Faslodex
Fulvestrant · Injection · Intramuscular
Uses
Monotherapy FASLODEX is 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, or
• HR-positive advanced breast cancer in postmenopausal women with disease progression following endocrine therapy. Combination Therapy FASLODEX is indicated for the treatment of:
• 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.
• HR-positive, HER2-negative advanced or metastatic breast cancer in combination with palbociclib or abemaciclib in women with disease progression after endocrine therapy. FASLODEX 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. (1)
• HR-positive, HER2-negative advanced or metastatic breast cancer in combination with palbociclib or abemaciclib in women with disease progression after endocrine therapy. (1)
Dosage and administration
• FASLODEX 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. ( 2.1 , 14 )
• 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. ( 2.2 , 5.2 , 8.6 ) 2.1 Recommended Dose Monotherapy The recommended dose of FASLODEX 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 (14) ] . Combination Therapy When FASLODEX is used in combination with palbociclib, abemaciclib, or ribociclib, the recommended dose of FASLODEX 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 FASLODEX 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. When FASLODEX is used in combination with abemaciclib, the recommended dose of abemaciclib is 150 mg orally, twice daily. Abemaciclib may be taken with or without food. Refer to the Full Prescribing Information for abemaciclib. When FASLODEX is used in combination with ribociclib, the recommended dose of ribociclib is 600 mg taken orally, once daily for 21 consecutive days followed by 7 days off treatment resulting in a complete cycle of 28 days. Ribociclib can be taken with or without food. Refer to the Full Prescribing Information for ribociclib. Pre/perimenopausal women treated with the combination of FASLODEX plus palbociclib, abemaciclib, or ribociclib, should be treated with luteinizing hormone-releasing hormone (LHRH) agonists according to current clinical practice standards [see Clinical Studies (14) ] . 2.2 Dose Modification Monotherapy Hepatic Impairment: A dose of 250 mg is recommended for patients with moderate hepatic impairment (Child-Pugh class B) 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. FASLODEX has not been evaluated in patients with severe hepatic impairment (Child-Pugh class C) [see Warnings and Precautions (5.2) and Use in Specific Populations (8.6) ] . Combination Therapy When FASLODEX is used in combination with palbociclib, abemaciclib, or ribociclib, refer to monotherapy dose modification instructions for FASLODEX. Refer to the Full Prescribing Information of co-administered palbociclib, abemaciclib, or ribociclib for dose modification guidelines in the event of toxicities, for use with concomitant medications, and other relevant safety information. 2.3 Administration Technique Administer the injection according to the local guidelines for performing large volume intramuscular injections. NOTE: Due to the proximity of the underlying sciatic nerve, caution should be taken if administering FASLODEX at the dorsogluteal injection site [see Warnings and Precautions (5.3) and Adverse Reactions (6.1) ]. The proper method of administration of FASLODEX for intramuscular use is described in the following instructions. For each single-dose prefilled syringe: 1. Remove glass syringe barrel from tray and check that it is not damaged. 2. Remove perforated patient record label from syringe. 3. Inspect drug product in glass syringe for any visible particulate matter or discoloration prior to use. Discard if particulate matter or discoloration is present. 4. Peel open the safety needle (SafetyGlide™) outer packaging. 5. Hold the syringe upright on the ribbed part (C). With the other hand, take hold of the cap (A) and carefully tilt cap back and forth (DO NOT TWIST CAP) until the cap disconnects for removal (see Figure 1). 6. Pull the cap (A) off in a straight upward direction. DO NOT TOUCH THE STERILE SYRINGE TIP (Luer-Lok) (B) (see Figure 2). 1. Attach the safety needle to the syringe tip (Luer-Lok). Twist needle until firmly seated (see Figure 3). Confirm that the needle is locked to the Luer connector before moving or tilting the syringe out of the vertical plane to avoid spillage of syringe contents. For Administration: 1. Pull shield straight off needle to avoid damaging needle point. 2. Remove needle sheath. 3. Expel excess gas from the syringe (a small gas bubble may remain). 4. Administer intramuscularly slowly (1-2 minutes/injection) into the buttock (gluteal area). For user convenience, the needle ‘bevel up’ position is orientated to the lever arm, as shown in Figure 4. 1. After injection, immediately activate the lever arm to deploy the needle shielding by applying a single-finger stroke to the activation assisted lever arm to push the lever arm completely forward. Listen for a click. Confirm that the needle shielding has completely covered the needle (see Figure 5). NOTE: Activate away from self and others. 1. Discard the empty syringe into an approved sharps collector in accordance with applicable regulations and institutional policy. 2. Repeat steps 1 through 13 for second syringe. How To Use FASLODEX For the 2 x 5 mL syringe package, the contents of both syringes must be injected to receive the 500 mg recommended dose. SAFETYGLIDE™ INSTRUCTIONS FROM BECTON DICKINSON SafetyGlide ™ is a trademark of Becton Dickinson and Company.
