Fulvestrant Injection
FDA Label NDC 68462-317

Monotherapy

Fulvestrant injection 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.

Monotherapy

The recommended dose of fulvestrant injection is 500 mg to be administered intramuscularly into the buttocks (gluteal area) slowly (1 to 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)].

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 to 2 minutes) as one 5 mL injection on Days 1, 15, 29, and once monthly thereafter.

Fulvestrant injection 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)].

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 fulvestrant injection at the dorsogluteal injection site [see Warnings and Precautions (5.3) and Adverse Reactions (6.1)].

The proper method of administration of fulvestrant injection for intramuscular use is described in the following instructions.

For each single-dose pre-filled 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 TWIST THE CAP COUNTER-CLOCKWISE 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).

Figure-2 (Figure 2)

7. 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.

Figure-3 (Figure 3)

For Administration:

8. Pull shield straight off needle to avoid damaging needle point.

9. Remove needle sheath.

10. Expel excess gas from the syringe (a small gas bubble may remain).

11. Administer intramuscularly slowly (1 to 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.

Figure-4 (Figure 4)

12. 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.

Figure-5 (Figure 5)

13. Discard the empty syringe into an approved sharps collector in accordance with applicable regulations and institutional policy.

14. Repeat steps 1 through 13 for second syringe.

How To Use Fulvestrant Injection

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.

Important Administration Information

To help avoid HIV (AIDS), HBV (Hepatitis), and other infectious diseases due to accidental needle sticks, contaminated needles should not be recapped or removed, unless there is no alternative or that such action is required by a specific medical procedure. Hands must remain behind the needle at all times during use and disposal.

Do not autoclave SafetyGlide^TM Needle before use.

Becton Dickinson guarantees the contents of their unopened or undamaged packages to be sterile, non-toxic, and non-pyrogenic.

Fulvestrant injection, an injection for intramuscular administration, is supplied as 5 mL single-dose pre-filled syringes containing 250 mg/5 mL fulvestrant.

Fulvestrant 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 [see Adverse Reactions (6.2)].

Because fulvestrant injection is administered intramuscularly, it should be used with caution in patients with bleeding diatheses, thrombocytopenia, or anticoagulant use.

The safety and pharmacokinetics of fulvestrant 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)].

Fulvestrant has not been studied in patients with severe hepatic impairment (Child-Pugh class C) [see Use in Specific Populations (8.6)].

Injection site related events including sciatica, neuralgia, neuropathic pain, and peripheral neuropathy have been reported with fulvestrant injection. Caution should be taken while administering fulvestrant 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)].

Based on findings from animal studies and its mechanism of action, fulvestrant 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 fulvestrant and for one year after the last dose [see Use in Specific Populations (8.1), (8.3) and Clinical Pharmacology (12.1)].

Due to structural similarity of fulvestrant and estradiol, fulvestrant can interfere with estradiol measurement by immunoassay, resulting in falsely elevated estradiol levels.

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)]

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 Fulvestrant 500 mg and Fulvestrant 250 mg (CONFIRM)

The following adverse reactions (ARs) were calculated based on the safety analysis of CONFIRM comparing the administration of fulvestrant 500 mg intramuscularly once a month with fulvestrant 250 mg intramuscularly once a month. The most frequently reported adverse reactions in the fulvestrant 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 fulvestrant 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)

¹Including more severe injection site related sciatica, neuralgia, neuropathic pain, and peripheral neuropathy.

In the pooled safety population (N = 1127) from clinical trials comparing fulvestrant 500 mg to fulvestrant 250 mg, post-baseline increases of ≥ 1 CTC grade in either AST, ALT, or alkaline phosphatase were observed in > 15% of patients receiving fulvestrant. Grade 3 to 4 increases were observed in 1 to 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 fulvestrant arms.

Comparison of Fulvestrant 500 mg and Anastrozole 1 mg (FALCON)

The safety of fulvestrant 500 mg versus anastrozole 1 mg was evaluated in FALCON. The data described below reflect exposure to fulvestrant 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 fulvestrant and in 3 of 232 (1.3%) patients receiving anastrozole. Adverse reactions leading to discontinuation for those patients receiving fulvestrant 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 fulvestrant arm were arthralgia, hot flash, fatigue, and nausea.

