Pharmacotherapeutic group:
anti-tumor agent, antiandrogen.
ATC code: L02BB03
Pharmacological properties:
Pharmacodynamics
Bicalutamide, an antitumor agent, is a racemic mixture with nonsteroidal antiandrogenic activity predominantly of the (R)-enantiomer, has no other endocrine activity. Bicalutamide binds to androgen receptors on the surface of target organ cells, suppressing the stimulating effects of androgens without activating gene expression. As a result, there is regression of prostate malignancy. In some patients, discontinuation of bicalutamide may lead to the development of clinical “withdrawal” syndrome of anti-androgens.
Pharmacokinetics
absorption:
After oral administration, bicalutamide is rapidly and completely absorbed from the gastrointestinal tract. Food intake does not affect the bioavailability of the drug. Time of reaching maximum concentration (TCmax) of (R)-enantiomer is 31.3 hours.
Distribution:
The binding to plasma proteins is high (for racemic mixture – 96%, for (R)-enantiomer 99%).
Metabolism:
It is extensively metabolized in the liver (by oxidation and formation of conjugates with glucuronic acid) to inactive (S)- and active (R)-enantiomers.
Elimation:
Bicalutamide is excreted as metabolites by the kidneys and with the bile in equal proportions. The (S)-enantiomer is excreted much faster than the (R)-enantiomer; the half-life (T1/2) of the latter is about 7 days.
When taking bicalutamide daily, the plasma concentration of the (R)-enantiomer increases about 10-fold due to the long T1/2, which makes it possible to take the drug once a day. When bicalutamide is taken daily in a dose of 50 mg, the equilibrium plasma concentration (Cs) of (R)-enantiomer is about 9 µg/ml.
When bicalutamide is administered at 150 mg daily, the equilibrium concentration of the (R)-enantiomer is approximately 22 µg/mL. At equilibrium, approximately 99% of all circulating enantiomers in the blood are the active (R)-enantiomer. Pharmacokinetics of the (R)-enantiomer is independent of age, renal function status, mild to moderate liver function abnormalities. There is evidence that in patients with severe hepatic impairment, excretion of (R)-enantiomer from plasma is delayed.
Indications
Prostate cancer:
Active ingredient
Composition
Active ingredient:
50 mg or 150 mg bicatulomide.
Auxiliary Substances:
Magnesium aluminosilicate,
sodium carboxymethyl starch,
magnesium stearate,
ludipress in terms of components:
lactose monohydrate,
povidone,
crospovidone.
Shell:
Opadray II Yellow 85F32771 (polyvinyl alcohol – 35.0 – 49.00%, talc 9.80 – 25.00%, macrogol 3350 – 7.35 – 35.20%, titanium dioxide and iron oxide yellow – 15.15 – 30.00%), Opadray II Yellow 85F32733 (polyvinyl alcohol – 35.0 – 49.00%, talc – 9.80 – 25.00%, macrogol 3350 – 7.35 – 35.20%, titanium dioxide and iron oxide yellow – 15.15 – 30.00%).
How to take, the dosage
Ingestion, regardless of meals, with plenty of fluids. The drug is prescribed to adult men (including elderly).
In advanced prostate cancer, oral doses of 50 mg once daily, combined with simultaneous initiation of treatment with a GnRH analogue or surgical castration.
In locally advanced non-metastatic prostate cancer, 150 mg once daily.
Bicalutamide should be taken long-term, for at least 2 years. If there are signs of disease progression, the drug should be stopped.
With impaired renal function: No dose adjustment is necessary.
Hepatic impairment: Patients with mild hepatic impairment do not require dose adjustment. In patients with moderate or severe hepatic impairment increased cumulation of bicalutamide is possible; therefore, the drug should be used with caution.
Interaction
There are no data on pharmacokinetic or pharmacodynamic interactions between bicalutamide and GnRH analogues.
In in vitro studies it has been shown that (R)-enantiomer of bicalutamide inhibits CYP 3A4 isoenzyme and to a lesser extent affects the activity of CYP 2C9, CYP 2C19 and CYP 2D6 isoenzymes. When bicalutamide is used for 28 days against midazolam, the area under the kinetic curve “concentration-time” (AUC) of midazolam is increased by 80%.
Inhibition of CYP 3A4 isoenzyme by bicalutamide may be important when using drugs with a narrow therapeutic index that are metabolized in the liver. In this regard, concomitant use of bicalutamide with sterfenadine, astemizole and cisapride is contraindicated.
Cautious use of bicalutamide concomitantly with cyclosporine or “slow” calcium channel blockers is necessary. Decreasing the dose of these drugs will be necessary if their effects or side effects worsen.
After initiation or withdrawal of therapy with bicalutamide, monitoring of the patient’s clinical condition and plasma concentrations of cyclosporine is recommended.
The concomitant use of bicalutamide with drugs that inhibit microsomal drug oxidation, such as cimetidine and ketoconazole, should be used with caution as there may be an increase in plasma concentration of bicalutamide, which theoretically can lead to an increase in the frequency of side effects.
Bicalutamide increases the effect of indirect coumarin-type anticoagulants, such as warfarin (competition for binding to proteins).