Dosage forms and strengths
3 DOSAGE FORMS AND STRENGTHS FASLODEX, an injection for intramuscular administration, is supplied as 5-mL single-dose prefilled syringes containing 250 mg/5 mL fulvestrant. FASLODEX, an injection for intramuscular administration, is supplied as 250 mg/5 mL fulvestrant. (3)
Contraindications
4 CONTRAINDICATIONS FASLODEX 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 FASLODEX [see Adverse Reactions (6.2) ].
• Hypersensitivity. (4)
Warnings and precautions
• 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 FASLODEX 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. ( 5.4 , 8.1 , 8.3 )
• Immunoassay Measurement of Serum Estradiol: FASLODEX can interfere with estradiol measurement by immunoassay, resulting in falsely elevated estradiol levels. (5.5) 5.1 Risk of Bleeding Because FASLODEX is administered intramuscularly, it should be used with caution in patients with bleeding diatheses, thrombocytopenia, or anticoagulant use. 5.2 Increased Exposure in Patients with Hepatic Impairment The safety and pharmacokinetics of FASLODEX were evaluated in a study in seven subjects with moderate hepatic impairment (Child-Pugh class B) and seven subjects with normal hepatic function. Exposure was increased in patients with moderate hepatic impairment, therefore, a dose of 250 mg is recommended [see Dosage and Administration (2.2) ]. FASLODEX has not been studied in patients with severe hepatic impairment (Child-Pugh class C) [see Use in Specific Populations (8.6) ]. 5.3 Injection Site Reaction Injection site related events including sciatica, neuralgia, neuropathic pain, and peripheral neuropathy have been reported with FASLODEX injection. Caution should be taken while administering FASLODEX at the dorsogluteal injection site due to the proximity of the underlying sciatic nerve [see Dosage and Administration (2.3) and Adverse Reactions (6.1) ] . 5.4 Embryo-Fetal Toxicity Based on findings from animal studies and its mechanism of action, FASLODEX can cause fetal harm when administered to a pregnant woman. In animal reproduction studies, administration of fulvestrant to pregnant rats and rabbits during organogenesis resulted in embryo-fetal toxicity at daily doses that are significantly less than the maximum recommended human dose. Advise pregnant women of the potential risk to a fetus. Advise females of reproductive potential to use effective contraception during treatment with FASLODEX and for one year after the last dose [see Use in Specific Populations (8.1) , (8.3) and Clinical Pharmacology (12.1) ] . 5.5 Immunoassay Measurement of Serum Estradiol Due to structural similarity of fulvestrant and estradiol, FASLODEX can interfere with estradiol measurement by immunoassay, resulting in falsely elevated estradiol levels.
