Paclitaxel is a potent antineoplastic agent belonging to the taxane class. It is a natural diterpenoid compound originally isolated from the bark of the Pacific yew tree (Taxus brevifolia). In the Indian context, it is a cornerstone of chemotherapy for various solid tumors, widely available in both conventional and albumin-bound nanoparticle formulations. The 260mg single-dose vial is a common presentation for adult dosing regimens.
Adult: Dose varies by indication. Common regimens: Ovarian/Breast Cancer: 175 mg/m² IV over 3 hours every 3 weeks. NSCLC: 135 mg/m² IV over 24 hours followed by cisplatin, every 3 weeks. The 260mg vial is used as part of the calculated dose based on Body Surface Area (BSA).
Note: MUST be diluted in 0.9% Sodium Chloride Injection USP or 5% Dextrose Injection USP to a final concentration of 0.3 to 1.2 mg/mL. Administer via a non-PVC, polyethylene-lined administration set using an in-line filter (0.22 micron). Infuse over 3 or 24 hours as per protocol. Premedicate with dexamethasone 20 mg orally/IV 12 and 6 hours prior, diphenhydramine 50 mg IV, and ranitidine/famotidine 30-60 minutes prior to infusion.
Paclitaxel promotes the assembly of microtubules from tubulin dimers and stabilizes them by preventing depolymerization. This stabilization inhibits the normal dynamic reorganization of the microtubule network that is essential for vital interphase and mitotic cellular functions.
Pregnancy: FDA Pregnancy Category D. Paclitaxel is fetotoxic and teratogenic in animals. There is positive evidence of human fetal risk. Contraindicated in pregnancy. Women of childbearing potential must use effective contraception during and for at least 6 months after therapy.
Driving: May cause fatigue, dizziness, or peripheral neuropathy, impairing the ability to drive or operate machinery. Patients should be cautioned.
| Cisplatin | Sequence matters. Administering cisplatin BEFORE paclitaxel increases severity of myelosuppression. Paclitaxel should be given BEFORE cisplatin to minimize toxicity. | Major |
| Doxorubicin | Paclitaxel reduces the clearance of doxorubicin, increasing its AUC and risk of cardiotoxicity (congestive heart failure). Monitor cardiac function. | Major |
| Ketoconazole, Itraconazole, Clarithromycin | Strong CYP3A4 inhibitors; may decrease paclitaxel metabolism, increasing its plasma concentration and risk of toxicity. | Moderate |
| Rifampicin, Phenytoin, Carbamazepine | CYP3A4/CYP2C8 inducers; may increase paclitaxel metabolism, reducing its plasma concentration and efficacy. | Moderate |
| Live Vaccines (e.g., MMR, Varicella) | Risk of disseminated infection due to immunosuppression. Contraindicated. | Major |
Same composition (Paclitaxel (260mg)), different brands: