Vinblastine Sulfate for Injection USP is vincaleukoblastine, sulfate (1:1) (salt). It is the salt of an alkaloid extracted from Vinca rosea Linn., a common fl owering herb known as the periwinkle (more properly known as Catharanthus roseus G. Don). Previously, the generic name was vincaleukoblastine, abbreviated VLB. It is a stathmokinetic oncolytic agent. When treated in vitro with this preparation, growing cells are arrested in metaphase. Chemical and physical evidence indicates that vinblastine sulfate has the molecular formula C46H58O9N4•H2SO4 and that it is a dimeric alkaloid containing both indole and dihydroindole moieties. The structural formula is as follows:

Vinblastine sulfate is a white to off-white powder. It is freely soluble in water, soluble in methanol, and slightly soluble in ethanol. It is insoluble in benzene, ether, and naphtha.

The clinical formulation is supplied in a sterile form for intravenous use only. Vials of Vinblastine Sulfate for Injection USP contain 10 mg (0.011 mmol) of vinblastine sulfate, in the form of a white, amorphous, solid lyophilized plug, without excipients. After reconstitution with sodium chloride solution, the pH of the resulting solution lies in the range of 3.5 to 5.