Adverse reactions reported in patients who received fulvestrant 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

Table 3: Laboratory Abnormalities in FALCON¹

¹In FALCON, post-baseline increases of ≥ 1 CTC grade in either AST, ALT, or alkaline phosphatase were observed in > 10% of patients receiving Fulvestrant. Grade 3 to 4 increases were observed in 1% to 3% of patients.

Comparison of Fulvestrant 250 mg and Anastrozole 1 mg in Combined Trials (Studies 0020 and 0021)

The most commonly reported adverse reactions in the fulvestrant 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 fulvestrant 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 fulvestrant 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 fulvestrant 250 mg intramuscularly once a month with anastrozole 1 mg orally once a day.

Table 4: Adverse Reactions in Studies 0020 and 0021 (≥ 5% from Combined Data)

¹Including more severe injection site related sciatica, neuralgia, neuropathic pain, and peripheral neuropathy. All patients on fulvestrant received injections, but only those anastrozole patients who were in Study 0021 received placebo injections.

For fulvestrant 250 mg, other adverse reactions reported as drug-related and seen infrequently (< 1%) include thromboembolic phenomena, myalgia, vertigo, leukopenia, and hypersensitivity reactions, including angioedema and urticaria.

Vaginal bleeding has been reported infrequently (< 1%), mainly in patients during the first 6 weeks after changing from existing hormonal therapy to treatment with fulvestrant. If bleeding persists, further evaluation should be considered.

Elevation of bilirubin, elevation of gamma GT, hepatitis, and liver failure have been reported infrequently (< 1%).

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)].

Risk Summary

Based on findings from animal studies and its mechanism of action, fulvestrant 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/m², 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 to 4% and 15 to 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/m². 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/m²) 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/m²) 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/m²). Further, at 0.25 mg/kg/day (30% the human dose based on mg/m²), 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/m²) when administered during the period of organogenesis.

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 fulvestrant, advise a lactating woman not to breastfeed during treatment with fulvestrant 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/m²) during lactation, offspring survival was slightly reduced.

Pregnancy Testing

Pregnancy testing is recommended for females of reproductive potential within seven days prior to initiating fulvestrant.

Contraception

Females

Fulvestrant 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, fulvestrant 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)].

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 ± 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 fulvestrant 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 fulvestrant. 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 fulvestrant. 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.

For fulvestrant 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 in Study 0021 and Study 0020, respectively.

Fulvestrant is metabolized primarily in the liver.

The pharmacokinetics of fulvestrant were evaluated after a single dose of 100 mg in subjects with mild and moderate hepatic impairment and normal hepatic function (n = 7 subjects/group), using a shorter-acting intramuscular injection formulation. Subjects with mild hepatic impairment (Child-Pugh class A) had comparable mean AUC and clearance values to those with normal hepatic function. In subjects with moderate hepatic impairment (Child-Pugh class B), the average AUC of fulvestrant increased by 70% compared to patients with normal hepatic function. AUC was positively correlated with total bilirubin concentration (p = 0.012). Fulvestrant has not been studied in patients with severe hepatic impairment (Child-Pugh class C).

A dose of fulvestrant 250 mg is recommended in patients with moderate hepatic impairment (Child- Pugh class B) [see Dosage and Administration (2.2) and Warnings and Precautions (5.2)].

Negligible amounts of fulvestrant are eliminated in urine; therefore, a study in patients with renal impairment was not conducted. In the advanced breast cancer trials, fulvestrant concentrations in women with estimated creatinine clearance as low as 30 mL/min were similar to women with normal creatinine.

Human experience of overdose with fulvestrant is limited. There are isolated reports of overdose with fulvestrant 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.

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 C₃₂H₄₇F₅O₃S and its structural formula is:

Structure (Structure)

Fulvestrant is a white powder with a molecular weight of 606.77 g/mol. The solution for injection is a clear, colorless to yellow, viscous liquid.

