Xbira — Abiraterone Acetate 250 mg (120 Tablets)

Xbira is available in the form of tablets for oral use, each containing a precise therapeutic dosage of the active substance:

• Active Compound: Abiraterone Acetate — 250 mg in each tablet.
• Excipients: Lactose monohydrate, microcrystalline cellulose, croscarmellose sodium (guaranteeing proper and stable disintegration of the tablet in the gastrointestinal tract), magnesium stearate, colloidal silicon dioxide, and sodium lauryl sulfate.
• Appearance: Oval, biconvex tablets, white to off-white in color, supplied in a dense protective plastic bottle with an original cap.

Pharmacodynamics: Abiraterone acetate is rapidly hydrolyzed in the body to an active metabolite — abiraterone, which acts as a potent inhibitor of the 17α-hydroxylase/17,20-lyase (CYP17) enzyme. This enzyme is critically required for androgenesis. The blockade of the enzyme leads to a drop in serum testosterone levels to undetectable values, halting the proliferation of cancer cells.

Pharmacokinetics: After oral administration, the drug reaches peak plasma concentration within 2 hours. Taking the tablets simultaneously with fatty or any other food causes a massive, avalanche-like increase in systemic exposure to abiraterone (up to 10-fold), which can trigger dangerous systemic toxicity. The medication must be taken strictly on an empty stomach.

Xbira 250 mg is prescribed by a qualified oncologist for combination treatment in conjunction with low doses of glucocorticosteroids (prednisolone) for:

• 🔹 Metastatic Castration-Resistant Prostate Cancer (mCRPC): In patients whose disease continues to progress despite androgen deprivation therapy, as well as after the use of docetaxel-based chemotherapy regimens.
• 🔹 High-Risk Metastatic Hormone-Sensitive Prostate Cancer (mHSPC): As a first-line therapy in combination with standard androgen deprivation therapy to prevent the spread of metastatic foci.

Strict compliance with the prescribed dosage regimen and time intervals is a key success factor in anti-tumor therapy:

• Standard Dose: The recommended daily dosage is 1000 mg, which corresponds to exactly 4 tablets of 250 mg each, taken together once a day.
• Administration Rules: Tablets must be taken strictly on an empty stomach. No food should be consumed for at least 1 hour before taking the drug and for 1 hour after its consumption.
• Mandatory Condition: Treatment with Xbira must be accompanied by the daily intake of low-dose prednisolone (as prescribed by the doctor) to compensate for adrenal suppression.
• Method of Use: Tablets must be swallowed whole, accompanied by a sufficient volume of clean water. It is prohibited to chew, crush, or break the tablets before intake.

Prescribing the drug is excluded or strictly limited in the presence of the following clinical factors:

• ⛔ Hepatic Impairment: The drug is contraindicated in patients with severe hepatic impairment (Child-Pugh Class C).
• ⛔ Gender and Age: The drug is developed exclusively for the treatment of men. It is categorically contraindicated in women of any age and children under 18 years.
• ⛔ Pregnancy: Absolute contraindication due to the extremely high risk of teratogenic effects on the fetus.
• ⛔ Cardiac Pathologies: Severe heart failure, recent myocardial infarction, or dangerous forms of arrhythmia require discontinuation or careful weighing of risks.
• ⛔ Hypersensitivity: Presence of allergic reactions to abiraterone or any other excipient of the medication.

Abiraterone actively affects the metabolism of many medicines in the liver, requiring constant compatibility monitoring:

• ❌ CYP3A4 Inhibitors and Inducers: Strong inducers (such as rifampicin, phenytoin, carbamazepine, or St. John's wort-based products) can significantly reduce the therapeutic concentration of Xbira, making the treatment ineffective.
• ❌ CYP2D6 Substrates: Abiraterone increases the concentration of drugs metabolized by this enzyme (such as metoprolol, dextromethorphan, haloperidol), increasing the risk of their toxicity.
• ⚠️ Special Attention: Concurrent prescription of medicines capable of prolonging the QT interval on an ECG requires regular cardiac monitoring.

Even though Xbira is intended for men, compliance with reproductive safety rules is of vital importance:

• Measures for Patients: The active substance can pass into semen. If your partner is pregnant, the use of a condom is strictly mandatory throughout the entire course of treatment and for 1 week after its completion.
• Measures for Partners: If the partner is of childbearing potential, two reliable methods of contraception (including a barrier method) must be used during therapy.
• For Others: Pregnant women or women planning pregnancy are categorically forbidden to handle damaged or broken tablets without protective gloves, as the substance is easily absorbed through the skin and can cause fetal development defects.

Due to its mechanism of action, the drug can cause side effects, most of which are successfully managed by the concurrent intake of prednisolone:

• 🟢 Very Common: Edema of the lower extremities (fluid retention), decreased serum potassium levels (hypokalemia), increased blood pressure (hypertension).
• 🟡 Gastrointestinal: Diarrhea, dyspepsia, nausea, vomiting.
• 🟡 Infections and Laboratory: Urinary tract infections, reversible increase in liver transaminase levels (ALT/AST) in blood plasma.
• 🟠 Rare But Serious: Heart failure, heart rhythm disorders, hepatotoxicity.
• ⚠️ Urgent Doctor Consultation: It is required to contact a doctor immediately if severe muscle pain, pronounced shortness of breath, or yellowing of the sclera of the eyes or skin occurs.

Cases of acute clinical overdose with the drug are limited, but exceeding the dose increases systemic risks:

• Possible Symptoms: Sharp drop in potassium levels, critical rise in blood pressure, arrhythmia, and increased toxic effects on the liver.
• First Aid: Immediate discontinuation of the drug, gastric lavage, and intake of activated charcoal.
• Treatment: No specific antidote exists. Symptomatic and supportive therapy is carried out in a hospital setting with mandatory monitoring of cardiac and hepatic functions.

Proper storage of the medication guarantees the preservation of its full therapeutic activity:

• 🌡️ Temperature Regimen: Store in a dry place at a stable temperature between 15°C and 30°C. Avoid excessive overheating and exposure to moisture.
• 📦 Packaging: Keep the tablets in the original, tightly closed plastic bottle to protect them from environmental exposure and light.
• 👶 Safety: Store in a hidden and secure place that is absolutely inaccessible to children and pets.
• ⏳ Package Contents: The original sealed bottle contains 120 tablets, which is completely designed for a standard 30-day therapeutic course (when taking 4 tablets per day).