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

The influence of the pharmaceutical industry on the development of gonadotrophins and ovarian stimulation protocols in assisted reproductive technologies

Introduction

This review examines the evolution of gonadotrophins in ovarian stimulation (OS) protocols for assisted reproductive techniques (ART). Since the advent of in vitro fertilisation (IVF) in the late 1970s, the pharmaceutical industry has played a pivotal role in advancing gonadotrophin production, improving drug purity and optimising delivery methods. Despite significant progress, questions remain about the robustness of the evidence supporting the use of different gonadotrophins and the impact of industry-driven research on clinical practice. The review critically examines the evolution, evidence and future directions of gonadotrophin use in ART.

Methods

A comprehensive literature search was carried out in multiple databases to select articles/reviews on historical developments, manufacturing and analytical techniques, regulatory frameworks and clinical trials undertaken to assess gonadotrophin production, formulation processes and their integration into clinical practice. The analysis included mainly evidence from pharmaceutical sponsored randomised controlled trials (RCTs) as well as single arm, registration or post approval studies. Studies on new molecular entities were reviewed. Systematic reviews and meta-analyses, national registries were consulted. Laboratory developments, regulatory challenges, economic constraints, were considered.

Results

Over the past four decades, ART has seen remarkable improvements, including increased live birth rates in women of advanced ovarian age, reduced multiple births, and the advent of patient-friendly pen devices. Innovations such as recombinant FSH (rFSH) and biosimilars have expanded treatment options. However, the high cost of drug development as well as the complexity of the ART process have contributed to underpowered trials and reliance on meta-analyses, which often fail to account for confounding factors.

Discussion

While gonadotrophins have been shown to be effective for OS, unresolved issues, such as the role of supplementing LH activity in OS protocols, highlight the need for more robust trials. Collaboration between stakeholders is essential to standardise trial designs, define key outcomes and minimise bias. Emerging technologies, including AI and genetic testing, offer opportunities to refine embryo assessment and implantation outcomes, thus improving trial design. A renewed focus on rigorous, transparent trials and interdisciplinary collaboration is essential to advance patient care and address unmet challenges in ART treatment. Beyond gonadotrophins, alternative therapeutic avenues to improve oocyte competence and implantation success warrant exploration.

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 T_max occurred at 240-312 h, and the half-life (t_½) 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).

First pre-filled pen device with highly purified human menopausal gonadotropin (HP-hMG, Menopur) in liquid is shown to be bioequivalent to powder for reconstitution

OBJECTIVE

To determine whether serum human follicle-stimulating hormone (FSH) levels after single subcutaneous dosing of highly purified human menopausal gonadotropins (HP-hMG) in a liquid formulation and a powder formulation are bioequivalent.

MATERIALS AND METHODS

This was a randomized, two-way, crossover, single-dose, bioequivalence trial comparing Menopur liquid injected by pre-filled pen, with Menopur powder injected by conventional syringe and needle. The primary endpoints were AUC_t and C_max of baseline-adjusted FSH. Pituitary-suppressed, healthy women were administered single subcutaneous injections of 450 IU Menopur liquid (600 IU/0.96 mL) and 450 IU Menopur powder (by 2 subcutaneous injections of 225 IU in 1 mL) in a randomized order. The pharmacokinetic parameters of FSH and human chorionic gonadotropin (hCG) were assessed by non-compartmental methods with adjustment for endogenous pre-dose levels.

RESULTS

In total, 76 women were randomized, and 56 completed the trial. The mean FSH and hCG serum concentration-time profiles were comparable between the two HP-hMG formulations. The geometric mean ratios and 90% confidence intervals of FSH for HP-hMG liquid versus HP-hMG powder were 1.12 (1.0562 - 1.1889) for AUC_t and 1.17 (1.0946 - 1.2490) for C_max, showing that the two formulations were bioequivalent. The incidence and severity of adverse events were similar between the two preparations, and both preparations were well tolerated.

CONCLUSION

The 90% CIs for the geometric mean ratios of serum FSH AUC_t and C_max were both within 0.8000 - 1.2500, thus the two formulations are bioequivalent.

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 (AUC_Inhb ) at the end of stimulation cycles that varied in length in each woman. In the second stage, the estimated AUC_Inhb 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). AUC_Inhb could be predicted with women's age and weight. Log-transformed AUC_Inhb was a significant covariate when tested against oocyte retrieval (P < .001). Simulations concluded a target AUC_Inhb 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.

