Fulvestrant

Fulvestrant Injection is an estrogen receptor antagonist indicated for the treatment of: Hormone receptor (HR)-positive, human epidermal growth factor receptor 2 (HER2)-negative advanced breast cancer in postmenopausal women not previously treated with endocrine therapy. ( 1 ) HR-positive advanced breast cancer in postmenopausal women with disease progression following endocrine therapy. ( 1 ) HR-positive, HER2-negative advanced or metastatic breast cancer in postmenopausal women in combination with ribociclib, as initial endocrine based therapy or following disease progression on endocrine therapy. …

• Fulvestrant Injection 500 mg should be administered intramuscularly into the buttocks (gluteal area) slowly (1 - 2 minutes per injection) as two 5 mL injections, one in each buttock, on Days 1, 15, 29, and once monthly thereafter
• A dose of 250 mg is recommended in patients with moderate hepatic impairment to be administered intramuscularly into the buttock (gluteal area) slowly (1 - 2 minutes) as one 5 mL injection on Days 1, 15, 29, and once monthly thereafter
• Recommended Dose Monotherapy The recommended dose of Fulvestrant Injection is 500 mg to be administered intramuscularly into the buttocks (gluteal area) slowly (1 - 2 minutes per injection) as two 5 mL injections, one in each buttock, on Days 1, 15, 29, and once monthly thereafter [see Clinical Studies ]
• Combination Therapy When Fulvestrant Injection is used in combination with palbociclib, abemaciclib, or ribociclib, the recommended dose of Fulvestrant Injection is 500 mg to be administered intramuscularly into the buttocks (gluteal area) slowly (1 - 2 minutes per injection) as two 5 mL injections, one in each buttock, on Days 1, 15, 29, and once monthly thereafter
• When Fulvestrant Injection is used in combination with palbociclib, the recommended dose of palbociclib is a 125 mg capsule taken orally once daily for 21 consecutive days followed by 7 days off treatment to comprise a complete cycle of 28 days
• Palbociclib should be taken with food
• Refer to the Full Prescribing Information for palbociclib. …

Fulvestrant Injection, an injection for intramuscular administration, is supplied as 5-mL single-dose prefilled syringes containing 250 mg per 5 mL fulvestrant. Fulvestrant Injection, an injection for intramuscular administration, is supplied as 250 mg per 5 mL fulvestrant. ( 3 )

• Safety and effectiveness
• In pediatric patients have not been established
• A multi-center, single-arm, open-label, study of fulvestrant was conducted in 30 girls with McCune-Albright Syndrome (MAS) associated with Progressive Precocious Puberty (PPP)
• The median age at informed consent was 6 years old (range: 1 to 8)
• The first 10 patients initially received fulvestrant 2 mg/kg
• Based on PK data from the first 6 patients, all 10 patients receiving 2 mg/kg were escalated to a dose of 4 mg/kg and all other patients received 4 mg/kg from study entry. …

For Fulvestrant Injection 250 mg, when tumor response was considered by age, objective responses were seen in 22% and 24% of patients under 65 years of age and in 11% and 16% of patients 65 years of age and older, who were treated with Fulvestrant Injection in Study 0021 and Study 0020, respectively.

• Advise the patient to read the FDA-approved patient labeling (Patient Information)
• Monotherapy Risk of Bleeding Because Fulvestrant Injection is administered intramuscularly, it should be used with caution in patients with bleeding disorders, decreased platelet count, or in patients receiving anticoagulants (for example, warfarin) [see Warnings and Precautions ]
• Embryo-Fetal Toxicity Advise females of reproductive potential of the potential risk to a fetus and to use effective contraception during treatment with Fulvestrant Injection and for one year after the last dose. …

• Fulvestrant Injection is contraindicated in patients with a known hypersensitivity to the drug or to any of its components
• Hypersensitivity reactions, including urticaria and angioedema, have been reported in association with Fulvestrant Injection [see Adverse Reactions ]
• Hypersensitivity

There are no known drug-drug interactions. Although, fulvestrant is metabolized by CYP 3A4 in vitro , drug interactions studies with ketoconazole or rifampin did not alter fulvestrant pharmacokinetics. Dose adjustment is not needed in patients co-prescribed CYP 3A4 inhibitors or inducers [see Clinical Pharmacology ( 12.3 )] . There are no known drug-drug interactions. ( 7 )

Risk of Bleeding: Use with caution in patients with bleeding diatheses, thrombocytopenia, or anticoagulant use. ( 5.1 ) Increased Exposure in Patients with Hepatic Impairment: Use a 250 mg dose for patients with moderate hepatic impairment. ( 2.2 , 5.2 , 8.6 ) Injection Site Reaction: Use caution while administering Fulvestrant Injection at the dorsogluteal injection site due to the proximity of the underlying sciatic nerve. ( 5.3 ) Embryo-Fetal Toxicity: Can cause fetal harm. Advise females of reproductive potential of the potential risk to a fetus and to use effective contraception. …

The following adverse reactions are discussed in more detail in other sections of the labeling: Risk of Bleeding [see Warnings and Precautions ( 5.1 )] Increased Exposure in Patients with Hepatic Impairment [see Warnings and Precautions ( 5.2 )] Injection Site Reaction [see Warnings and Precautions ( 5.3 )] Embryo-Fetal Toxicity [see Warnings and Precautions ( 5.4 )] The most common adverse reactions occurring in ≥5% of patients receiving Fulvestrant Injection 500 mg were: injection site pain, nausea, bone pain, arthralgia, headache, back pain, fatigue, pain in extremity, hot flash, vomiting, anorexia, asthenia, musculoskeletal pain, cough, dyspnea, and constipation. …

8.1 Pregnancy Risk Summary Based on findings from animal studies and its mechanism of action, Fulvestrant Injection can cause fetal harm when administered to a pregnant woman [see Clinical Pharmacology ( 12.1 )]. There are no available data in pregnant women to inform the drug-associated risk. …

Human experience of overdose with Fulvestrant Injection is limited. There are isolated reports of overdose with Fulvestrant Injection in humans. No adverse reactions were seen in healthy male and female volunteers who received intravenous fulvestrant, which resulted in peak plasma concentrations at the end of the infusion, that were approximately 10 to 15 times those seen after intramuscular injection. The potential toxicity of fulvestrant at these or higher concentrations in cancer patients who may have additional comorbidities is unknown. …

Storage REFRIGERATE, 2° to 8°C (36° to 46°F). TO PROTECT FROM LIGHT, STORE IN THE ORIGINAL CARTON UNTIL TIME OF USE. Sterile, Nonpyrogenic, PVC-free, DEHP-free.

Take it when you remember, unless it is nearly time for the next dose. Then skip the missed one. Never take two doses at once to make up for it. Check your leaflet, as some medicines are different.