The Gonadotropin Foundation: Recombinant FSH and Biosimilar Competition
Recombinant FSH preparations remain the dominant pharmacological backbone of controlled ovarian stimulation (COS), with follitropin alfa and follitropin delta distinguished primarily by their cell-line origin and consequent glycosylation profiles. Follitropin alfa is expressed in Chinese Hamster Ovary (CHO) cells, while follitropin delta is expressed in the human PER.C6 cell line — a difference that governs pharmacokinetic behavior through differential clearance by the hepatic asialoglycoprotein receptor (ASGPR). Follitropin delta’s more acidic isoform composition results in slower ASGPR-dependent clearance relative to follitropin alfa, as documented by Bio-Technology General Israel and Ferring in 2017.
Patent families from Merck Serono S.A., Applied Research Systems ARS Holding N.V., and Laboratoires Serono S.A. claim FSH dosing regimens of 300–600 IU administered every third day during the first six days of stimulation as a departure from the conventional daily dosing paradigm, targeting improved follicular recruitment. Comparative clinical evidence of highly purified urinary FSH (uFSH) versus recombinant FSH in women over 37 years is provided by Yantai Yuhuangding Hospital (2015), noting the longer half-life and higher biological activity of acidic FSH isoforms in uFSH preparations. Biosimilar FSH preparations have also entered the evidence base, with Assiut University (2018) publishing comparisons against highly purified urinary FSH for simple ovulation induction in women with PCOS — signalling an emerging generics tier within the gonadotropin category.
Follitropin delta, expressed in the human PER.C6 cell line, has slower clearance than follitropin alfa due to its more acidic isoform composition and hepatic asialoglycoprotein receptor (ASGPR)-dependent elimination, as documented by Bio-Technology General Israel and Ferring in 2017.
Ferring B.V.’s 2021 EP patent — the only active-status patent in the gonadotropin category retrieved in this dataset — introduces pharmacogenomics-guided dosing of follitropin delta based on the FSHR Ser680/Ser680 genotype, claiming patient stratification by FSHR Asn680Ser polymorphism and a reduced-dose range of 9–24 pg for Ser/Ser homozygotes. This positions pharmacogenomics-guided FSH dosing as an active and commercially protected IP area, extending beyond the blunt instrument of body-weight-based starting doses.
High-dose FSH has been identified as a mechanism for poor outcomes in diminished ovarian reserve (DOR): down-regulation of FSH-dependent enzymes CYP19A1 and HSD3B, along with cytokines required for implantation, is described by Cooper Medical School of Rowan University (2022) as a rationale for lower FSH dose strategies that favour receptor up-regulation rather than saturation. According to WHO, infertility affects approximately 17.5% of adults globally, underlining the scale of unmet clinical need that these dosing refinements seek to address.
Beyond Injectables: Oral FSH Receptor Agonists and Peptide Mimetics
Oral, non-peptidic FSH receptor allosteric agonists represent the most structurally novel modality in this dataset, with the potential to replace subcutaneous gonadotropin injections for ovulation induction or COS-IVF. Applied Research Systems ARS Holding N.V. filed the foundational patent covering cyclic and acyclic alpha- and beta-aminocarboxamides, tetrahydroisoquinolinecarboxamides, piperidinecarboxamides, pyrrolidinecarboxamides, and 2-amino-3-carboxamidopyridine derivatives as FSH agonist scaffolds, though this filing is now inactive — potentially opening the scaffold space to new entrants.
An allosteric agonist binds to a site on the FSH receptor distinct from the natural FSH binding site, inducing receptor activation without requiring the full FSH protein. This enables small, orally bioavailable molecules to mimic the action of the large glycoprotein hormone, potentially eliminating the need for injectable gonadotropin preparations.
