models. Weight was the main determinant of both endogenous and exogenous FSH exposures. GnRH antagonist therapy was a significant time-varying covariate when tested against the endogenous FSH production rate (P < .001). AUCInhb could be predicted with women's age and weight. Log-transformed AUCInhb was a significant covariate when tested against oocyte retrieval (P < .001). Simulations concluded a target AUCInhb of 144-303 ng·h/mL for optimal ovarian response. The GnRH antagonist was better started on day 7 of the cycle. Covariate-based dosing suggests lower recombinant follicle-stimulating hormone requirements in a thin and/or young population. An interactive web application "GonadGuide" was developed to facilitate the application in clinical practice.

Preparation, characterization and application of long-acting FSH analogs for assisted reproduction.

Assisted reproduction technologies are widely used in humans and domestic animals and often include follicle stimulating hormone (FSH) in the protocol. One limitation with most of the available FSH preparations is the relative short half-life in the circulation that dictates multiple daily injections for the desired follicle development and superovulation. The development of bioactive long-acting structurally modified FSH analogs is desirable for human and veterinary use. In addition, optimal preparations and/or formulations are expected to improve the regimen and efficiency of the treatment. This review briefly describes the approaches that have been explored to extend the half-life of FSH in the circulation. These include strategies to increase the mass and/or charge of FSH and to prevent the dissociation of the hormone to inactive subunits components. Most of these strategies, except one that led to a registered drug (Elonva) indicated for controlled ovarian stimulation protocols in humans, are still in experimental stage.

The isoflavone daidzein directly affects porcine ovarian cell functions and modifies the effect of follicle-stimulating hormone.

The key biological active molecule of soya is the isoflavone daidzein, which possesses phytoestrogenic activity. The direct effect of soya and daidzein on ovarian cell functions is not known. This study examined the effect of daidzein on basic porcine ovarian granulosa cell functions and the response to follicle-stimulating hormone (FSH). We studied the effects of daidzein (0, 1, 10 and 100 µm), FSH (0, 0.01, 0.1, 1 IU/ml) and combinations of FSH (0, 0.01, 0.1, 1 IU/ml) + daidzein (50 µm) on proliferation, apoptosis and hormone release from cultured porcine ovarian granulosa cells and ovarian follicles. The expression of a proliferation-related peptide (PCNA) and an apoptosis-related peptide (Bax) was analysed using immunocytochemistry. The release of progesterone (P4) and testosterone (T) was detected using EIA. Leptin output was analysed using RIA. Daidzein administration increased granulosa cell proliferation, apoptosis and T and leptin release but inhibited P4 output. Daidzein also increased T release and decreased P4 release from cultured ovarian follicles. Follicle-stimulating hormone stimulated granulosa cell proliferation, apoptosis and P4, T and leptin release. The addition of daidzein promoted FSH-stimulated apoptosis (but not proliferation) but suppressed FSH-stimulated P4, T and leptin release. Our observations of FSH action confirm previous data on the stimulatory effect of FSH on ovarian cell proliferation, apoptosis and steroidogenesis and demonstrate for the first time the involvement of FSH in the upregulation of ovarian leptin release. Our observations of daidzein effects demonstrated for the first time that this soya isoflavone affected basic ovarian cell functions (proliferation, apoptosis and hormones release) and modified the effects of FSH. Daidzein promoted FSH action on ovarian cell proliferation and apoptosis and suppressed, and even inverted, FSH action on hormone release. The direct action of daidzein on basic ovarian cell functions and the ability of these cells to respond to FSH indicate the potential influence of soya-containing diets on female reproductive processes via direct action on the ovary.

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 (AUCt) 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 (AUCτ) of 322.59 ± 57.92 IU/L·h, which was similar to the mean AUCt 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.

Effects of AY9944 A-7 on gonadotropin-induced meiotic resumption of oocytes and development of parthenogenetic embryos in sheep.

