rFSH

rFSH is a Follicle Stimulating Hormone (FSH) preparation of recombinant DNA origin, which consists of two non-covalently linked, nonidentical glycoproteins designated as the α- and β subunits. The α- and β-subunits have 92 and 111 amino acids respectively, and their primary and tertiary structure are indistinguishable from those of human Follicle Stimulating Hormone. Recombinant FSH production occurs in genetically modified Chinese Hamster Ovary (CHO) cells cultured in bioreactors. Purification by immunochromatography using an antibody specifically binding FSH results in a highly purified preparation with a consistent FSH isoform profile and a high specific activity. The biological activity of rFSH is determined by measuring the increase in ovary weight in female rats. The in vivo biological activity of rFSH has been calibrated against the first International Standard for Recombinant Human Follicle Stimulating Hormone established in 1995 by the Expert Committee on Biological Standards of the World Health Organization. rFSH contains no Luteinizing Hormone (LH) activity.

Recombinant FSH sometimes excites the ovaries too much. This may cause pelvic pain or breathing problems. It may also make you urinate less. In rare cases, patients with this problem have had serious lung problems, including fluid in the lungs, troublebreathing, and worsening of asthma blood clots, Severe Pelvic pain, Chest pain, or Abdominal pain, Nausea, Vomiting, Sudden weight gain, Bloating, Trouble, Breathing. Recombinant FSH may cause twins or multiple births.

Pregnancy category X. Recombinant FSH must not be used during pregnancy and lactation.

• The presence of uncontrolled non gonodal endocrinopathies (e.g. thyroid, adrenal or pituitary disorders) should be excluded.
• In pregnancies occurring after induction of ovulation with gonadotrophin preparations, there is an increased risk of multiple gestations (Multiple birth).
• There has been no reports of hypersensitivity to Recombinant FSH, but there remains the possibility of anaphylactic responses.
• The first injection of Recombinant FSH should be performed under direct medical supervision.
• Since infertile women undergoing assisted reproduction and particularly IVF, often have tubal abnormalities the incidence of ectopic pregnancies might be increased. Early ultrasound confirmation that a pregnancy is intrauterine is therefore important.
• Rates of pregnancy loss in women undergoing assisted reproduction techniques are higher than in the normal population.
• Unwanted ovarian hyperstimulation in the treatment of female patients, ultrasonographic assessment of follicular development, and determination of oestradiol levels should be performed prior to treatment and at regular intervals during treatment. Apart from the development of a high number of follicles, oestradiol levels may rise very rapidly, e.g. more than a daily doubling for two or three consecutive days, and possibly reaching excessively high values. The diagnosis of ovarian hyperstimulation may be confirmed by ultrasound examination. If this unwanted ovarian hyperstimulation occurs (i.e. not as part of controlled ovarian hyperstimulation in medically assisted reproduction programs), the administration of Recombinant FSH should be discontinued. In that case pregnancy should be avoided and HCG must be withheld, because it may induce in addition to multiple ovulation, the Ovarian Hyperstimulation Syndrome (OHSS).
• In men, semen analysis is recommended 4 to 6 months after the beginning of treatment in assessing the response.

Drugs for Infertility, Trophic Hormones & Related Synthetic Drugs

No data on acute toxicity of Recombinant FSH in humans is available, but the acute toxicity of Recombinant FSH and of urinary gonadotrophin preparations in animal studies have been shown to be very low. Too high a dosage of Recombinant FSH may lead to hyperstimulation of the ovaries

Store at 2°C-8°C (in refrigerator). Do not keep in deep freeze. Keep out of reach of children.