The rate of release of encapsulated active compound from a multivesicular liposomal (MVL) formulation is modified by selection of a neutral lipid component. A family of MVL formulations containing different slow:fast release neutral lipid molar ratios display different release rates depending upon the molar ratio of the fast release neutral lipid to the slow release neutral lipid in each member. Incubation in plasma or a plasma-like medium at in vivo temperatures so as to obtain a release rate curve for each allows selection from among the members of the family of a liposomal formulation with a desired rate of release in vivo.