Enzalutamide

FDA Drug Information • Also known as: Xtandi

Brand Names
Xtandi
Dosage Form
TABLET
Product Type
DRUG FOR FURTHER PROCESSING

Description

11 DESCRIPTION Enzalutamide is an androgen receptor inhibitor. The chemical name is 4-{3-[4-cyano-3-(trifluoromethyl)phenyl]-5,5-dimethyl-4-oxo-2-sulfanylideneimidazolidin-1-yl}-2-fluoro- N -methylbenzamide. The molecular weight is 464.44 and molecular formula is C 21 H 16 F 4 N 4 O 2 S. The structural formula is: Enzalutamide is a white crystalline non-hygroscopic solid. It is practically insoluble in water. XTANDI is available as liquid-filled soft gelatin capsules for oral administration. Each capsule contains 40 mg of enzalutamide as a solution in caprylocaproyl polyoxylglycerides. The inactive ingredients are caprylocaproyl polyoxylglycerides, butylated hydroxyanisole, butylated hydroxytoluene, gelatin, sorbitol sorbitan solution, glycerin, purified water, titanium dioxide, and black iron oxide. XTANDI is also available as film-coated tablets for oral administration. Each tablet contains 40 mg or 80 mg of enzalutamide. The inactive ingredients are hypromellose acetate succinate, microcrystalline cellulose, colloidal silicon dioxide, croscarmellose sodium, and magnesium stearate. The tablet film-coat contains hypromellose, talc, polyethylene glycol, titanium dioxide, and ferric oxide. Structural formula of Enzalutamide

What Is Enzalutamide Used For?

1 INDICATIONS AND USAGE XTANDI ® is indicated for the treatment of patients with:

  • castration-resistant prostate cancer (CRPC)
  • metastatic castration-sensitive prostate cancer (mCSPC)
  • non‑metastatic castration‑sensitive prostate cancer (nmCSPC) with biochemical recurrence at high risk for metastasis (high-risk BCR) XTANDI is an androgen receptor inhibitor indicated for the treatment of patients with:
  • castration-resistant prostate cancer. ( 1 )
  • metastatic castration-sensitive prostate cancer. ( 1 )
  • non‑metastatic castration‑sensitive prostate cancer with biochemical recurrence at high risk for metastasis. ( 1 )

  • Dosage and Administration

    2 DOSAGE AND ADMINISTRATION

  • Take XTANDI 160 mg administered orally once daily with or without food. ( 2.1 )
  • Advise patients to take each capsule or tablet whole with a sufficient amount of water to ensure that all medication is successfully swallowed. ( 2.1 , 5.7 )
  • Patients receiving XTANDI for castration-resistant prostate cancer, or metastatic castration sensitive prostate cancer should also receive a gonadotropin-releasing hormone (GnRH) analog concurrently or should have had bilateral orchiectomy. ( 2.1 )
  • Patients with non-metastatic castration-sensitive prostate cancer with biochemical recurrence at high risk for metastasis may be treated with or without a GnRH analog. ( 2.1 ) 2.1 Recommended Dosage The recommended dosage of XTANDI is 160 mg administered orally once daily with or without food [see Clinical Pharmacology ( 12.3 )] until disease progression or unacceptable toxicity. Advise patients to take each capsule or tablet whole with a sufficient amount of water to ensure that all medication is successfully swallowed. Do NOT chew, dissolve, or open the capsules. Do NOT cut, crush, or chew the tablets. Patients with CRPC or mCSPC receiving XTANDI should also receive a gonadotropic-releasing hormone (GnRH) analog concurrently or should have had bilateral orchiectomy. Patients with nmCSPC with high-risk BCR may be treated with XTANDI with or without a GnRH analog. For patients who receive XTANDI with or without a GnRH analog, treatment can be suspended if PSA is undetectable (< 0.2 ng/mL) after 36 weeks of therapy. Reinitiate treatment when PSA has increased to ≥ 2.0 ng/mL for patients who had prior radical prostatectomy or ≥ 5.0 ng/mL for patients who had prior primary radiation therapy [see Clinical Studies ( 14 )] . 2.2 Dosage Modifications for Adverse Reactions If a patient experiences a ≥ Grade 3 or an intolerable adverse reaction, withhold XTANDI for one week or until symptoms improve to ≤ Grade 2, then resume at the same or a reduced dose (120 mg or 80 mg) if warranted [see Warnings and Precautions ( 5.1 , 5.2 )] . 2.3 Dosage Modifications for Drug Interactions Strong CYP2C8 Inhibitors Avoid the coadministration of strong CYP2C8 inhibitors. If the coadministration of a strong CYP2C8 inhibitor cannot be avoided, reduce the XTANDI dosage to 80 mg once daily. If the coadministration of the strong inhibitor is discontinued, increase the XTANDI dosage to the dosage used prior to initiation of the strong CYP2C8 inhibitor [see Clinical Pharmacology ( 12.3 )]. Strong CYP3A4 Inducers Avoid the coadministration of strong CYP3A4 inducers. If the coadministration of a strong CYP3A4 inducer cannot be avoided, increase the XTANDI dosage from 160 mg to 240 mg orally once daily. If the coadministration of the strong CYP3A4 inducer is discontinued, decrease the XTANDI dosage to the dosage used prior to initiation of the strong CYP3A4 inducer [see Clinical Pharmacology ( 12.3 )].