Side effects
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 FASLODEX 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. (6.1)
• Increased hepatic enzymes (ALT, AST, ALP) occurred in >15% of FASLODEX patients and were not dose-dependent. (6.1) To report SUSPECTED ADVERSE REACTIONS, contact AstraZeneca at 1-800-236-9933 or FDA at 1-800-FDA-1088 or www.fda.gov/medwatch . 6.1 Clinical Trials Experience Because clinical trials are conducted under widely varying conditions, the adverse reaction rates observed cannot be directly compared to rates in other trials and may not reflect the rates observed in clinical practice. Monotherapy Comparison of FASLODEX 500 mg and FASLODEX 250 mg (CONFIRM) The following adverse reactions (ARs) were calculated based on the safety analysis of CONFIRM comparing the administration of FASLODEX 500 mg intramuscularly once a month with FASLODEX 250 mg intramuscularly once a month. The most frequently reported adverse reactions in the FASLODEX 500 mg group were injection site pain (11.6% of patients), nausea (9.7% of patients), and bone pain (9.4% of patients); the most frequently reported adverse reactions in the FASLODEX 250 mg group were nausea (13.6% of patients), back pain (10.7% of patients), and injection site pain (9.1% of patients). Table 1 lists adverse reactions reported with an incidence of 5% or greater, regardless of assessed causality, from CONFIRM. Table 1: Adverse Reactions in CONFIRM (≥5% in Either Treatment Group) Adverse Reactions FASLODEX 500 mg N=361 % FASLODEX 250 mg N=374 % Body as a Whole Injection Site Pain Including more severe injection site related sciatica, neuralgia, neuropathic pain, and peripheral neuropathy. 12 9 Headache 8 7 Back Pain 8 11 Fatigue 8 6 Pain in Extremity 7 7 Asthenia 6 6 Vascular System Hot Flash 7 6 Digestive System Nausea 10 14 Vomiting 6 6 Anorexia 6 4 Constipation 5 4 Musculoskeletal System Bone Pain 9 8 Arthralgia 8 8 Musculoskeletal Pain 6 3 Respiratory System Cough 5 5 Dyspnea 4 5 In the pooled safety population (N=1127) from clinical trials comparing FASLODEX 500 mg to FASLODEX 250 mg, post-baseline increases of ≥1 CTC grade in either AST, ALT, or alkaline phosphatase were observed in >15% of patients receiving FASLODEX. Grade 3-4 increases were observed in 1-2% of patients. The incidence and severity of increased hepatic enzymes (ALT, AST, ALP) did not differ between the 250 mg and the 500 mg FASLODEX arms. Comparison of FASLODEX 500 mg and Anastrozole 1 mg (FALCON) The safety of FASLODEX 500 mg versus anastrozole 1 mg was evaluated in FALCON. The data described below reflect exposure to FASLODEX in 228 out of 460 patients with HR-positive advanced breast cancer in postmenopausal women not previously treated with endocrine therapy who received at least one (1) dose of treatment in FALCON. Permanent discontinuation associated with an adverse reaction occurred in 4 of 228 (1.8%) patients receiving FASLODEX and in 3 of 232 (1.3%) patients receiving anastrozole. Adverse reactions leading to discontinuation for those patients receiving FASLODEX included drug hypersensitivity (0.9%), injection site hypersensitivity (0.4%), and elevated liver enzymes (0.4%). The most common adverse reactions (≥10%) of any grade reported in patients in the FASLODEX arm were arthralgia, hot flash, fatigue, and nausea. Adverse reactions reported in patients who received FASLODEX in FALCON at an incidence of ≥5% in either treatment arm are listed in Table 2, and laboratory abnormalities are listed in Table 3. Table 2: Adverse Reactions in FALCON Adverse Reactions FASLODEX 500 mg N=228 Anastrozole 1 mg N=232 All Grades % Grade 3 or 4 % All Grades % Grade 3 or 4 % Vascular Disorders Hot flash 11 0 10 0 Gastrointestinal Disorders Nausea 11 0 10 <1 Diarrhea 6 0 6 <1 Musculoskeletal and Connective Tissue Disorders Arthralgia 17 0 10 0 Myalgia 7 0 3 0 Pain in extremity 6 0 4 0 Back pain 9 <1 6 0 General Disorders and Administration Site Conditions Fatigue 11 <1 7 <1 Table 3: Laboratory Abnormalities in FALCON In FALCON, post-baseline increases of ≥1 CTC grade in either AST, ALT, or alkaline phosphatase were observed in >10% of patients receiving FASLODEX. Grade 3-4 increases were observed in 1%-3% of patients. Laboratory Parameters FASLODEX 500 mg N=228 Anastrozole 1 mg N=232 All Grades % Grade 3 or 4 % All Grades % Grade 3 or 4 % Alanine aminotransferase increased (ALT) 7 1 3 0 Aspartate aminotransferase increased (AST) 5 1 3 <1 Comparison of FASLODEX 250 mg and Anastrozole 1 mg in Combined Trials (Studies 0020 and 0021) The most commonly reported adverse reactions in the FASLODEX and anastrozole treatment groups were gastrointestinal symptoms (including nausea, vomiting, constipation, diarrhea, and abdominal pain), headache, back pain, vasodilatation (hot flashes), and pharyngitis. Injection site reactions with mild transient pain and inflammation were seen with FASLODEX and occurred in 7% of patients given the single 5 mL injection (Study 0020) and in 27% of patients given the 2 x 2.5 mL injections (Study 0021) in the two clinical trials that compared FASLODEX 250 mg and anastrozole 1 mg. Table 4 lists adverse reactions reported with an incidence of 5% or greater, regardless of assessed causality, from the two controlled clinical trials comparing the administration of FASLODEX 250 mg intramuscularly once a month with anastrozole 1 mg orally once a day.
Drug interactions
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)
Use in specific populations
• Lactation: Advise not to breastfeed. (8.2) 8.1 Pregnancy Risk Summary Based on findings from animal studies and its mechanism of action, FASLODEX 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. In animal reproduction studies, administration of fulvestrant to pregnant rats and rabbits during organogenesis caused embryo-fetal toxicity, including skeletal malformations and fetal loss, at daily doses that were 6% and 30% of the maximum recommended human dose based on mg/m 2 , respectively [see Data] . Advise pregnant women of the potential risk to a fetus. The estimated background risk of major birth defects and miscarriage for the indicated population is unknown. In the U.S. general population, the estimated background risk of major birth defects and miscarriage in clinically recognized pregnancies is 2-4% and 15-20%, respectively. Data Animal Data Administration of fulvestrant to rats prior to and up to implantation caused embryonic loss at daily doses that were 0.6% of the daily maximum recommended human dose based on mg/m 2 . When fulvestrant was administered to pregnant rats during the period of organogenesis, intramuscular doses ≥0.1 mg/kg/day (6% of the human recommended dose based on mg/m 2 ) caused effects on embryo-fetal development consistent with its antiestrogenic activity. Fulvestrant caused an increased incidence of fetal abnormalities in rats (tarsal flexure of the hind paw at 2 mg/kg/day; equivalent to the human dose based on mg/m 2 ) and non-ossification of the odontoid and ventral tubercle of the first cervical vertebra at doses ≥0.1 mg/kg/day. Fulvestrant administered at 2 mg/kg/day caused fetal loss. When administered to pregnant rabbits during the period of organogenesis, fulvestrant caused pregnancy loss at an intramuscular dose of 1 mg/kg/day (equivalent to the human dose based on mg/m 2 ). Further, at 0.25 mg/kg/day (30% the human dose based on mg/m 2 ), fulvestrant caused increases in placental weight and post-implantation loss in rabbits. Fulvestrant was associated with an increased incidence of fetal variations in rabbits (backwards displacement of the pelvic girdle, and 27 pre-sacral vertebrae at 0.25 mg/kg/day; 30% the human dose based on mg/m 2 ) when administered during the period of organogenesis. 8.2 Lactation Risk Summary There is no information regarding the presence of fulvestrant in human milk, nor of its effects on milk production or breastfed infant. Fulvestrant can be detected in rat milk [see Data] . Because of the potential for serious adverse reactions in breastfed infants from FASLODEX, advise a lactating woman not to breastfeed during treatment with FASLODEX and for one year after the final dose. Data Levels of fulvestrant were approximately 12-fold higher in milk than in plasma after exposure of lactating rats to a dose of 2 mg/kg. Drug exposure in rodent pups from fulvestrant-treated lactating dams was estimated as 10% of the administered dose. In a study in rats of fulvestrant at 10 mg/kg given twice or 15 mg/kg given once (less than the recommended human dose based on mg/m 2 ) during lactation, offspring survival was slightly reduced. 