Each injection contains as inactive ingredients: 12% v/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.

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 uterotropic 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.

In a clinical study in postmenopausal women with primary breast cancer treated with single doses of fulvestrant 15 to 22 days prior to surgery, there was evidence of increasing down-regulation of ER with increasing dose. This was associated with a dose-related decrease in the expression of the progesterone receptor, an estrogen-regulated protein. These effects on the ER pathway were also associated with a decrease in Ki67 labeling index, a marker of cell proliferation.

Absorption:

The single dose and multiple dose PK parameters for the 500 mg dosing regimen with an additional dose (AD) at Day 15 are reported in Table 11. The additional dose of fulvestrant given two weeks after the initial dose allows for steady state concentrations to be reached within the first month of dosing.

Table 11: Summary of Fulvestrant Pharmacokinetic Parameters [gMean (CV%)] in Postmenopausal Advanced Breast Cancer Patients after Intramuscular Administration 500 mg + AD Dosing Regimen

¹Additional 500 mg dose given on Day 15

²Month 3

Distribution:

The apparent volume of distribution at steady state is approximately 3 to 5 L/kg. This suggests that distribution is largely extravascular. Fulvestrant is highly (99%) bound to plasma proteins; VLDL, LDL, and HDL lipoprotein fractions appear to be the major binding components. The role of sex hormone-binding globulin, if any, could not be determined.

Metabolism:

Biotransformation and disposition of fulvestrant in humans have been determined following intramuscular and intravenous administration of ¹⁴C -labeled fulvestrant. Metabolism of fulvestrant appears to involve combinations of a number of possible biotransformation pathways analogous to those of endogenous steroids, including oxidation, aromatic hydroxylation, conjugation with glucuronic acid and/or sulphate at the 2, 3, and 17 positions of the steroid nucleus, and oxidation of the side chain sulphoxide. Identified metabolites are either less active or exhibit similar activity to fulvestrant in antiestrogen models.

Studies using human liver preparations and recombinant human enzymes indicate that cytochrome P-450 3A4 (CYP 3A4) is the only P-450 isoenzyme involved in the oxidation of fulvestrant; however, the relative contribution of P-450 and non-P-450 routes in vivo is unknown.

Excretion:

Fulvestrant was rapidly cleared by the hepatobiliary route with excretion primarily via the feces (approximately 90%). Renal elimination was negligible (less than 1%). After an intramuscular injection of 250 mg, the clearance (Mean ± SD) was 690 ± 226 mL/min with an apparent half-life about 40 days.

Special Populations:

Geriatric:

In patients with breast cancer, there was no difference in fulvestrant pharmacokinetic profile related to age (range 33 to 89 years).

Gender:

Following administration of a single intravenous dose, there were no pharmacokinetic differences between men and women or between premenopausal and postmenopausal women. Similarly, there were no differences between men and postmenopausal women after intramuscular administration.

Race:

In the advanced breast cancer treatment trials, the potential for pharmacokinetic differences due to race have been evaluated in 294 women including 87.4% Caucasian, 7.8% Black, and 4.4% Hispanic. No differences in fulvestrant plasma pharmacokinetics were observed among these groups. In a separate trial, pharmacokinetic data from postmenopausal ethnic Japanese women were similar to those obtained in non-Japanese patients.

Drug-Drug Interactions:

There are no known drug-drug interactions. Fulvestrant does not significantly inhibit any of the major CYP isoenzymes, including CYP 1A2, 2C9, 2C19, 2D6, and 3A4 in vitro, and studies of co-administration of fulvestrant with midazolam indicate that therapeutic doses of fulvestrant have no inhibitory effects on CYP 3A4 or alter blood levels of drug metabolized by that enzyme. Although fulvestrant is partly metabolized by CYP 3A4, a clinical study with rifampin, an inducer of CYP 3A4, showed no effect on the pharmacokinetics of fulvestrant. Also, results from a healthy volunteer study with ketoconazole, a potent inhibitor of CYP 3A4, indicated that ketoconazole had no effect on the pharmacokinetics of fulvestrant and dosage adjustment is not necessary in patients co-prescribed CYP 3A4 inhibitors or inducers [see Drug Interactions (7)].

