Product Information
Registration Status: ActiveCYTAX PACLITAXEL INJECTION USP CONCENTRATE 6MG/ML is approved to be sold in Singapore with effective from 2019-02-20. It is marketed by ACCORD HEALTHCARE PTE LTD, with the registration number of SIN15632P.
This product contains Paclitaxel 6 mg/ ml in the form of INJECTION, SOLUTION, CONCENTRATE. It is approved for INTRAVENOUS use.
This product is manufactured by INTAS PHARMACEUTICALS LIMITED in INDIA.
It is a Prescription Only Medicine that can only be obtained from a doctor or a dentist, or a pharmacist with a prescription from a Singapore-registered doctor or dentist.
Description
Paclitaxel is a mitotic inhibitor used in cancer chemotherapy. It was discovered in a US National Cancer Institute program at the Research Triangle Institute in 1967 when Monroe E. Wall and Mansukh C. Wani isolated it from the bark of the Pacific yew tree, Taxus brevifolia and named it taxol. Later it was discovered that endophytic fungi in the bark synthesize paclitaxel. When it was developed commercially by Bristol-Myers Squibb (BMS), the generic name was changed to paclitaxel and the BMS compound is sold under the trademark Taxol. In this formulation, paclitaxel is dissolved in Kolliphor EL and ethanol, as a delivery agent. A newer formulation, in which paclitaxel is bound to albumin, is sold under the trademark Abraxane.
Indication
Used in the treatment of Kaposi's sarcoma and cancer of the lung, ovarian, and breast. Abraxane® is specfically indicated for the treatment of metastatic breast cancer and locally advanced or metastatic non-small cell lung cancer.
Mechanism of Action
Paclitaxel interferes with the normal function of microtubule growth. Whereas drugs like colchicine cause the depolymerization of microtubules in vivo, paclitaxel arrests their function by having the opposite effect; it hyper-stabilizes their structure. This destroys the cell's ability to use its cytoskeleton in a flexible manner. Specifically, paclitaxel binds to the β subunit of tubulin. Tubulin is the "building block" of mictotubules, and the binding of paclitaxel locks these building blocks in place. The resulting microtubule/paclitaxel complex does not have the ability to disassemble. This adversely affects cell function because the shortening and lengthening of microtubules (termed dynamic instability) is necessary for their function as a transportation highway for the cell. Chromosomes, for example, rely upon this property of microtubules during mitosis. Further research has indicated that paclitaxel induces programmed cell death (apoptosis) in cancer cells by binding to an apoptosis stopping protein called Bcl-2 (B-cell leukemia 2) and thus arresting its function.
Pharmacokinetics
- Absorption
- When a 24 hour infusion of 135 mg/m^2 is given to ovarian cancer patients, the maximum plasma concentration (Cmax) is 195 ng/mL, while the AUC is 6300 ng•h/mL.
- Distribution
- * 227 to 688 L/m^2 [apparent volume of distribution at steady-state, 24 hour infusion]
- Metabolism
- Hepatic. In vitro studies with human liver microsomes and tissue slices showed that paclitaxel was metabolized primarily to 6a-hydrox-ypaclitaxel by the cytochrome P450 isozyme CYP2C8; and to two minor metabolites, 3’-p-hydroxypaclitaxel and 6a, 3’-p-dihydroxypaclitaxel, by CYP3A4.
- Elimination
Clearance
* 21.7 L/h/m2 [Dose 135 mg/m2, infusion duration 24 h] * 23.8 L/h/m2 [Dose 175 mg/m2, infusion duration 24 h] * 7 L/h/m2 [Dose 135 mg/m2, infusion duration 3 h] * 12.2 L/h/m2 [Dose 175 mg/m2, infusion duration 3 h]
Toxicity
Rat (ipr) LD50=32530 µg/kg. Symptoms of overdose include bone marrow suppression, peripheral neurotoxicity, and mucositis. Overdoses in pediatric patients may be associated with acute ethanol toxicity.
Active Ingredient/Synonyms
(2AR-(2aalpha,4beta,4abeta,6beta,9alpha(alpha r*,betas*),11alpha,12alpha,12balpha))-beta-(benzoylamino)-alpha-hydroxybenzenepropanoic acid 6,12b-bis(acetyloxy)-12-(benzoyloxy)-2a,3,4,4a,5,6,9,10,11,12,12a,12b-dodecahydro-4,11-dihydroxy-4a,8,13,13-tetramethyl-5-oxo-7,11-methano-1H-cyclodeca(3,4)benz(1,2-b)oxet-9-yl ester | 5beta,20-Epoxy-1,2-alpha,4,7beta,10beta,13alpha-hexahydroxytax-11-en-9-one 4,10-diacetate 2-benzoate 13-ester with (2R,3S)-N-benzoyl-3-phenylisoserine | Paclitaxel | Taxol A | Paclitaxel |
Source of information: Drugbank (External Link). Last updated on: 3rd July 18. *Trade Name used in the content below may not be the same as the HSA-registered product.