Follicular fluid meiosis-activating sterol (FF-MAS), an intermediate in the cholesterol biosynthetic pathway, has been identified as a compound that induces the resumption of meiosis in mammalian oocyte. Follicular fluid meiosis-activating sterol is converted to testis meiosis-activating sterol by a sterol Δ14-reductase. An inhibitor of Δ14-reductase and Δ7-reductase, AY9944 A-7, causes accumulation of FF-MAS by inhibiting its metabolism. The objective of this research was to investigate the specific contribution of AY9944 A-7 on gonadotropin-induced meiotic resumption and its interactive effects with FSH or LH on meiotic maturation of oocytes and preimplantation development of parthenogenetic embryo in sheep by addition of AY9944 A-7 during IVM to cause accumulation of FF-MAS. First, ovine cumulus-oocyte complexes (COCs) were cultured in the presence of FSH (10 µg/mL), LH (10 µg/mL), AY9944 A-7 (20 µmol/L), FSH (10 µg/mL)+AY9944 A-7 (20 µmol/L), or LH (10 µg/ml) + AY9944 A-7 (20 µmol/L) with an inhibitor hypoxanthine (Hx) to prevent spontaneous meiosis of oocytes. The resumption of meiosis was assessed by the frequency of germinal vesicle breakdown and the first polar body (PBI) extrusion. The kinetics of gonadotropin and AY9944 A-7-induced meiotic resumption in vitro was also evaluated in the study. The numbers of oocytes resuming meiosis and undergoing germinal vesicle breakdown were counted after the COCs were cultured for 2, 4, 8, 12, 16, 20, and 24 hours. Matured oocytes extruding PBI were selected for parthenogenetic activation, and the percentages developing to the two-cell stage and blastocyst stage were recorded as indicators of parthenogenetic embryo developmental competence. It was observed that FSH could induce the resumption of meiosis of ovine COCs cultured in the presence of Hx, but LH could not. AY9944 A-7 had a synergistic effect with FSH on nuclear maturation and developmental competence of embryos produced by parthenogenetic activation, whereas it had no added advantage on LH action. However, the kinetics of meiotic resumption after AY9944 A-7 stimulation was remarkably delayed when compared with FSH-induced maturation. In conclusion, the current study suggested that AY9944 A-7 supplementation in IVM medium optimized the beneficial effects of FSH on meiotic maturation of ovine oocytes and subsequent developmental competence of embryos produced by parthenogenetic activation. This work had important potential for developing a novel technique in IVM of ovine oocytes.

Different pharmacokinetic and pharmacodynamic properties of recombinant follicle-stimulating hormone (rFSH) derived from a human cell line compared with rFSH from a non-human cell line.

Pharmacokinetic and pharmacodynamic properties of a novel recombinant follicle-stimulating hormone (rFSH) preparation (FE 999049), expressed by a human cell line (PER.C6), was compared with an rFSH preparation (follitropin α) expressed by a Chinese hamster ovary (CHO) cell line in healthy pituitary-suppressed women. Following single intravenous administration of 225 IU (Steelman-Pohley assay), the clearance was lower, 0.31 versus 0.44 L/h, for FE 999049 than for follitropin α. Likewise, the apparent clearance after repeated daily subcutaneous administrations was lower, 0.58 versus 0.99 L/h, and AUC and C(max) higher, 1.7- and 1.6-fold. The absolute bioavailability after a single subcutaneous dose of 450 IU was similar for both preparations, 60-65%. After repeated subcutaneous administration the elimination half-life was approximately 30 and 24 hours for FE 999049 and follitropin α. The ovarian responses by number of follicles and serum concentrations of inhibin B and estradiol, were higher with FE 999049 than with follitropin α, AUC and C(max) for the two latter being >1.6-fold greater with FE 999049 than with follitropin α. These results indicate that administration of equal doses of FE 999049, expressed in a human cell line, and follitropin α, expressed in a CHO cell line, display different pharmacokinetic and pharmacodynamic properties in humans.

Superoxide dismutase-loaded biodegradable nanoparticles targeted with a follicle-stimulating hormone peptide protect Sertoli cells from oxidative stress.

OBJECTIVE: To evaluate targeted superoxide dismutase (SOD)-loaded biodegradable nanoparticles' (NPs) ability to protect Sertoli cells from hydrogen peroxide (H2O2)-induced oxidative stress. DESIGN: Cell culture controlled experimental study. SETTING: Research laboratory. CELLS: Mouse testis Sertoli cells (TM4). INTERVENTIONS: Sertoli cells were exposed to 0-200 µg/mL plain media, unconjugated NPs, or FSH peptide-conjugated NPs for 2 or 24 hours to assess uptake. Next, Sertoli cells were exposed to 0-50 mmol H2O2 with 0-1 mg/mL unconjugated SOD-loaded NPs, FSH-conjugated SOD-loaded NPs, or equivalent units of SOD in solution as a control for 2-6 hours to assess influence on cell survival after oxidative stress. MAIN OUTCOME MEASURE(S): Cell viability, flow cytometry, and microscopy. RESULT(S): FSH peptide targeting improved uptake of NPs by Sertoli cells. FSH-conjugated SOD-NPs significantly protected Sertoli cells at 6 hours of H2O2--induced oxidative stress, with 100% survival with FSH-conjugated SOD-NPs compared with unconjugated SOD-NPs (45%) or SOD in solution (36%). CONCLUSION(S): Conjugation of NPs with FSH peptide improves cellular uptake and survival when SOD-loaded NPs are coincubated with Sertoli cells undergoing oxidative stress. This study represents a step toward developing NPs for the targeted treatment of testicular oxidative stress.