Two-year carcinogenesis studies were conducted in rats and mice. Positive findings were observed in both species. Rats were treated at intramuscular doses of 15 mg/kg/30 days, 10 mg/rat/30 days, and 10 mg/rat/15 days.

These doses correspond to 0.9-, 1.5-, and 3-fold (in females) and 0.8-, 0.8-, and 2-fold (in males) the systemic exposure [AUC_{0 to 30} days] achieved in women receiving the recommended dose of 500 mg/month. An increased incidence of benign ovarian granulosa cell tumors and testicular Leydig cell tumors was evident, in females dosed at 10 mg/rat/15 days and males dosed at 15 mg/rat/30 days, respectively. Mice were treated at oral doses of 0, 20, 150, and 500 mg/kg/day. These doses correspond to 0, 0.8, 8.4, and 18-fold (in females) and 0.8-, 7.1-, and 11.9-fold (in males), the systemic exposure (AUC_{0 to 30} days) achieved in women receiving the recommended dose of 500 mg/month. There was an increased incidence of sex cord stromal tumors (both benign and malignant) in the ovary of mice at doses of 150 and 500 mg/kg/day. Induction of such tumors is consistent with the pharmacology-related endocrine feedback alterations in gonadotropin levels caused by an antiestrogen.

Fulvestrant was not mutagenic or clastogenic in multiple in vitro tests with and without the addition of a mammalian liver metabolic activation factor (bacterial mutation assay in strains of Salmonella typhimurium and Escherichia coli, in vitro cytogenetics study in human lymphocytes, mammalian cell mutation assay in mouse lymphoma cells, and in vivo micronucleus test in rat).

In female rats, fulvestrant administered at doses ≥ 0.01 mg/kg/day (0.6% the human recommended dose based on body surface area [BSA in mg/m²]), for 2 weeks prior to and for 1 week following mating, caused a reduction in fertility and embryonic survival. No adverse effects on female fertility and embryonic survival were evident in female animals dosed at 0.001 mg/kg/day (0.06% the human dose based on BSA in mg/m²). Restoration of female fertility to values similar to controls was evident following a 29-day withdrawal period after dosing at 2 mg/kg/day (equivalent to the human dose based on BSA in mg/m²). The effects of fulvestrant on the fertility of female rats appear to be consistent with its antiestrogenic activity. The potential effects of fulvestrant on the fertility of male animals were not studied, but in a 6-month toxicology study, male rats treated with intramuscular doses of 15 mg/kg/30 days, 10 mg/rat/30 days, or 10 mg/rat/15 days fulvestrant showed a loss of spermatozoa from the seminiferous tubules, seminiferous tubular atrophy, and degenerative changes in the epididymides. Changes in the testes and epididymides had not recovered 20 weeks after cessation of dosing. These fulvestrant doses correspond to 1.3-, 1.2-, and 3.5-fold the systemic exposure [AUC_{0 to 30} days] achieved in women receiving the recommended dose of 500 mg/month.

The efficacy of fulvestrant 500 mg versus fulvestrant 250 mg was compared in CONFIRM. The efficacy of fulvestrant 250 mg was compared to 1 mg anastrozole in Studies 0020 and 0021. The efficacy of fulvestrant 500 mg was compared to 1 mg anastrozole in FALCON.

Monotherapy

Comparison of Fulvestrant 500 mg and Fulvestrant 250 mg (CONFIRM)

A randomized, double-blind, controlled clinical trial (CONFIRM, NCT00099437) was completed in 736 postmenopausal women with advanced breast cancer who had disease recurrence on or after adjuvant endocrine therapy or progression following endocrine therapy for advanced disease. This trial compared the efficacy and safety of fulvestrant 500 mg (n=362) with fulvestrant 250 mg (n=374).