Special Instructions
The use in pregnancy and during breastfeeding. The drug is contraindicated in women and should not be administered to pregnant women or during breastfeeding.
Bicalutamide is actively metabolized in the liver. Given the possibility of delayed excretion of bicalutamide and its cumulation in patients with impaired liver function, liver function should be periodically evaluated (most changes in liver function occur within the first 6 months of treatment). If severe liver damage develops, bicalutamide should be discontinued.
With regard to the possibility of inhibition of CYP 3A4 isoenzyme by bicalutamide, caution should be exercised when concomitantly using with drugs predominantly metabolized with participation of CYP 3A4 isoenzyme.
When co-administered with cyclosporine, close monitoring of the patient’s condition and monitoring of plasma cyclosporine concentrations is recommended after starting use or withdrawal of bicalutamide.
When prescribing bicalutamide in patients receiving coumarin-type anticoagulants, it is recommended to monitor prothrombin time regularly.
Concomitant use with GnRH agonists may decrease glucose tolerance, which may be a manifestation of diabetes mellitus or reduced glycemic control in existing diabetes mellitus. Therefore, serum glucose concentrations should be monitored periodically.
In patients with lactose intolerance adverse reactions such as flatulence (bloating), abdominal pain, diarrhea, and rarely vomiting may occur.
Patients with lactose intolerance should be informed that each Bicane® 50 mg tablet contains 124.6 mg of lactose monohydrate; each Bicane® 150 mg tablet contains 373.8 mg of lactose monohydrate.
In patients with disease progression against the background of elevated prostate-specific antigen (PSA) concentrations, discontinuation of bicalutamide treatment should be considered.
Impact on the ability to drive vehicles, machinery. Caution should be exercised when driving vehicles and operating machinery, because some side effects of the drug, such as asthenia, headache, dizziness and sleep disorders may adversely affect the ability to perform work requiring increased concentration and rapid psychomotor reactions. If these side effects occur, you should refrain from performing the specified activities.
Contraindications
Hypersensitivity to bicalutamide or any other component of the drug. Simultaneous use of terfenadine, astemizole and cisapride. Bicalutamide is contraindicated in children and women.
Cautions:
Lactose intolerance, lactase deficiency and glucose-galactose malabsorption (because the drug contains
Lactose intolerance; liver function abnormality; concomitant use with cyclosporine or “slow” calcium channel blockers; concomitant use with drugs that inhibit microsomal oxidation of drugs (cimetidine or ketoconazole).
Side effects
Bicalutamide is well tolerated by most patients, and only in rare cases does it have to be withdrawn due to the development of side effects. Side effects reported more frequently than single observations are listed below by organ and system, with the frequency of occurrence indicated. Frequency definition: very common (â¥10%), common (â¥1% and < 10%), infrequent (â¥0.1% and < 1%), rare (â¥0.01% and < 0.1%), very rare (< 0.01%).
Hematopoietic disorders: very often – anemia*.
Endocrine system disorders: very common – gynecomastia (may persist after discontinuation of therapy, especially if the drug is taken for a long time), pain in the breasts; often – decreased libido, erectile dysfunction.
Nervous system disorders: very common – dizziness*; somnolence.
Psychiatric disorders: often, when using the drug in a daily dose of 150 mg – depression.
Chronic disorders: often – heart failure, myocardial infarction.
The risk of cardiac complications occurs when bicalutamide is used concomitantly with GnRH analogues.
Vascular system disorders: very common – “hot flashes” to the face*.
Gastrointestinal disorders: very common – nausea*, diarrhea, abdominal pain*, constipation*, decreased appetite; common – dyspepsia, flatulence.
Hepato-biliary disorders: common – hepatotoxicity, transient increase of “hepatic” transaminases activity, jaundice, cholestasis (the described changes in liver function disappear completely or decrease with continuation of therapy or after discontinuation of the drug); rarely – liver failure (fatal cases have been reported).
Metabolic and nutritional disorders: often – weight gain.
Skin and subcutaneous tissue disorders: often – skin rash, itching; when using the drug in a daily dose of 150 mg – alopecia, hair regrowth, hirsutism, dry skin.
Respiratory system, chest and mediastinum disorders: often – chest pain; infrequently – interstitial lung disease (fatal cases have been reported).
Renal and urinary tract disorders: very common – hematuria*.
Immune system disorders: infrequent – hypersensitivity reactions, including angioedema and urticaria.
General disorders: very common – asthenia, peripheral edema*.
*When taking Bicana® in a dose of 50 mg in combination with GnRH analogues side effects were observed very often.
Overdose
There have been no reported cases of overdose in humans.
Treatment:
There is no specific antidote, symptomatic therapy.
The administration of dialysis is ineffective because bicalutamide is firmly bound to plasma proteins and is not excreted unchanged by the kidneys.
General supportive therapy and monitoring of vital body functions are indicated.
Similarities
Weight | 0.032 kg |
---|---|
Manufacturer | Nativa, Russia |
Medication form | pills |
Brand | Nativa |
Related products
Buy Bicana, 150 mg 28 pcs. with delivery to USA, UK, Europe and over 120 other countries.