A gold mine for drug discovery: Strategies to develop cyclic peptides into therapies

As a versatile therapeutic modality, peptides attract much attention because of their great binding affinity, low toxicity, and the capability of targeting traditionally "undruggable" protein surfaces. However, the deficiency of cell permeability and metabolic stability always limits the success of in vitro bioactive peptides as drug candidates. Peptide macrocyclization is one of the most established strategies to overcome these limitations. Over the past decades, more than 40 cyclic peptide drugs have been clinically approved, the vast majority of which are derived from natural products. The de novo discovered cyclic peptides on the basis of rational design and in vitro evolution, have also enabled the binding with targets for which nature provides no solutions. The current review summarizes different classes of cyclic peptides with diverse biological activities, and presents an overview of various approaches to develop cyclic peptide-based drug candidates, drawing upon series of examples to illustrate each strategy.

Heterogeneous hCG and hMG commercial preparations result in different intracellular signalling but induce a similar long-term progesterone response in vitro

STUDY QUESTION

Are four urinary hCG/menotropin (hMG) and one recombinant preparation characterized by different molecular features and do they mediate specific intracellular signaling and steroidogenesis?

SUMMARY ANSWER

hCG and hMG preparations have heterogeneous compositions and mediate preparation-specific cell signaling and early steroidogenesis, although similar progesterone plateau levels are achieved in 24 h-treated human primary granulosa cells in vitro.

WHAT IS KNOWN ALREADY

hCG is the pregnancy hormone marketed as a drug for ARTs to induce final oocyte maturation and ovulation, and to support FSH action. Several hCG formulations are commercially available, differing in source, purification methods and biochemical composition.

STUDY DESIGN, SIZE, DURATION

Commercial hCG preparations for ART or research purposes were compared in vitro.

PARTICIPANTS/MATERIALS, SETTING, METHODS

The different preparations were quantified by immunoassay with calibration against the hCG standard (Fifth IS; NIBSC 07/364). Immunoreactivity patterns, isoelectric points and oligosaccharide contents of hCGs were evaluated using reducing and non-reducing Western blotting, capillary isoelectric-focusing immunoassay and lectin-ELISA, respectively. Functional studies were performed in order to evaluate intracellular and total cAMP, progesterone production and β-arrestin 2 recruitment by ELISA and BRET, in both human primary granulosa lutein cells (hGLC) and luteinizing hormone (LH)/hCG receptor (LHCGR)-transfected HEK293 cells, stimulated by increasing hormone concentrations. Statistical analysis was performed using two-way ANOVA and Bonferroni post-test or Mann-Whitney's U-test as appropriate.

MAIN RESULTS AND THE ROLE OF CHANCE

Heterogeneous profiles were found among preparations, revealing specific molecular weight patterns (20-75 KDa range), isoelectric points (4.0-9.0 pI range) and lectin binding (P < 0.05; n = 7-10). These drug-specific compositions were linked to different potencies on cAMP production (EC50 1.0-400.0 ng/ml range) and β-arrestin 2 recruitment (EC50 0.03-2.0 μg/ml) in hGLC and transfected HEK293 cells (P < 0.05; n = 3-5). In hGLC, these differences were reflected by preparation-specific 8-h progesterone production although similar plateau levels of progesterone were acheived by 24-h treatment (P ≥ 0.05; n = 3).

LARGE SCALE DATA

N/A.

LIMITATIONS, REASONS FOR CAUTION

The biological activity of commercial hCG/hMG preparations is provided in International Units (IU) by in-vivo bioassay and calibration against an International Standard, although it is an unsuitable unit of measure for in-vitro studies. The re-calibration against recombinant hCG,quantified in grams, is based on the assumption that all of the isoforms and glycosylation variants have similar immunoreactivity.

WIDER IMPLICATIONS OF THE FINDINGS

hCG/hMG preparation-specific cell responses in vitro may be proposed to ART patients affected by peculiar ovarian response, such as that caused by polycystic ovary syndrome. Otherwise, all the preparations available for ART may provide a similar clinical outcome in healthy women.

STUDY FUNDING AND COMPETING INTEREST(S)

This study was supported by a grant of the Italian Ministry of Education, University and Research (PRIN 2015XCR88M). The authors have no conflict of interest.