FULVESTRANT-AFT

What it is

FULVESTRANT-AFT is a fulvestrant injection containing 250 mg/5 mL of fulvestrant drug substance. The solution for injection is a clear, colourless to yellow, viscous liquid. Fulvestrant is an antioestrogen that binds to oestrogen receptors in a competitive manner, with a high affinity comparable to that of oestradiol, and downregulates the oestrogen receptor.

Approved indications —

Hormone receptor positive, human epidermal growth factor receptor 2 negative, locally advanced or metastatic breast cancer in postmenopausal women who have not been previously treated with endocrine therapy. — Hormone receptor positive, locally advanced or metastatic breast cancer in postmenopausal women who have progressive disease following prior endocrine (anti-oestrogen or aromatase inhibitor) therapy.

Dosing overview

The recommended dose of 500 mg is administered intramuscularly as two 5 mL injections, one in each buttock, at intervals of 1 month, with an additional 500 mg dose given 2 weeks after the initial dose. The injection is recommended to be administered slowly over 1–2 minutes per injection.

Key safety warnings

There are no long-term data on the effect of fulvestrant on bone, and due to the mechanism of action of fulvestrant, there is a potential risk of osteoporosis. Caution should be used before treating patients with bleeding diatheses or thrombocytopenia or patients on anticoagulants due to the route of administration. Thromboembolic events are commonly observed in women with advanced breast cancer and have been observed in clinical studies with fulvestrant, and this should be taken into consideration when prescribing fulvestrant to patients at risk. Injection site related events including sciatica, neuralgia, neuropathic pain, and peripheral neuropathy have been reported with FULVESTRANT-AFT injection, and caution should be taken while administering FULVESTRANT-AFT at the dorsogluteal injection site due to the proximity of the underlying sciatic nerve. Fulvestrant injection has been commonly associated with elevation of liver enzymes, the vast majority less than 2 times the upper limit of normal.

Contraindications

FULVESTRANT-AFT is contraindicated in patients with a known hypersensitivity to the drug substance or to any of the excipients. FULVESTRANT-AFT is contraindicated in pregnancy and lactation. FULVESTRANT-AFT is contraindicated in severe hepatic impairment.

PBS listing

No information on PBS listing is provided in the source documents.

Regulatory history

FULVESTRANT-AFT (fulvestrant 250 mg/5 mL solution for injection pre-filled syringe) was first registered on the Australian Register of Therapeutic Goods on 5 April 2023.