8.3 Females and Males of Reproductive Potential Pregnancy Testing Pregnancy testing is recommended for females of reproductive potential within seven days prior to initiating FASLODEX. Contraception Females FASLODEX can cause fetal harm when administered to a pregnant woman [see Use in Specific Populations (8.1) ] . Advise females of reproductive potential to use effective contraception during treatment and for one year after the last dose. Infertility Based on animal studies, FASLODEX may impair fertility in females and males of reproductive potential. The effects of fulvestrant on fertility were reversible in female rats [see Nonclinical Toxicology (13.1) ]. 8.4 Pediatric Use 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. Baseline measurements for vaginal bleeding days, bone age, growth velocity, and Tanner staging for at least 6 months prior to study entry were provided retrospectively by the parent, guardian, or local consultant. All measurements during the study period were collected prospectively. Patients’ baseline characteristics included the following: a mean ± SD chronological age of 5.9 ± 1.8 years; a mean rate of bone age advancement (change in bone age in years divided by change in chronological age in years) of 2.0 ± 1.03; and a mean growth velocity z-score of 2.4 ± 3.26. Twenty-nine of 30 patients completed the 12-month study period. The following results were observed: 35% (95% CI: 16%, 57%) of the 23 patients with baseline vaginal bleeding experienced a complete cessation of vaginal bleeding on-treatment (month 0 to 12); a reduction in the rate of bone age advancement during the 12-month study period compared to baseline (mean change=-0.9 [95% CI: -1.4, -0.4]); and a reduction in mean growth velocity Z-score on-treatment compared to baseline (mean change=-1.1 [95% CI: -2.7, 0.4]). There were no clinically meaningful changes in median Tanner stage (breast or pubic), mean uterine volume, or mean ovarian volume, or predicted adult height (PAH) on-treatment compared to baseline. The effect of FASLODEX on bone mineral density in children has not been studied and is not known.
Pregnancy
8.1 Pregnancy Risk Summary Based on findings from animal studies and its mechanism of action, FASLODEX 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. In animal reproduction studies, administration of fulvestrant to pregnant rats and rabbits during organogenesis caused embryo-fetal toxicity, including skeletal malformations and fetal loss, at daily doses that were 6% and 30% of the maximum recommended human dose based on mg/m 2 , respectively [see Data] . Advise pregnant women of the potential risk to a fetus. The estimated background risk of major birth defects and miscarriage for the indicated population is unknown. In the U.S. general population, the estimated background risk of major birth defects and miscarriage in clinically recognized pregnancies is 2-4% and 15-20%, respectively. Data Animal Data Administration of fulvestrant to rats prior to and up to implantation caused embryonic loss at daily doses that were 0.6% of the daily maximum recommended human dose based on mg/m 2 . When fulvestrant was administered to pregnant rats during the period of organogenesis, intramuscular doses ≥0.1 mg/kg/day (6% of the human recommended dose based on mg/m 2 ) caused effects on embryo-fetal development consistent with its antiestrogenic activity. Fulvestrant caused an increased incidence of fetal abnormalities in rats (tarsal flexure of the hind paw at 2 mg/kg/day; equivalent to the human dose based on mg/m 2 ) and non-ossification of the odontoid and ventral tubercle of the first cervical vertebra at doses ≥0.1 mg/kg/day. Fulvestrant administered at 2 mg/kg/day caused fetal loss. When administered to pregnant rabbits during the period of organogenesis, fulvestrant caused pregnancy loss at an intramuscular dose of 1 mg/kg/day (equivalent to the human dose based on mg/m 2 ). Further, at 0.25 mg/kg/day (30% the human dose based on mg/m 2 ), fulvestrant caused increases in placental weight and post-implantation loss in rabbits. Fulvestrant was associated with an increased incidence of fetal variations in rabbits (backwards displacement of the pelvic girdle, and 27 pre-sacral vertebrae at 0.25 mg/kg/day; 30% the human dose based on mg/m 2 ) when administered during the period of organogenesis.