Baylor College of Medicine (2021) provided preclinical proof of concept for compounds TOP5668 and TOP5300 as FSHR allosteric agonists, describing pharmacokinetics, drug metabolism, and safety profiles deemed suitable for ovulation induction or COS-IVF, with efficacy comparable to recombinant hFSH in CHO cell in vitro models. These compounds remain at preclinical stage — no clinical trial data were retrieved in this dataset. A parallel approach using synthetic FSH-beta peptide fragments is reported by Sichuan Agricultural University (2022): peptides hFSH-β-(37–49) and hFSH-β-(34–49) administered to prepubertal mice at 200 µg/g body weight accelerated puberty and promoted gonadal steroidogenesis, representing early preclinical exploration of receptor-binding peptide fragments as fertility agents.
“Oral FSH receptor allosteric agonists TOP5668 and TOP5300 achieved efficacy comparable to recombinant hFSH in CHO cell in vitro models, with pharmacokinetic and safety profiles characterised as suitable for IND-enabling studies — yet no clinical trial data have been retrieved for either compound.”
The structural diversity of scaffolds claimed across the FSH mimetics patent space — from aminocarboxamides to tetrahydroisoquinolinecarboxamides — suggests that multiple chemotypes are being explored for FSHR allosteric binding, consistent with the early-stage, exploratory nature of this modality. As noted by NIH, developing orally active gonadotropin mimetics has been a long-standing goal in reproductive medicine given the burden of daily injectable regimens on patients undergoing IVF.
Explore the full oral FSH receptor agonist patent landscape in PatSnap Eureka — including scaffold analysis and assignee timelines.
Explore Patent Data in PatSnap Eureka →AMH as Both Biomarker and Therapeutic Target in Ovarian Reserve Assessment
Anti-Müllerian hormone (AMH) occupies a unique dual position in the female infertility landscape: it is simultaneously the most accurate quantitative biomarker of ovarian reserve and an emerging therapeutic agent in its own right. AMH is a member of the TGF-beta superfamily secreted by granulosa cells of preantral and small antral follicles, and retrieved results from multiple clinical sites — including Singapore General Hospital and Fayoum University Egypt — confirm that basal AMH and antral follicle count (AFC) together outperform basal FSH, LH, and estradiol as predictors of both poor and hyper-ovarian response in controlled stimulation cycles.
Basal AMH and antral follicle count (AFC) are the strongest predictors of poor and hyper-ovarian response in controlled ovarian stimulation cycles, outperforming basal FSH, LH, and estradiol, according to clinical data from Singapore General Hospital and Fayoum University Egypt.
The PIVET Medical Centre Perth documented a 10-year observational study validating AMH- and AFC-guided rFSH dosing algorithms across two pen-delivery devices, with the clinical objective of collecting 15 or fewer oocytes and minimising OHSS risk — representing clinically implemented precision dosing rather than investigational protocol design. The Ferring B.V. 2021 EP patent extends this further into pharmacogenomics, combining AMH-guided dosing with FSHR Ser680/Ser680 genotyping to refine follitropin delta starting doses to a range of 9–24 pg in Ser/Ser homozygotes.
On the therapeutic axis, Inserm U1185, Université Paris-Saclay, describes AMH’s dual role as an inhibitor of primordial follicle activation and a potential protective agent against chemotherapy-induced ovarian damage. Recombinant AMH protein is positioned as an emerging oncofertility intervention to protect the primordial follicle pool from chemotherapy-induced depletion — a mechanistically distinct use case from its diagnostic application. Huazhong Agricultural University (2021) demonstrated additive inhibitory effects of AMH and inhibin on FSH-induced estradiol and progesterone production in granulosa cells in vitro, with AMH and inhibin synergistically downregulating CYP19A1 and HSD3B — enzymes critical to follicular steroidogenesis.
A further signal from Nanjing Medical University (2022) identifies a significant positive correlation between serum insulin-like peptide 5 (INSL5) and AMH in women with PCOS, implicating the INSL5-AMH axis as a potential novel biomarker or therapeutic target in PCOS-related infertility — extending the AMH signalling network beyond its established granulosa cell biology. According to ESHRE, AMH measurement has become a standard component of ovarian reserve assessment in ART practice across Europe.