Abdominal mesotherapy injection extended the absorption of follicle-stimulating hormone.

Abdominal mesotherapy injection of recombinant human FSH (rhFSH) was well tolerated with increased net absorption (AUC0-∞ 4,655.3 IU·h/L and t1/2 247.6 h) up to 360 hours compared with those of 120 hours (AUC0-∞ 1,915.7 IU·h/L and t1/2 101.8 h). The extended absorption of rhFSH suggests that abdominal mesotherapy injection mode be considered for future administration of rhFSH in controlled ovarian hyperstimulation.

Pharmacokinetics and follicular dynamics of corifollitropin alfa versus recombinant FSH during ovarian stimulation for IVF.

A single injection of corifollitropin alfa can replace seven daily injections of recombinant FSH (rFSH) using a gonadotrophin-releasing hormone antagonist protocol in ovarian stimulation prior to IVF or intracytoplasmic sperm injection. This double-blind randomized controlled trial assessed the pharmacokinetics and pharmacodynamics of 150µg corifollitropin alfa versus daily 200IU rFSH in 1509 patients. Comparative analyses were performed on serum concentrations of FSH immunoreactivity (pharmacokinetics), and the number and size of growing follicles, and inhibin B and oestradiol concentrations as biomarkers of ovarian response (pharmacodynamics). The rate of follicular development was similar in both treatment groups. By stimulation day 8, 33% of patients treated with corifollitropin alfa reached the criterion for human chorionic gonadotrophin (HCG) injection. The number of follicles ⩾11mm was slightly higher after corifollitropin alfa compared with daily rFSH at stimulation day 8 (difference, 1.2; 95% confidence interval (CI) 0.5-1.8; P<0.01) and on the day of HCG injection (difference, 2.1; 95% CI 1.4-2.8; P<0.01). The rise of inhibin B and oestradiol concentrations was similar in both treatment groups. Although the pharmacokinetics of corifollitropin alfa and rFSH are quite different their pharmacodynamic profiles at the dosages used are similar. A single injection of corifollitropin alfa can replace seven daily injections of recombinant FSH (rFSH) using a gonadotrophin-releasing hormone antagonist protocol in ovarian stimulation prior to IVF or intracytoplasmic sperm injection. The objective of this study was to compare the pharmacokinetics and pharmacodynamics of corifollitropin alfa versus daily rFSH. A total of 1509 patients were randomized in a double-blind, controlled trial to either a single injection of 150µg corifollitropin alfa or to daily injections of 200IU rFSH for the first 7 days of ovarian stimulation. Serum levels of FSH immunoreactivity were analysed (pharmacokinetic analysis), together with the number and size of growing follicles and serum inhibin B and oestradiol concentrations as biomarkers of the ovarian response (pharmacodynamic analysis). Serum FSH immunoreactivity levels were higher up to stimulation day 5 for corifollitropin alfa compared with the daily rFSH regimen but were similar from day 8 onwards, when patients started rFSH if the criteria for human chorionic gonadotrophin were not yet reached. Corifollitropin alfa treatment resulted in a similar growth rate of follicles though a slightly higher number of follicles were recruited compared with daily rFSH. It is concluded that the pharmacokinetics of corifollitropin alfa and rFSH are quite different but their induced pharmacodynamic effects at the dosages used are similar.

Recombinant human follicular stimulating hormone and recombinant human luteinizing hormone in a 2:1 ratio combination. Pharmacological characteristics and clinical applications.

