This invention relates generally to antibody-drug conjugates (ADCs). In particular, the invention relates to ADCs which comprise an antibody or antigen-binding fragment thereof which binds to prostate-specific membrane antigen (PSMA) and is conjugated to monomethylauristatin norephedrine or monomethylauristatin phenylalanine. The antibody-drug conjugate has a PC-3(TM) cell to C4-2 or LNCaP(TM) cell selectivity of at least 250. The invention also relates, in part, to compositions of and methods of using the ADCs. The methods provided include, for example, methods for treating a PSMA-mediated disease.