AMH, BMP-15, and TGF-β1 concentrations in follicular fluid differ between natural and stimulated IVF cycles, as demonstrated by University Medical Centre Ljubljana (2019), potentially explaining the lower pregnancy rates observed in natural IVF cycles relative to stimulated cycles.
Protocol Innovation: GnRH Analogs, PPOS, and Kisspeptin Ovulation Triggers
GnRH agonist and antagonist protocols form the scaffolding within which FSH and LH supplementation operates, and twelve or more retrieved papers address protocol comparisons across DOR, PCOS, and normal responder phenotypes. Zentaris IVF GmbH systematically codified the full COS workflow in patent families covering GnRH antagonist-mediated suppression of premature LH surge, OCP/progestogen pre-treatment for cycle programming, exogenous gonadotropin stimulation, ovulation triggering with hCG or GnRH agonist, and ART procedures — though these filings are now inactive.
The GnRH agonist “dual trigger” — combining triptorelin with recombinant hCG — is evaluated clinically in fertility preservation cycles at Seoul National University Bundang Hospital (2022), with subgroup analysis in DOR patients defined by AMH below 1.1 ng/ml. This approach targets optimisation of mature oocyte yield while managing OHSS risk, representing a protocol-level refinement rather than a new molecular entity.
Progestin-primed ovarian stimulation (PPOS) has emerged as a patient-friendly alternative to GnRH analog-based suppression. In PPOS protocols, medroxyprogesterone acetate (MPA) or dydrogesterone replaces GnRH analogs to suppress premature LH surge, while corifollitropin alfa — a long-acting FSH — is co-administered as a single subcutaneous injection to reduce the total number of injections and clinic visits. Clinical data from National Yang-Ming University and Taipei Veterans General Hospital (both 2020) report comparable reproductive outcomes to antagonist protocols in normal and high responders, with all-freeze embryo transfer used to circumvent the progesterone effect on endometrial receptivity. This protocol is in clinical use in Asia and Europe.
Progestin-primed ovarian stimulation (PPOS) using medroxyprogesterone acetate combined with corifollitropin alfa reported comparable reproductive outcomes to GnRH antagonist protocols in normal and high responders, according to clinical data from National Yang-Ming University and Taipei Veterans General Hospital (2020), with all-freeze embryo transfer used to bypass the progesterone effect on endometrial receptivity.
Kisspeptins are identified across retrieved literature as central neuroendocrine regulators capable of eliciting an endogenous LH surge for final oocyte maturation, positioning them as next-generation ovulation trigger candidates. Instituto Bernabeu (2014) frames GnRH agonist triggering as a paradigm shift over hCG in reducing OHSS risk, and positions kisspeptins as the subsequent step in this evolution. Sumitomo Pharma Switzerland GmbH filed two pending IL-jurisdiction patents in 2024 covering a specific kisspeptin-analog peptide for promoting oocyte maturation in IVF, reducing OHSS, inhibiting premature ovulation, and improving pregnancy rates, with specific claims for PCOS patients and women with AMH greater than 15 pmol/L. Based on filing content and specificity, the development stage is estimated as late preclinical to Phase I/II — and these represent the most recent active filings in the entire dataset.
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Analyse Kisspeptin Patents in PatSnap Eureka →Regenerative and Immunomodulatory Approaches for Ovarian Reserve Restoration
Intraovarian platelet-rich plasma (PRP) injection, in vitro follicular activation (IVA), and stem cell therapies for DOR and POI represent the most experimental cluster in this dataset, with no approved indications identified across the retrieved records. A registered prospective clinical trial conducted at the University of Westminster (2020) in 182 patients reported AMH improvement in 28% of treated patients following intraovarian injection of activated autologous PRP, with a median AMH increase of 167% in responders — a striking effect size that warrants controlled replication.
A registered prospective clinical trial of intraovarian injection of activated autologous platelet-rich plasma (PRP) in 182 patients with poor prognosis for IVF reported AMH improvement in 28% of treated patients, with a median AMH increase of 167% among responders, according to University of Westminster (2020).