IMPORTANCE OF THE FIELD: A new fixed combination of recombinant human follicle stimulating hormone (r-hFSH) and recombinant human luteinizing hormone (r-hLH) at a 2:1 ratio has been recently developed to induce ovulation in patients with hypogonadotrophic hypogonadism. Whether or not this compound is useful for controlled ovarian stimulation for in vitro fertilization is still a matter of debate. AREAS COVERED IN THIS REVIEW: Description of pharmacological and clinical aspects of this new product, through the analysis of the Phase I, II and II trials and post-marketing clinical randomized trials, performed since the initial assays in 1998 to nowadays. WHAT THE READER WILL GAIN: After reading this review the reader will understand the pharmacological aspects of this new compound, in terms of efficacy and safety, and will have an update of the potential role of r-LH administration in controlled ovarian stimulation for in vitro fertilization. TAKE HOME MESSAGE: The 2:1 combination of r-hFSH and r-hLH has been seen as an optimum preparation in terms of safety and clinical efficacy in hypogonatrophic hypogonadism patients. Its use in ovarian stimulation for IVF remains controversial, as the target population that may receive a benefit of it is not well defined.

The absorption and uptake of recombinant human follicle-stimulating hormone through vaginal subcutaneous injections--a pharmacokinetic study.

BACKGROUND: Follicle stimulating hormone (FSH) has been routinely used for ovulation induction. Because of rapid clearance of the hormone, FSH is commonly administered by daily intramuscular or subcutaneous injections in in-vitro fertilization (IVF). To reduce the number of visits to the clinic, an intermittent vaginal injection of rhFSH every 3 days employing the concepts of mesotherapy and uterine first-pass effect was invented and has successfully been applied in women receiving IVF treatment. This study was designed to monitor the pharmacokinetic pattern of rhFSH administered vaginally. METHODS: Twelve healthy women with regular ovulatory cycles were recruited. All volunteers received gonadotrophin-releasing hormone agonist to suppress pituitary function and were assigned to receive single dose recombinant human FSH (rhFSH, Puregon 300) either using conventional abdominal subcutaneous injection or vaginal subcutaneous injection in a randomized cross-over study. Serum samples were collected at pre- scheduled time intervals after injections of rhFSH to determine immunoreactive FSH levels. Pharmacokinetic parameters characterizing rate [maximal plasma concentrations (Cmax) and time of maximal plasma concentrations (tmax)] and extent [area under the plasma concentration-time curve (AUC) and clearance] of absorption of rhFSH were compared. RESULTS: Vaginal injection of rhFSH was well tolerated and no drug-related adverse reaction was noted. Our analysis revealed that tmax was significantly earlier (mean 6.67 versus 13.33 hours) and Cmax was significantly higher (mean 17.77 versus 13.96 IU/L) in vaginal versus abdominal injections. The AUC(0-infinity) was 1640 versus 1134 IU hour/L in vaginal and abdominal injections, respectively. Smaller plasma elimination rate constant (0.011 versus 0.016 hour-1), longer mean residence time (106.58 versus 70.47 hours), and slower total body clearance (292.2 versus 400.1 mL/hour) were also found in vaginal injection. CONCLUSION: The vaginal injection mode elicited a rapid and highly extended absorption of rhFSH injected compared to conventional abdominal injection. These data indicate that the rate and extent of FSH absorption from the injection site can vary depending on the route of the FSH administration.

Recombinant FSH in the treatment of oligozoospermia.

BACKGROUND: FSH plays a crucial role in human reproduction. Treatment with gonadotrophins has been shown to be effective in males affected by hypogonadotrophic hypogonadism. The success of this treatment has brought about the utilization of the same therapy in infertile oligozoospermic subjects, aimed at obtaining increased sperm count. This physiological role in spermatogenesis has induced various attempts to treat idiopathic oligozoospermic men with FSH, often inducing the restoration of normal spermatogenesis and spontaneous pregnancy. OBJECTIVE: To evaluate clinical efficacy of recombinant FSH in male infertility. METHODS: Evaluation of pharmacokinetic, pharmacodynamic properties, efficacy and safety of this hormone preparation, on the basis of the data published in literature. CONCLUSIONS: Recombinant FSH is effective, safe and well tolerated. Treatment with this hormone may represent a valid tool for infertile men. However it should be performed on selected patients utilizing some predictive parameters able to identify a priori responder subjects with high probability.

Advances in recombinant DNA technology: corifollitropin alfa, a hybrid molecule with sustained follicle-stimulating activity and reduced injection frequency.

