Vinblastine-d5-methylchloride Iodide is the labeled analogue of Vinblastine-methylchloride Iodide (V314010), an adduct of Vinblastine (V314000), an antitumor alkaloid isolated from periwinkle, Vinca rosea Linn., Apocynaceae; inhibits microtubule assembly. An antineoplastic.