  • Side Effects (Adverse Reactions)

    6 ADVERSE REACTIONS The following is discussed in more detail in other sections of the labeling:

  • Seizure [see Warnings and Precautions ( 5.1 )]
  • Posterior Reversible Encephalopathy Syndrome (PRES) [see Warnings and Precautions ( 5.2 )]
  • Hypersensitivity [see Warnings and Precautions ( 5.3 )]
  • Ischemic Heart Disease [see Warnings and Precautions ( 5.4 )]
  • Falls and Fractures [see Warnings and Precautions ( 5.5 )]
  • Dysphagia or Choking [see Warnings and Precautions ( 5.7 )] The most common adverse reactions (≥ 10%) that occurred more frequently (≥ 2% over placebo) in the XTANDI-treated patients are musculoskeletal pain, fatigue, hot flush, constipation, decreased appetite, diarrhea, hypertension, hemorrhage, fall, fracture, and headache. ( 6.1 ) To report SUSPECTED ADVERSE REACTIONS, contact Astellas Pharma US, Inc. at 1-800-727-7003 or FDA at 1-800-FDA-1088 or www.fda.gov/medwatch . 6.1 Clinical Trial Experience Because clinical trials are conducted under widely varying conditions, adverse reaction rates observed in the clinical trials of a drug cannot be directly compared to rates in the clinical trials of another drug and may not reflect the rates observed in practice. The data in WARNINGS and PRECAUTIONS reflect eight randomized, controlled trials [AFFIRM, PREVAIL, TERRAIN, PROSPER, ARCHES, EMBARK, Asian PREVAIL (NCT02294461), and STRIVE (NCT01664923)] that were pooled to conduct safety analyses in patients with CRPC (N = 3651), mCSPC (N = 752), or nmCSPC with high‑risk BCR (N = 707) treated with XTANDI. Patients received XTANDI 160 mg (N = 5110) or placebo orally once daily (N = 2829) or bicalutamide 50 mg orally once daily (N = 387). In these eight trials, the median duration of treatment was 22.1 months (range: < 0.1 to 95.0) in patients that received XTANDI. In five placebo-controlled trials (AFFIRM, PROSPER, PREVAIL, ARCHES, and EMBARK), the median duration of treatment was 19.4 months (range: < 0.1 to 90.4) in the XTANDI group [see Clinical Studies ( 14 )]. In these five trials, the most common adverse reactions (≥ 10%) that occurred more frequently (≥ 2% over placebo) in the XTANDI-treated patients were musculoskeletal pain, fatigue, hot flush, constipation, decreased appetite, diarrhea, hypertension, hemorrhage, fall, fracture and headache. AFFIRM: XTANDI versus Placebo in Metastatic CRPC Following Chemotherapy AFFIRM enrolled 1199 patients with metastatic CRPC who had previously received docetaxel. The median duration of treatment was 8.3 months with XTANDI and 3.0 months with placebo. During the trial, 48% of patients on the XTANDI arm and 46% of patients on the placebo arm received glucocorticoids. Grade 3 and higher adverse reactions were reported among 47% of XTANDI-treated patients. Discontinuations due to adverse reactions were reported for 16% of XTANDI-treated patients. The most common adverse reaction leading to treatment discontinuation was seizure, which occurred in 0.9% of the XTANDI-treated patients compared to none (0%) of the placebo-treated patients. Table 1 shows adverse reactions reported in AFFIRM that occurred at a ≥ 2% higher frequency in the XTANDI arm compared to the placebo arm. Table 1. Adverse Reactions in AFFIRM XTANDI (N = 800) Placebo (N = 399) Grade 1-4 CTCAE v 4. (%) Grade 3-4 (%) Grade 1-4 (%) Grade 3-4 (%) General Disorders Asthenic Conditions Includes asthenia and fatigue. 51 9 44 9 Peripheral Edema 15 1 13 0.8 Musculoskeletal and Connective Tissue Disorders Back Pain 26 5 24 4 Arthralgia 21 2.5 17 1.8 Musculoskeletal Pain 15 1.3 12 0.3 Muscular Weakness 10 1.5 7 1.8 Musculoskeletal Stiffness 2.6 0.3 0.3 0 Gastrointestinal Disorders Diarrhea 22 1.1 18 0.3 Vascular Disorders Hot Flush 20 0 10 0 Hypertension 6 2.1 2.8 1.3 Nervous System Disorders Headache 12 0.9 5 0 Dizziness Includes dizziness and vertigo. 9 0.5 7 0.5 Spinal Cord Compression and Cauda Equina Syndrome 7 7 4.5 3.8 Paresthesia 7 0 4.5 0 Mental Impairment Disorders Includes amnesia, memory impairment, cognitive...