BACKGROUND: Recombinant DNA technologies have been used to develop longer-acting therapeutic proteins. One approach is to introduce sequences containing additional glycosylation sites. Using this technique, a new chimeric gene has been developed containing the coding sequences of the FSH beta-subunit and the C-terminal peptide of the hCG beta-subunit, which bears four O-linked oligosaccharide binding sites. Co-expression of the alpha-subunit and the chimeric FSH beta-subunit produces a new recombinant molecule, named corifollitropin alfa, with a prolonged elimination half-life and enhanced in vivo bioactivity compared with wild-type FSH. METHODS: Medline searches by subject and additional searching by hand. RESULTS: Initial studies in pituitary suppressed female volunteers confirmed the extended half-life of the compound. Phase II studies have shown that corifollitropin alfa is able to induce and sustain multi-follicular growth for an entire week in women undergoing ovarian stimulation using GnRH antagonist co-treatment for IVF. Corifollitropin alfa regimens have been developed with dosages of 100 and 150 microg, for patients with body weight 60 kg, respectively. CONCLUSIONS: Corifollitropin alfa is the first long-acting hybrid molecule with sustained follicle-stimulating activity developed for the induction of multi-follicular growth along with GnRH antagonist co-treatment for IVF. This new treatment option may be simpler and more convenient for patients compared with conventional long protocols of daily FSH injections in combination with GnRH agonist co-treatment. The safety and efficacy of such regimens is currently being evaluated in large comparative phase III clinical trials. The development of corifollitropin alfa is the first step towards a new generation of recombinant gonadotrophins.

Breed differences in clearance of porcine FSH in hypophysectomized rats.

Extracts of anterior pituitary (AP) glands were infused i.v. into hypophysectomized male rats followed by sequential sampling of blood for 120 min. Determination of follicle-stimulating hormone (FSH) concentrations established that FSH from Chinese Meishan males decreased in the circulation of rats more slowly than FSH in extracts of AP from crossbred occidental pigs (P<0.003). Additionally, FSH from AP extracts of castrated males disappeared somewhat more slowly (P<0.06) than FSH from extracts of boars. Evaluation of FSH by bioassay and radioimmunoassay yielded similar concentrations in AP from Meishan and crossbred boars. Serum testosterone concentrations increased with time through 90 min after infusion of AP, but the rate of increase of testosterone was not related to amount of luteinizing hormone (LH) that was administered indicating LH receptor saturation. Unexpectedly, the rate of increase in testosterone was more rapid with AP extracts from boars than with extracts from castrated males. Observations from the current study imply structural alterations of FSH in the AP of Meishan males relative to crossbred males allowing sustained concentrations in the circulation, and this FSH possesses similar activation of the FSH receptor. The amount of LH in the AP extracts saturated the LH receptors of the hypophysectomized male rats, but some factor in extracts of boars differed from those of castrated males.

Effects of breed on kinetics of ovine FSH and ovarian response in superovulated sheep.

Embryo production is a useful tool for ex situ conservation of endangered species and breeds, despite a high variability in the ovarian response to superovulatory treatments. The current study evaluated the incidence and mechanisms of genetic factors in such variability, by determining the pharmacokinetics and pharmacodynamics of a standard treatment with ovine FSH (oFSH) in two endangered Spanish sheep breeds (Rubia del Molar, R, and Negra de Colmenar, N) in comparison to Manchega ewes (M, control group). In the first experiment, pharmacokinetics of an i.m. single dose of 1.32 mg of oFSH was evaluated in seven animals of each breed. Plasma FSH concentrations reached their maximum at 4h post-administration in all the ewes, but several of the kinetic parameters (plasma FSH concentration at 4h post-administration, maximum plasma FSH concentration, C(max), and both the area under the plasma concentration-time curve extrapolated to the infinite, AUC(inf), and to the last moment of sampling, AUC(last)) were higher in the N group. In the second trial, 10 animals of each breed were superovulated using eight decreasing doses of oFSH (3 x 1.32 mg, 2 x 1.10 mg, and 3 x 0.88 mg). The R group, when compared to N and M, showed both a higher number of corpora lutea (13.7+/-0.6 versus 10.0+/-0.4 in N and 9.8+/-0.6 in M, P<0.05 for both) and embryos (7.9+/-0.8 versus 4.3+/-0.4 in N, P<0.05, and 6.7+/-0.5 in M, n.s.). Evaluation of pharmacokinetic and dynamic parameters showed that, although there was a trend for a higher hormone availability in R sheep, mean FSH plasma concentrations were similar between breeds (0.54+/-0.08 ng/ml for R, 0.45+/-0.05 ng/ml for N and 0.35+/-0.05 ng/ml for M). However, differences were found in the number of preovulatory follicles growing in response to the FSH treatment between R (24.4+/-2.2), M (18.9+/-1.5, n.s.) and N sheep (14.1+/-1.4; P<0.01). Thus, differences in embryo yields between breeds would be related to differences in the pattern of follicular growth in response to FSH treatment.

