The present invention provides methods and compositions for treating hyperlipidemia and/or hypercholesterolemia comprising administering to the subject an effective amount of an MTP inhibitor to inhibit hyperlipidemia and/or hypercholesterolemia in said subject, wherein said administration comprises an escalating series of doses of the MTP inhibitor. In some embodiments the method comprises administering at least three step-wise, increasing dosages of the MTP inhibitor to the subject. In some embodiments, the method further comprises the administration of one or more other lipid modifying compounds.