Antibody-drug conjugates and immunotoxins

A conjugate having the formula I:

• A-(L-D)p (I)
• or a pharmaceutically acceptable salt or solvate thereof,
• wherein:
• A is an antibody that selectively binds FAP;
• L is a linker comprising a spacer;
• D is a drug comprising a cytolysin of formula IV:
• wherein:
• R2 is H or C1-C4 alkyl;
• R6 is C1-C6 alkyl;
• R7 is C1-C6 alkyl, CH2OR19 or CH2OCOR20, wherein R19 is alkyl, R20 is C2-C6-alkenyl, phenyl, or CH2-phenyl;
• R9 is C1-C6 alkyl;
• R10 is H, OH, O-alkyl or O-acetyl;
• f is 1 or 2;
• R11 has the following structure:
• R21
• wherein
• R21 is H, OH, halogen, NH2, alkyloxy, phenyl, alkyl amino or dialkyl amino;
• R16 is H or a C1-C6-alkyl group;
• n=2, 3 or 4;
• q is 0, 1, 2 or 3;
• and
• p is 1 to 10.