Molecular pharmacology of gonadotropins.

Gonadotropins have been studied in biological systems for decades and many of their properties are well defined. These include pharmacological properties such as affinity, stability, and pharmacokinetics also used to characterize drugs. Technologies applied to research on gonadotropins have led to the creation of hormone analogs with alterations to one or more of these proper-ties. Some of these analogs have potential therapeutic applications. A challenge to realizing this potential is the accurate prediction of how these compounds will perform in humans. This could be facilitated by advances in biological models and the understanding of specific effects of the hormones on their receptors.

Urofollitropin and ovulation induction.

Anovulation is a common cause of female infertility. Treatment for women with anovulation is aimed at induction of ovulation. Ovulation induction with follicle-stimulating hormone (FSH) is indicated in women with WHO type II anovulation in whom treatment with clomifene citrate (clomifene) has failed. The majority of these women have polycystic ovary syndrome. The major disadvantages of ovulation induction with FSH are the risk of ovarian hyperstimulation syndrome and the risk of higher order multiple pregnancies. To reduce the rate of complications due to multiple follicular development, FSH should be administered using a chronic low-dose protocol with small dose increments. In women with WHO type I anovulation, an exogenous supply of luteinizing hormone (LH) is required to achieve an adequate follicular response to FSH treatment. Thus, ovulation induction with FSH is not the treatment of choice in these women. FSH is a hormone that stimulates follicle growth and oocyte maturation. Endogenous FSH is produced by the pituitary gland and exists as a family of isohormones exhibiting distinct oligosaccharide structures. FSH for exogenous administration is derived from urine or is produced as recombinant FSH. The commercially available FSH products all contain different mixtures of FSH isoforms. To determine the effectiveness of urofollitropin (urinary-derived FSH), a comparison with the other available gonadotropins was made (i.e. recombinant FSH and human menopausal gonadotropin). Urofollitropin and recombinant FSH appear to be equally effective and well tolerated for ovulation induction. Human menopausal gonadotropin is comparably effective to urofollitropin in terms of pregnancy outcomes. It remains unclear whether human menopausal gonadotropins have a higher risk of overstimulation and ovarian hyperstimulation syndrome compared to urofollitropin in women with polycystic ovary syndrome. In practice, recombinant products are more convenient to use but are also more expensive. Therefore, if availability is not an issue but costs are, there is still a place for the use of urofollitropins for ovulation induction.

Bioequivalence of liquid and freeze-dried recombinant human follicle-stimulating hormone.

OBJECTIVE: The bioequivalence and tolerability of freeze-dried and liquid formulations of recombinant human follicle-stimulating hormone (r-hFSH) filled-by-mass were assessed in a crossover, open-label, randomised, single-centre, phase I bioequivalence study. METHODS: Following pituitary down-regulation with the gonadotrophin-releasing hormone agonist goserelin, healthy adult volunteers (18years-45years of age) received single subcutaneous injections of r-hFSH , 300 IU, from freeze-dried and liquid formulations in random order, separated by a 7-day washout period. Blood was obtained over 144 h for pharmacokinetic analysis. MAIN OUTCOME MEASURES: These were peak serum FSH concentrations (Cmax,), time to peak concentration (Tmax) and area under the concentration-time curve from zero to the last measurable concentration (AUCJ), local and systemic tolerability. RESULTS: Of 44 volunteers who underwent down-regulation, 39 (18 men, 21 women) completed the study. Cmax and AUClast were similar with the freeze-dried (mean 9.51 IU/L and 844 IU.h/L, respectively) and liquid (mean 8.99 IU/L and 841 IUh/L, respectively) formulations, whereas T was significantly higher with the liquid formulation (median 12h vs 15h, p = 0.0183). The 90% confidence intervals for the ratio of the treatment means for Cnw and AUC,=, were within the pre-defined bioequivalence range of 0.8-1.25. CONCLUSION: Both formulations were well tolerated with regard to both systemic and local adverse events. The freeze-dried and liquid formulations of r-hFSH are bioequivalent and show no significant differences in tolerability. Thus, the liquid formulation is expected to provide comparable efficacy and tolerability to the freeze-dried formulation in clinical use.