Pediatric use
8.4 Pediatric Use 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. Baseline measurements for vaginal bleeding days, bone age, growth velocity, and Tanner staging for at least 6 months prior to study entry were provided retrospectively by the parent, guardian, or local consultant. All measurements during the study period were collected prospectively. Patients’ baseline characteristics included the following: a mean ± SD chronological age of 5.9 ± 1.8 years; a mean rate of bone age advancement (change in bone age in years divided by change in chronological age in years) of 2.0 ± 1.03; and a mean growth velocity z-score of 2.4 ± 3.26. Twenty-nine of 30 patients completed the 12-month study period. The following results were observed: 35% (95% CI: 16%, 57%) of the 23 patients with baseline vaginal bleeding experienced a complete cessation of vaginal bleeding on-treatment (month 0 to 12); a reduction in the rate of bone age advancement during the 12-month study period compared to baseline (mean change=-0.9 [95% CI: -1.4, -0.4]); and a reduction in mean growth velocity Z-score on-treatment compared to baseline (mean change=-1.1 [95% CI: -2.7, 0.4]). There were no clinically meaningful changes in median Tanner stage (breast or pubic), mean uterine volume, or mean ovarian volume, or predicted adult height (PAH) on-treatment compared to baseline. The effect of FASLODEX on bone mineral density in children has not been studied and is not known. Eight patients (27%) experienced adverse reactions that were considered possibly related to FASLODEX. These included injection site reactions (inflammation, pain, hematoma, pruritus, rash), abdominal pain, contusion, tachycardia, hot flash, extremity pain, and vomiting. Nine (30%) patients reported an SAE, none of which were considered related to FASLODEX. No patients discontinued study treatment due to an AE and no patients died. Pharmacokinetics The pharmacokinetics of fulvestrant was characterized using a population pharmacokinetic analysis with sparse samples per patient obtained from 30 female pediatric patients aged 1 to 8 years with PPP associated with MAS. Pharmacokinetic data from 294 postmenopausal women with breast cancer who received 125 or 250 mg monthly dosing regimen were also included in the analysis. In these pediatric patients receiving 4 mg/kg monthly intramuscular dose of fulvestrant, the geometric mean (SD) CL/F was 444 (165) mL/min which was 32% lower than adults. The geometric mean (SD) steady state trough concentration (C min,ss ) and AUC ss was 4.19 (0.87) ng/mL and 3680 (1020) ng*hr/mL, respectively.
Geriatric use
8.5 Geriatric Use For FASLODEX 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 FASLODEX in Study 0021 and Study 0020, respectively.
Overdosage
Human experience of overdose with FASLODEX is limited. There are isolated reports of overdose with FASLODEX 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. There is no specific treatment in the event of fulvestrant overdose, and symptoms of overdose are not established. In the event of an overdose, healthcare practitioners should follow general supportive measures and should treat symptomatically.
