Abstract: Compounds are provided having the capability of binding therapeutically active substances to lipid containing bio-compatible particles, such as cells or viruses. These compounds include a bio-affecting moiety, comprising a therapeutically active substance, which is linked via a linking moiety to at least one hydrocarbon substituent selected so that the compounds is sufficiently non-polar to impart lipid binding capability to the compound. Thus, compounds of the invention are useful for site-selective delivery of therapeutic agents, and retention thereof at the selected site.Methods are provided for using various compounds of the invention in treatment of diseases or other pathological conditions. For example, methods are provided for treatment of: (1) post-angioplasty restenosis; (2) rheumatoid arthritis; (3) tumor cell proliferation, particularly tumor cells associated with ovarian cancer; and (4) psoriasis.