thyrotropin alfa (Rx)

>10%

Nausea (11%)

1-10%

Headache (6%)

Fatigue (2%)

Vomiting (2%)

Dizziness (2%)

Asthenia (1%)

Postmarketing Reports

Pain

Erythema

Bruising

Pruritus

Contraindications

None

Cautions

Warnings and precautions of radioiodine (RAI) apply if added in combination regimen; see warnings and precautions for RAI when used in combination

Known to cause a transient (over 7 to 14 days) but significant rise in serum thyroid hormone concentration when given to patients who have substantial thyroid tissue still in situ or functional thyroid cancer metastases

Sudden, rapid and painful tumor enlargement reported

CHF, hypopituitarism, concurrent use of corticosteroids

Anaphylactic reaction may occur after repeated use of thyrotropin

Radioiodine testing 24 hr after final thyrotropin dose

Reports of death within 24 hr after administration; patients for whom thyrotropin-induced hyperthyroidism could have serious consequences (eg, heart disease, extensive metastatic disease), consider hospitalization for administration and postadministration observation

Reports of neurologic events, including acute hemiplegia or hemiparesis, occurring 1-3 days after administration to patients with CNS metastases; these events associated with sudden rapid tumor enlargement

Postmarketing reports of stroke or unilateral weakness occurring within 72 hr (range 20 minutes to 3 days) of administration to women without known CNS metastases

Tumor enlargement that is sudden, rapid and painful reported within 12-48 hr of administration; symptoms include dyspnea, stridor, or dysphonia; rapid clinical improvement occurred following glucocorticoid therapy (consider pretreatment with glucocorticoids if local tumor expansion may compromise vital anatomic structures)

Use caution in patients with known history of heart disease

Pregnancy

Drug may be used in combination with radioiodine (RAI); if drug is administered with RAI, combination regimen is contraindicated in pregnant women because fetal exposure to RAI can lead to neonatal hypothyroidism, which in some cases is severe and irreversible; refer to RAI prescribing information for more information on use during pregnancy

Available data from case reports and postmarketing experience with use in pregnant women are insufficient to evaluate for a drug-associated risk of major birth defects, miscarriage, or adverse maternal or fetal outcomes; animal reproduction studies have not been conducted with drug

Reproductive potential

• If drug is administered with RAI, the information for RAI regarding pregnancy testing, contraception, and infertility also applies to combination regimen; refer to RAI prescribing information for additional information

Lactation

The concomitant use of drug and therapeutic radioiodine (RAI) is contraindicated in lactating women because RAI concentrates in breast tissue and increases risk of radiation breast toxicity (refer to therapeutic RAI Prescribing Information).

If drug is administered with RAI for diagnostic use, discontinue breastfeeding after RAI administration because of potential for serious adverse reactions from RAI in breastfed infant (refer to diagnostic RAI Prescribing Information)

If drug is not administered with RAI, developmental and health benefits of breastfeeding should be considered along with mother’s clinical need for drug and any potential adverse effects on breastfed child from drug or from underlying maternal condition

There are no available data on presence of thyrotropin alfa in human milk, effects on breastfed infant, or on milk production

Pregnancy Categories

A: Generally acceptable. Controlled studies in pregnant women show no evidence of fetal risk.

B: May be acceptable. Either animal studies show no risk but human studies not available or animal studies showed minor risks and human studies done and showed no risk.

C: Use with caution if benefits outweigh risks. Animal studies show risk and human studies not available or neither animal nor human studies done.

D: Use in LIFE-THREATENING emergencies when no safer drug available. Positive evidence of human fetal risk.

X: Do not use in pregnancy. Risks involved outweigh potential benefits. Safer alternatives exist.

NA: Information not available.

Mechanism of Action

Recombinant thyroid stimulating hormone (TSH); increases iodine uptake by thyroid & formation, secretion, or release of thyroid hormones; stimulates the secretion of Tg from any remaining thyroid tissue remenants; elevated Tg levels suggest the presence of remmnant thyroid tissues

Pharmacokinetics

Half-life: 15-35 hr

Peak plasma time: 3-24 hr after injection

IM Preparation

Add 1.2 mL of sterile water for injection to the vial containing lyophilized powder

Do not shake the solution; swirl the contents of the vial until all the material is dissolved

Reconstituted solution concentration is 0.9 mg/mL

IM Administration

Visually inspect the reconstituted solution for particulate matter and discoloration prior to administration; it should be clear and colorless (do not use if particulate matter present, or solution is cloudy or discolored)

Inject 1 mL (0.9 mg) IM in the buttocks

Discard unused portions

Do not mix with other substances

Storage

Protect from light

Refrigerate at 2-8ºC (36-46ºF)

Reconstituted vial

• Room temperature: Use within 3 hr
• Refrigerated (2-8ºC [36-46ºF]): Use within 24 hr