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FDA Approved Sexual & Reproductive Health

Follitropin beta

also known as: Follistim, Follistim AQ, Puregon, rFSH beta

Organon/Merck's Follistim AQ (Puregon internationally) — a recombinant human FSH produced independently of follitropin alfa but clinically equivalent; FDA-approved 1997 for ovulation induction and IVF controlled ovarian stimulation.

A recombinant human FSH produced in CHO cells, developed and marketed by Organon (now Merck/MSD). Amino acid sequence identical to endogenous FSH and to follitropin alfa; the two products differ only in expression-cell-line-specific glycosylation signatures, which are not clinically distinguishable in head-to-head trials. FDA-approved in 1997 under the brand name Follistim (later Follistim AQ, aqueous formulation); marketed internationally as Puregon.

Mechanism of action

FSHR agonism on granulosa cells — identical in mechanism and clinical effect to follitropin alfa. Drives follicular recruitment and maturation during the controlled-ovarian-stimulation or ovulation-induction cycle.

Primary uses

  • Anovulatory infertility (non-primary-ovarian-failure)
  • Controlled ovarian stimulation in IVF/ICSI

Typical dosing

50–450 IU/day daily (subcutaneous)

Ovulation induction: 75 IU/day SC starting dose, titrated. IVF: 150–300 IU/day SC. Delivered via Follistim Pen cartridges of 300, 600, or 900 IU.

Regulatory status

FDA-approved as Follistim (follitropin beta, Organon/Merck, first approved September 1997); reformulated and relaunched as Follistim AQ (aqueous) and Follistim AQ Cartridge for use with the Follistim Pen delivery device. Indications: induction of ovulation in ovulatory-dysfunction infertility; development of multiple follicles in women undergoing assisted reproductive technologies.

References

  1. [fda-pi] Follistim AQ (follitropin beta injection) Prescribing Information. Organon USA / Merck.
  2. [pubmed] Al-Inany HG, et al. "Recombinant versus urinary human chorionic gonadotrophin for ovulation induction in assisted conception." Cochrane Database Syst Rev, 2005;(2):CD003719 (systematic-review context for rFSH equivalence).

Related peptides

Follitropin alfa

EMD Serono's Gonal-f — the first recombinant human FSH approved by the FDA (1997). Used for ovulation induction, IVF controlled ovarian stimulation, and male hypogonadotropic hypogonadism fertility induction.

Follitropin delta

Ferring's Rekovelle — a recombinant human FSH produced in a human cell line (PER.C6), dosed via a personalized algorithm based on serum AMH and body weight. Approved in the EU, UK, Canada, Australia, Japan, and China, but received an FDA Complete Response Letter in February 2026 over manufacturing issues; not currently approved in the United States.

Urofollitropin

Ferring's Bravelle (and earlier Fertinex) — highly purified urinary-derived FSH used for ovulation induction and IVF controlled ovarian stimulation. FDA-approved 2002; branded Bravelle was withdrawn from the US market in 2015 due to manufacturing/potency concerns but the molecule class remains available via urinary-derived menotropin combination products.

Menotropin

Ferring's Menopur (and earlier Repronex, Humegon) — a urinary-derived FSH/LH combination used for ovulation induction and IVF controlled ovarian stimulation, particularly when LH supplementation is clinically desired.

HCG

An FDA-approved fertility and hypogonadism medication commonly discussed in peptide and TRT communities for post-cycle recovery and testicular preservation during testosterone therapy.

Ganirelix

Organon/Merck's Ganirelix Acetate (formerly Antagon; Orgalutran internationally) — a GnRH antagonist functionally equivalent to cetrorelix for IVF LH-surge prevention, dosed as a daily fixed 250 mcg SC injection.

Guides & tools

Disclaimer

This entry is for educational purposes only and does not constitute medical advice. Dosing information reflects published regulatory or research data and is not a recommendation. Many compounds described here are not approved for human use in the United States. Consult a licensed medical professional before considering any peptide therapy.