  • Drug Interactions

    7 DRUG INTERACTIONS

  • Strong CYP2C8 Inhibitors: Avoid strong CYP2C8 inhibitors. If coadministration cannot be avoided, reduce the dosage of XTANDI. ( 2.3 , 7.1 )
  • Strong CYP3A4 Inducers: Avoid strong CYP3A4 inducers. If coadministration cannot be avoided, increase the dosage of XTANDI. ( 2.3 , 7.1 )
  • Avoid coadministration with certain CYP3A4, CYP2C9, or CYP2C19 substrates for which a minimal decrease in concentration may lead to therapeutic failure of the substrate. In cases where active metabolites are formed, there may be increased exposure to the active metabolites. ( 7.2 ) 7.1 Effect of Other Drugs on XTANDI Strong CYP2C8 Inhibitors The coadministration of XTANDI with gemfibrozil (a strong CYP2C8 inhibitor) increases plasma concentrations of enzalutamide plus N-desmethyl enzalutamide, which may increase the incidence and severity of adverse reactions of XTANDI. Avoid the coadministration of XTANDI with strong CYP2C8 inhibitors. If the coadministration of XTANDI with a strong CYP2C8 inhibitor cannot be avoided, reduce the dosage of XTANDI [see Dosage and Administration ( 2.3 ), Clinical Pharmacology ( 12.3 )]. Strong CYP3A4 Inducers The coadministration of XTANDI with rifampin (a strong CYP3A4 inducer and a moderate CYP2C8 inducer) decreases plasma concentrations of enzalutamide plus N-desmethyl enzalutamide, which may decrease the efficacy of XTANDI. Avoid the coadministration of XTANDI with strong CYP3A4 inducers. If the coadministration of XTANDI with a strong CYP3A4 inducer cannot be avoided, increase the dosage of XTANDI [see Dosage and Administration ( 2.3 ), Clinical Pharmacology ( 12.3 )]. 7.2 Effect of XTANDI on Other Drugs Certain CYP3A4, CYP2C9, or CYP2C19 Substrates XTANDI is a strong CYP3A4 inducer and a moderate CYP2C9 and CYP2C19 inducer. The coadministration of XTANDI decreases the concentrations of certain CYP3A4, CYP2C9, or CYP2C19 substrates [see Clinical Pharmacology ( 12.3 )] , which may reduce the efficacy of these substrates. Avoid the coadministration of XTANDI with certain CYP3A4, CYP2C9, or CYP2C19 substrates for which a minimal decrease in concentration may lead to therapeutic failure of the substrate. If the coadministration cannot be avoided, increase the dosage of these substrates in accordance with their Prescribing Information. In cases where active metabolites are formed, there may be increased exposure to the active metabolites. 7.3 Laboratory Test Interference XTANDI can interfere with certain digoxin immunoassays (e.g., Chemiluminescent Microparticle Immunoassays), resulting in falsely elevated digoxin plasma concentration results. Notify the laboratory conducting the digoxin plasma concentration assay to use an appropriate method in patients receiving XTANDI and digoxin [see Warnings and Precautions ( 5.8 )] .