Fulvestrant 500 mg was administered as two 5 mL injections each containing fulvestrant 250 mg/5 mL, one in each buttock, on Days 1, 15, 29 and every 28 (+/-3) days thereafter. Fulvestrant 250 mg was administered as two 5 mL injections (one containing fulvestrant 250 mg/5 mL injection plus one placebo injection), one in each buttock, on Days 1, 15 (2 placebo injections only), 29, and every 28 (+/-3) days thereafter.

The median age of study participants was 61 years. All patients had ER+ advanced breast cancer. Approximately 30% of subjects had no measurable disease. Approximately 55% of patients had visceral disease.

Results of CONFIRM are summarized in Table 12. The efficacy of fulvestrant 500 mg was compared to that of fulvestrant 250 mg. Figure 6 shows a Kaplan-Meier plot of the Progression Free Survival (PFS) data after a minimum follow-up duration of 18 months demonstrating statistically significant superiority of fulvestrant 500 mg vs. fulvestrant 250 mg. In the initial Overall Survival (OS) analysis after a minimum follow-up duration of 18 months, there was no statistically significant difference in OS between the two treatment groups. After a minimum follow-up duration of 50 months, an updated OS analysis was performed. Figure 7 shows a Kaplan-Meier plot of the updated OS data.

Table 12: Efficacy Results in CONFIRM (Intent-To-Treat (ITT) Population)

¹PFS (Progression Free Survival) = the time between randomization and the earliest of progression or death from any cause. Minimum follow-up duration of 18 months.

²Hazard Ratio <1 favors fulvestrant 500 mg.

³CI=Confidence Interval

⁴OS=Overall Survival

⁵Minimum follow up duration of 50 months.

⁶Not statistically significant as no adjustments were made for multiplicity.

⁷ORR (Objective Response Rate), as defined as number (%) of patients with complete response or partial response, was analyzed in the evaluable patients with measurable disease at baseline (fulvestrant 500 mg N=240; fulvestrant 250 mg N=261). Minimum follow-up duration of 18 months.

Figure 6 Kaplan-Meier PFS: CONFIRM ITT Population

Figure-6 (Figure 6)

Figure 7 Kaplan-Meier OS (Minimum Follow-up Duration of 50 Months): CONFIRM ITT Population

Figure7 (Figure7)

Comparison of Fulvestrant 500 mg and Anastrozole 1 mg (FALCON)

A randomized, double-blind, double-dummy, multi-center study (FALCON, NCT01602380) of fulvestrant 500 mg versus anastrozole 1 mg was conducted in postmenopausal women with ER-positive and/or PgR-positive, HER2-negative locally advanced or metastatic breast cancer who had not previously been treated with any hormonal therapy. A total of 462 patients were randomized 1:1 to receive administration of fulvestrant 500 mg as an intramuscular injection on Days 1, 15, 29, and every 28 (+/-3) days thereafter or daily administration of 1 mg of anastrozole orally. This study compared the efficacy and safety of fulvestrant 500 mg and anastrozole 1 mg.

Randomization was stratified by disease setting (locally advanced or metastatic), use of prior chemotherapy for advanced disease, and presence or absence of measurable disease.

The major efficacy outcome measure of the study was investigator-assessed progression-free survival (PFS) evaluated according to RECIST v.1.1 (Response Evaluation Criteria in Solid Tumors). Key secondary efficacy outcome measures included overall survival (OS), objective response rate (ORR), and duration of response (DoR).

Patients enrolled in this study had a median age of 63 years (range 36 to 90). The majority of patients (87%) had metastatic disease at baseline. Fifty-five percent (55%) of patients had visceral metastasis at baseline. A total of 17% of patients had received one prior chemotherapy regimen for advanced disease; 84% of patients had measurable disease. Sites of metastases were as follows: musculoskeletal 59%, lymph nodes 50%, respiratory 40%, liver (including gall bladder) 18%.

The efficacy results of FALCON are presented in Table 13 and Figure 8.

Table 13: Efficacy Results in FALCON (Investigator Assessment, ITT Population)

NR: Not reached

¹Interim OS analysis with 61% of total number of events required for the final OS analysis.

