Fulvestrant

Intramuscular
Estrogen receptor positive locally advanced breast cancer in postmenopausal women, Estrogen receptor positive metastatic breast cancer in postmenopausal women

Intramuscular
Hormone receptor positive, HER2-negative locally advanced carcinoma of breast, Hormone receptor positive, HER2-negative metastatic carcinoma of breast

Intramuscular
Hormone receptor positive, HER2-negative locally advanced breast cancer in postmenopausal women, Hormone receptor positive, HER2-negative metastatic breast cancer in postmenopausal women

Moderate (Child-Pugh Class B): 250 mg (into 1 buttock) on days 1, 15, and 29, then once monthly thereafter. Severe: Contraindicated.

Severe hepatic impairment. Pregnancy and lactation.

Patient with bleeding diatheses, thrombocytopenia. Administration at dorsogluteal injection site. Mild to moderate hepatic and severe renal (CrCl <30 mL/min) impairment.

Significant: Hypersensitivity reactions (e.g. angioedema, urticaria), injection site-related events (e.g. neuropathic pain, peripheral neuropathy, sciatica, neuralgia), thromboembolic events, risk of osteoporosis.
Gastrointestinal disorders: Nausea, vomiting, diarrhoea.
General disorders and administration site conditions: Asthenia.
Investigations: Increased ALT, AST, ALP, bilirubin.
Metabolism and nutrition disorders: Anorexia.
Musculoskeletal and connective tissue disorders: Joint and musculoskeletal pain, back pain.
Nervous system disorders: Headache, vertigo.
Renal and urinary disorders: UTI.
Reproductive system and breast disorders: Vaginal haemorrhage.
Skin and subcutaneous tissue disorders: Rash.
Vascular disorders: Hot flushes.

Monitor LFT, signs and symptoms of bleeding. Perform pregnancy test within 7 days prior to initiation.

Increased risk of bleeding with anticoagulants.

May interfere with estradiol immunoassay, resulting in falsely elevated estradiol levels.

Description: Fulvestrant competitively binds to estrogen receptors on tumours, forming a nuclear complex, causing down-regulation of estrogen receptor protein levels and inhibition of tumour growth.
Pharmacokinetics:
Absorption: Slowly absorbed. Time to peak plasma concentration: Approx 7 days.
Distribution: Extensively and rapidly distributed, primarily into the extravascular space. Volume of distribution: Approx 3-5 L/kg. Plasma protein binding: 99%, mainly to LDL, VLDL, and HDL fractions.
Metabolism: Metabolised mainly in the liver via multiple pathways to form several metabolites.
Excretion: Mainly via faeces (approx 90%); urine (<1%). Elimination half-life: Approx 40-50 days.

Source: National Center for Biotechnology Information. PubChem Database. Fulvestrant, CID=104741, https://pubchem.ncbi.nlm.nih.gov/compound/Fulvestrant (accessed on Jan. 21, 2020)

Store between 2-8°C. Protect from light.

Cancer Hormone Therapy

L02BA03 - fulvestrant ; Belongs to the class of anti-estrogens. Used in treatment of neoplastic diseases.

Anon. Fulvestrant. Lexicomp Online. Hudson, Ohio. Wolters Kluwer Clinical Drug Information, Inc. https://online.lexi.com. Accessed 04/11/2020.

Buckingham R (ed). Fulvestrant. Martindale: The Complete Drug Reference [online]. London. Pharmaceutical Press. https://www.medicinescomplete.com. Accessed 04/11/2020.

Faslodex 250 mg Solution for Injection (AstraZeneca UK Limited). National Pharmaceutical Regulatory Agency - Ministry of Health Malaysia. https://www.npra.gov.my/. Accessed 04/11/2020.

Faslodex Injection (AstraZeneca Pharmaceuticals LP). DailyMed. Source: U.S. National Library of Medicine. https://dailymed.nlm.nih.gov/dailymed/. Accessed 04/11/2020.

Fulvestrant 250 mg Solution for Injection in Pre-Filled Syringe (Genus Pharmaceuticals [Trading as Stada]). MHRA. https://products.mhra.gov.uk/. Accessed 04/11/2020.

Joint Formulary Committee. Fulvestrant. British National Formulary [online]. London. BMJ Group and Pharmaceutical Press. https://www.medicinescomplete.com. Accessed 04/11/2020.