Description
11 DESCRIPTION FASLODEX ® (fulvestrant) injection for intramuscular administration is an estrogen receptor antagonist. The chemical name is 7-alpha-[9-(4,4,5,5,5-penta fluoropentylsulphinyl) nonyl]estra-1,3,5-(10)- triene-3,17-beta-diol. The molecular formula is C 32 H 47 F 5 O 3 S and its structural formula is: Fulvestrant is a white powder with a molecular weight of 606.77. The solution for injection is a clear, colorless to yellow, viscous liquid. Each injection contains as inactive ingredients: 10% w/v Alcohol, USP, 10% w/v Benzyl Alcohol, NF, and 15% w/v Benzyl Benzoate, USP, as co-solvents, and made up to 100% w/v with Castor Oil, USP as a co-solvent and release rate modifier. Chemical Structure
Mechanism of action
12.1 Mechanism of Action Many breast cancers have estrogen receptors (ER) and the growth of these tumors can be stimulated by estrogen. Fulvestrant is an estrogen receptor antagonist that binds to the estrogen receptor in a competitive manner with affinity comparable to that of estradiol and downregulates the ER protein in human breast cancer cells. In vitro studies demonstrated that fulvestrant is a reversible inhibitor of the growth of tamoxifen-resistant, as well as estrogen-sensitive human breast cancer (MCF-7) cell lines. In in vivo tumor studies, fulvestrant delayed the establishment of tumors from xenografts of human breast cancer MCF-7 cells in nude mice. Fulvestrant inhibited the growth of established MCF-7 xenografts and of tamoxifen-resistant breast tumor xenografts. Fulvestrant showed no agonist-type effects in in vivo uterotrophic assays in immature or ovariectomized mice and rats. In in vivo studies in immature rats and ovariectomized monkeys, fulvestrant blocked the uterotrophic action of estradiol. In postmenopausal women, the absence of changes in plasma concentrations of FSH and LH in response to fulvestrant treatment (250 mg monthly) suggests no peripheral steroidal effects.
How supplied
16 HOW SUPPLIED/STORAGE AND HANDLING FASLODEX is supplied as two 5 mL clear neutral glass (Type 1) barrels, each containing 250 mg/5 mL of FASLODEX solution for intramuscular injection and fitted with a tamper evident closure. NDC 0310–0720–10 The single-dose prefilled syringes are presented in a tray with polystyrene plunger rod and safety needles (SafetyGlide™) for connection to the barrel. Discard each syringe after use. If a patient dose requires only one syringe, unused syringe should be stored as directed below. Storage: REFRIGERATE, 2°-8°C (36°-46°F). TO PROTECT FROM LIGHT, STORE IN THE ORIGINAL CARTON UNTIL TIME OF USE .
Patient information
Advise the patient to read the FDA-approved patient labeling (Patient Information). Monotherapy Risk of Bleeding:
• Because FASLODEX 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 (5.1) ]. Embryo-Fetal Toxicity:
• Advise females of reproductive potential of the potential risk to a fetus and to use effective contraception during treatment with FASLODEX and for one year after the last dose. Advise females to inform their healthcare provider of a known or suspected pregnancy [see Warnings and Precautions (5.4) and Use in Specific Populations (8.1) , (8.3) ]. Lactation:
• Advise women not to breastfeed during treatment with FASLODEX and for one year after the last dose [see Use in Specific Populations (8.2) ] . Combination Therapy When FASLODEX is used in combination with palbociclib, abemaciclib, or ribociclib, refer to the respective Full Prescribing Information for Patient Counseling Information. Distributed by: AstraZeneca Pharmaceuticals LP Wilmington, DE 19850 FASLODEX is a registered trademark of the AstraZeneca group of companies ©AstraZeneca 2020
Label text from the FDA structured product label by AstraZeneca Pharmaceuticals LP (revised Sep 25, 2020). Long sections are shortened; the complete label is on DailyMed.
Active ingredients
- Fulvestrant in 1 product
Faslodex NDC products (1)
| NDC | Strength & form | Labeler | Type |
|---|---|---|---|
| 0310-0720 | Fulvestrant 50 mg/mL Injection | AstraZeneca Pharmaceuticals LP | NDA |
Frequently asked questions
What is Faslodex used for?
Monotherapy FASLODEX is 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, or • HR-positive advanced breast cancer in postmenopausal women with disease progression following endocrine therapy. Combination Therapy FASLODEX is…
What are the side effects of Faslodex?
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… See the full label for the complete list.
Who makes Faslodex?
Faslodex is listed by 1 labeler in the FDA NDC directory, including AstraZeneca Pharmaceuticals LP.