IDIBAPS Barcelona (2021) reviews in vitro follicular activation (IVA) as an approach to activate dormant primordial follicles via PI3K/Akt/mTOR signalling pathways in women with DOR and POI. A prospective study from National Cheng Kung University Hospital Taiwan (N=46) demonstrates the clinical feasibility of intraovarian injection of 300 IU recombinant human FSH for luteal-phase ovarian stimulation in DOR patients, representing a novel route of administration for an established molecule rather than a new compound.
On the immunomodulatory axis, Ramot at Tel-Aviv University Ltd. holds patents claiming IL-1 inhibitors for retaining ovarian follicle reserve, improving COS responsiveness, and enhancing oocyte quality in IVF — an approach mechanistically distinct from gonadotropin-based stimulation. Merck Serono S.A. and Applied Research Systems ARS Holding N.V. hold a separate patent family covering IL-17 as a cytokine adjuvant for in vitro maturation (IVM) of mammalian oocytes, intended to improve IVF protocols. Both IL-1 and IL-17 pathway interventions are at preclinical to early translational stage in this dataset.
DHEA supplementation as a pre-treatment for DOR has the deepest clinical evidence base among adjuvant strategies, with multiple randomised controlled trials and meta-analyses present in the dataset. A multicenter RCT protocol registered in China (Shandong University, 2019) signals mid-stage clinical investigation. A further randomised trial from Anhui Medical University (2016) evaluated DHEA combined with estradiol valerate/cyproterone acetate (climen) in DOR patients with low basal FSH below 10 IU/L, reporting superior results over DHEA monotherapy. Gene therapy using adeno-associated virus-mediated delivery crossing the blood-follicle barrier is characterised by Indian Institute of Technology Kanpur (2022) as an emerging but pre-clinical direction for oogenesis restoration. As reported by NCBI/PubMed, research into ovarian rejuvenation strategies has accelerated substantially since 2018, reflecting growing demand for fertility preservation options in older and oncology patient populations.
Assignee Landscape, IP Status, and Competitive White Space
Innovation activity in this dataset is distributed across large pharmaceutical companies, specialised biotechs, academic medical centres, and reproductive medicine clinics, with a clear bifurcation between patent-driven and literature-driven modalities. Patent-driven activity dominates in FSH dosing regimens, FSH mimetics, COS protocol kits, and kisspeptin analogs; literature-driven activity dominates in biomarker individualisation, adjuvant therapies (DHEA, PRP, inositols), and DOR/POI treatment strategies.
The most patent-prolific assignee cluster — Merck Serono S.A., Applied Research Systems ARS Holding N.V., and Laboratoires Serono S.A. — holds multiple families covering FSH dosing regimens, FSH mimetics, and IL-17-mediated oocyte maturation, but all are currently inactive, suggesting these core gonadotropin dosing and mimetic patents have expired or lapsed. This creates potential white space for new entrants across FSH dosing regimens and small-molecule FSHR agonist scaffolds. Ferring B.V.’s active 2021 EP patent on pharmacogenomics-guided follitropin delta dosing represents the sole active commercial IP protection in the gonadotropin category retrieved. Sumitomo Pharma Switzerland GmbH’s two 2024 pending kisspeptin-analog patents are the most recent active filings in the dataset, signalling current commercial development interest. According to WIPO, reproductive medicine has been among the fastest-growing therapeutic areas for patent filings over the past decade, driven by increasing demand for ART globally.
Academic groups driving the literature component include Baylor College of Medicine (oral FSHR agonists), Inserm Paris-Saclay (AMH oncofertility), Huazhong Agricultural University (inhibin-AMH synergy), Sichuan Agricultural University (FSH-beta peptides), and IDIBAPS Barcelona (IVA and stem cell). The academic-industrial IP axis in non-gonadotropin modalities is represented primarily by Ramot at Tel-Aviv University and Merck Serono, though both relationships have yielded inactive patents in this dataset. Explore the full PatSnap pharmaceutical intelligence platform for deep-dive assignee mapping and citation network analysis across the reproductive medicine patent landscape.