Ibrutinib 140 mg, containing the active ingredient Ibrutinib, is an oral Bruton's tyrosine kinase (BTK) inhibitor indicated for the treatment of various B-cell malignancies, including chronic lymphocytic leukemia (CLL), small lymphocytic lymphoma (SLL), mantle cell lymphoma (MCL), and waldenström’s macroglobulinemia (WM). It is particularly effective in patients who are relapsed or refractory to previous therapies, offering a targeted treatment option that interferes with cancer cell survival and proliferation.

Description

Ibrutinib works by irreversibly binding to BTK, an enzyme crucial for the survival and growth of malignant B cells. By inhibiting BTK, Ibrutinib disrupts the signaling pathways necessary for malignant B-cell proliferation, adhesion, migration, and survival. This leads to the reduction of tumor burden, improved control of lymphocyte counts, and prolongation of progression-free survival in patients with B-cell malignancies.

Pharmacology

Ibrutinib is a potent, selective, covalent inhibitor of BTK, a key component of the B-cell receptor (BCR) signaling pathway. BCR signaling is critical for the growth, differentiation, and survival of B cells. By inhibiting BTK, Ibrutinib interferes with downstream signaling pathways, including NF-κB and PI3K/AKT, which are involved in the survival of malignant B cells.

Ibrutinib is rapidly absorbed after oral administration and metabolized mainly by CYP3A4 in the liver. The drug has a half-life of approximately 4–6 hours, but its covalent binding to BTK allows for sustained inhibition with once-daily dosing.

Dosage & Administration

The dosage of Ibrutinib varies depending on the specific indication:

• Chronic Lymphocytic Leukemia (CLL) / Small Lymphocytic Lymphoma (SLL): Typically, 420 mg once daily.

• Mantle Cell Lymphoma (MCL): Usually 560 mg once daily.

• Waldenström’s Macroglobulinemia (WM): Standard dose is 420 mg once daily.

Ibrutinib should be taken orally with a glass of water, with or without food. Capsules should be swallowed whole and not crushed or chewed. Dose modifications may be required in cases of toxicity, drug interactions, or hepatic impairment.

Drug Interactions

Ibrutinib is metabolized by CYP3A4, and concomitant use with strong CYP3A4 inhibitors (e.g., ketoconazole, clarithromycin) may increase plasma concentrations and the risk of toxicity. Conversely, CYP3A4 inducers (e.g., rifampicin, phenytoin) may reduce drug efficacy. Caution is advised when used with anticoagulants, antiplatelet agents, or drugs affecting cardiac rhythm due to potential increased risk of bleeding or arrhythmias.

Contraindications

Ibrutinib is contraindicated in patients with known hypersensitivity to the drug or its components. Use is also cautioned in patients with severe hepatic impairment or active bleeding disorders.

Side Effects

Common side effects include diarrhea, fatigue, musculoskeletal pain, bruising, upper respiratory infections, and nausea. Less common but serious effects include bleeding events, atrial fibrillation, hypertension, infections, and cytopenias. Monitoring for cardiac events, infection, and blood counts is essential during therapy.

Pregnancy & Lactation

The safety of Ibrutinib during pregnancy and lactation has not been established. Effective contraception is recommended during treatment and for a period after discontinuation. Nursing mothers should avoid breastfeeding while taking Ibrutinib due to the potential for drug transfer into breast milk.

Precautions & Warnings

Patients should be closely monitored for bleeding, cardiac arrhythmias, infections, and cytopenias. Dose interruption or reduction may be necessary if severe adverse effects occur. Patients should also be counseled to avoid activities with a high risk of bleeding.

Therapeutic Class

Bruton's Tyrosine Kinase (BTK) Inhibitor

Storage Conditions

Store in a cool, dry place below 30°C, away from light and moisture. Keep out of reach of children.