Figure 8 Kaplan-Meier Plot of Progression-Free Survival (Investigator Assessment, ITT Population) ─ FALCON

Figure-8 (Figure 8)

Comparison of Fulvestrant 250 mg and Anastrozole 1 mg in Combined Data (Studies 0020 and 0021)

Efficacy of fulvestrant was established by comparison to the selective aromatase inhibitor anastrozole in two randomized, controlled clinical trials (one conducted in North America, Study 0021, NCT00635713; the other predominantly in Europe, Study 0020) in postmenopausal women with locally advanced or metastatic breast cancer. All patients had progressed after previous therapy with an antiestrogen or progestin for breast cancer in the adjuvant or advanced disease setting.

The median age of study participants was 64 years. 81.6% of patients had ER+ and/or PgR+ tumors. Patients with ER-/PgR-or unknown tumors were required to have demonstrated a prior response to endocrine therapy. Sites of metastases occurred as follows: visceral only 18.2%; viscera – liver involvement 23%; lung involvement 28.1%; bone only 19.7%; soft tissue only 5.2%; skin and soft tissue 18.7%.

In both trials, eligible patients with measurable and/or evaluable disease were randomized to receive either fulvestrant 250 mg intramuscularly once a month (28 days + 3 days) or anastrozole 1 mg orally once a day. All patients were assessed monthly for the first three months and every three months thereafter. Study 0021 was a double-blind, randomized trial in 400 postmenopausal women. Study 0020 was an open-label, randomized trial conducted in 451 postmenopausal women. Patients on the fulvestrant arm of Study 0021 received two separate injections (2 x 2.5 mL), whereas fulvestrant patients received a single injection (1 x 5 mL) in Study 0020. In both trials, patients were initially randomized to a 125 mg per month dose as well, but interim analysis showed a very low response rate, and low dose groups were dropped.

Results of the trials, after a minimum follow-up duration of 14.6 months, are summarized in Table 14. The effectiveness of fulvestrant 250 mg was determined by comparing Objective Response Rate (ORR) and Time to Progression (TTP) results to anastrozole 1 mg, the active control. The two studies ruled out (by one-sided 97.7% confidence limit) inferiority of fulvestrant to anastrozole of 6.3% and 1.4% in terms of ORR. There was no statistically significant difference in overall survival (OS) between the two treatment groups after a follow-up duration of 28.2 months in Study 0021 and 24.4 months in Study 0020.

Table 14: Efficacy Results in Studies 0020 and 0021 (Objective Response Rate (ORR) and Time to Progression (TTP))

¹CR = Complete Response

²PR = Partial Response

³FAS = FULVESTRANT

⁴ANA = anastrozole

⁵CI = Confidence Interval

⁶Hazard Ratio < 1 favors FULVESTRANT

Fulvestrant Injection is supplied as two 5 mL clear neutral glass (Type 1) barrels, each containing 250 mg/5 mL of fulvestrant solution for intramuscular injection and fitted with a tamper evident closure.

NDC 68462–317–32

The single-dose pre-filled 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°C to 8°C (36°F to 46°F). TO PROTECT FROM LIGHT, STORE IN THE ORIGINAL CARTON UNTIL TIME OF USE.

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 (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 fulvestrant 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 fulvestrant and for one year after the last dose [see Use in Specific Populations (8.2)].

Manufactured by:

Ajinomoto Althea, Inc.
San Diego, CA 92121


Manufactured for:



Logo (Logo)

 Glenmark Pharmaceuticals Inc., USA
 Mahwah, NJ 07430
Questions? 1 (888) 721-7115
www.glenmarkpharma.com/usa
May 2019

Fulvestrant (ful ves’ trant)

injection

What is Fulvestrant injection?

Fulvestrant injection is a prescription medicine used to treat advanced breast cancer or breast cancer that has spread to other parts of the body (metastatic).

Fulvestrant injection may be used alone, if you have gone through menopause, and your advanced breast cancer is:

• hormone receptor (HR)-positive and human epidermal growth factor receptor 2 (HER2)-negative and has not been previously treated with endocrine therapy
•  or
• HR-positive and has progressed after endocrine therapy.
•  It is not known if fulvestrant injection is safe and effective in children.
•  It is not known if fulvestrant injection is safe and effective in people with severe liver problems.

