Patent ID: 8617558

Claim:
A method for delivering a camptothecin drug, comprising administering to a subject a composition comprising a conjugate of a camptothecin drug and a targeting moiety of the formula: TM-[L3]-[L2]-[L1] m AA n -CPT, where TM is a targeting moiety selected from the group consisting of a murine, chimeric, primatized, humanized, and human monoclonal antibody (MAb), and said antibody is an intact antibody, an antibody fragment selected from the group consisting of Fab, Fabâ€², F(ab)2 and F(abâ€²)2, or a single-chain construct antibody sub-fragment; CPT is camptothecin or an analog thereof; L3 is a component of a cross-linker comprising an antibody-coupling moiety; L2 comprises a defined PEG (polyethylene glycol) with 1-12 monomeric units attached to L3 at one end with a triazole moiety, is attached to L1 at the other end by an amide, hydrazide, carbonate or ester bond, or to CPT by a carbonate bond when L1 and AA are absent, or attached to AA by an amide bond when L1 is absent; L1 comprises a collapsible linker, or a peptidase-cleavable moiety optionally attached to a collapsible linker, or an acid-cleavable moiety; AA is an amino acid; m is an integer with values of 0 or 1, and n is an integer with values of 0, 1, 2, 3, or 4; and when n is >1, the amino acids represented by AA can be the same or different.