  • Contraindications

    4 CONTRAINDICATIONS None. None. ( 4 )

    Pregnancy and Breastfeeding

    8.1 Pregnancy Risk Summary The safety and efficacy of XTANDI have not been established in females. Based on animal reproductive studies and mechanism of action, XTANDI can cause fetal harm and loss of pregnancy. There are no human data on the use of XTANDI in pregnant females. In animal reproduction studies, oral administration of enzalutamide in pregnant mice during organogenesis caused adverse developmental effects at doses lower than the maximum recommended human dose (see Data). Data Animal Data In an embryo-fetal developmental toxicity study in mice, enzalutamide caused developmental toxicity when administered at oral doses of 10 or 30 mg/kg/day throughout the period of organogenesis (gestational days 6-15). Findings included embryo-fetal lethality (increased post-implantation loss and resorptions) and decreased anogenital distance at ≥ 10 mg/kg/day, and cleft palate and absent palatine bone at 30 mg/kg/day. Doses of 30 mg/kg/day caused maternal toxicity. The doses tested in mice (1, 10 and 30 mg/kg/day) resulted in systemic exposures (AUC) approximately 0.04, 0.4 and 1.1 times, respectively, the exposures in patients. Enzalutamide did not cause developmental toxicity in rabbits when administered throughout the period of organogenesis (gestational days 6-18) at dose levels up to 10 mg/kg/day (approximately 0.4 times the exposures in patients based on AUC). In a pharmacokinetic study in pregnant rats with a single oral 30 mg/kg enzalutamide administration on gestation day 14, enzalutamide and/or its metabolites were present in the fetus at a C max that was approximately 0.3 times the concentration found in maternal plasma and occurred 4 hours after administration.

    Overdosage

    10 OVERDOSAGE In the event of an overdosage, stop treatment with XTANDI and initiate general supportive measures taking into consideration the half-life of 5.8 days. In a dose escalation study, no seizures were reported at < 240 mg daily, whereas 3 seizures were reported, 1 each at 360 mg, 480 mg, and 600 mg daily. Patients may be at increased risk of seizure following an overdosage.

    How Supplied

    16 HOW SUPPLIED/STORAGE AND HANDLING XTANDI (enzalutamide) 40 mg capsules are supplied as white to off-white oblong soft gelatin capsules imprinted in black ink with ENZ and are available in the following package size:

  • Bottles of 120 capsules with child resistant closures (NDC 0469-0125-99) XTANDI (enzalutamide) 40 mg tablets are supplied as yellow, round, film-coated tablets debossed with E 40, and are available in the following package size:
  • Bottles of 120 tablets with child resistant closures (NDC 0469-0625-99) XTANDI (enzalutamide) 80 mg tablets are supplied as yellow, oval, film-coated tablets debossed with E 80, and are available in the following package size:
  • Bottles of 60 tablets with child resistant closures (NDC 0469-0725-60) Store XTANDI capsules and tablets at 20°C to 25°C (68°F to 77°F) in a dry place and keep the container tightly closed. Excursions permitted from 15°C to 30°C (59°F to 86°F).

  • About This Information

    This drug information is sourced from FDA-approved labeling via the openFDA database. It is intended for educational and reference purposes only. This is not medical advice. Always consult your healthcare provider before making decisions about medication. Drug information may be updated by the FDA; check with your pharmacist for the most current information.

    What are side effects?

    Side effects are unwanted reactions that can occur when taking a medication. They range from mild (headache, nausea) to severe (allergic reactions, organ damage). Not everyone experiences side effects, and severity varies. Report any concerning side effects to your doctor.

    What are drug interactions?

    Drug interactions occur when a medication is affected by another drug, food, or supplement. Interactions can make medications less effective or cause dangerous side effects. Always tell your doctor about all medications and supplements you take.