Who should not receive Fulvestrant injection?

Do not receive fulvestrant injection if you have had an allergic reaction to fulvestrant or any of the ingredients in fulvestrant injection. See the end of this leaflet for a list of the ingredients in fulvestrant injection.

Symptoms of an allergic reaction to fulvestrant injection may include:

• itching or hives
• swelling of your face, lips, tongue, or throat
• trouble breathing

What should I tell my healthcare provider before receiving fulvestrant injection?

Before receiving fulvestrant injection, tell your healthcare provider about all of your medical conditions, including if you:

• have a low level of platelets in your blood or bleed easily.
• have liver problems.
• are pregnant or plan to become pregnant. Fulvestrant can harm your unborn baby.
•  Females who are able to become pregnant:
• Your healthcare provider may perform a pregnancy test within 7 days before you start fulvestrant injection.
• You should use effective birth control during treatment with fulvestrant injection and for one year after the last dose of fulvestrant injection.
• Tell your healthcare provider right away if you become pregnant or think you are pregnant during treatment with fulvestrant injection.
• are breastfeeding or plan to breastfeed. It is not known if fulvestrant passes into your breast milk. Do not breastfeed during your treatment with fulvestrant injection and for one year after the final dose of fulvestrant injection. Talk to your healthcare provider about the best way to feed your baby during this time.

Tell your healthcare provider about all the medicines you take, including prescription and over-the-counter medicines, vitamins, and herbal supplements. Fulvestrant injection may affect the way other medicines work, and other medicines may affect how fulvestrant injection works.

Especially tell your healthcare provider if you take a blood thinner medicine.

How will I receive Fulvestrant injection?

• Your healthcare provider will give you fulvestrant by injection into the muscle of each buttock.
• Your healthcare provider may change your dose of fulvestrant if needed.

What are the possible side effects of Fulvestrant injection?

Fulvestrant injection may cause serious side effects, including:

• Injection site related nerve damage. Call your healthcare provider if you develop any of the following symptoms in your legs following a fulvestrant injection:
• numbness
• tingling
• weakness

The most common side effects of fulvestrant injection include:

injection site pain nausea muscle, joint, and bone pain headache back pain tiredness pain in arms, hands, legs, or feet hot flashes

vomiting loss of appetite weakness cough shortness of breath constipation increased liver enzymes diarrhea

Fulvestrant may cause fertility problems in males and females. Talk to your healthcare provider if you plan to become pregnant.

Tell your healthcare provider if you have any side effect that bothers you or that does not go away.

These are not all of the possible side effects with fulvestrant injection. For more information, ask your healthcare provider or pharmacist.

Call your healthcare provider for medical advice about side effects. You may report side effects to FDA at 1-800-FDA-1088.

You may also report side effects to Glenmark Pharmaceuticals Inc., USA at 1 (888) 721-7115.

General information about the safe and effective use of Fulvestrant injection

Medicines are sometimes prescribed for purposes other than those listed in a Patient Information leaflet. If you would like more information, talk with your healthcare provider. You can ask your pharmacist or healthcare provider for information about fulvestrant injection that is written for health professionals.

What are the ingredients in fulvestrant injection?

Active ingredient: fulvestrant.

Inactive ingredients: alcohol, benzyl alcohol, benzyl benzoate, and castor oil.

SafetyGlide™ is a trademark of Becton Dickinson and Company.

Manufactured by:

Ajinomoto Althea, Inc.
San Diego, CA 92121


Manufactured for:



Logo (Logo)

Glenmark Pharmaceuticals Inc., USA
Mahwah, NJ 07430
Questions? 1 (888) 721-7115
www.glenmarkpharma.com/usa

This Patient Information has been approved by the U.S. Food and Drug Administration

May 2019

NDC 68462-317-32
Fulvestrant Injection
250 mg/5 mL (50 mg/mL)