The methods and compositions described herein address the need in the art by providing compositions and methods for a therapy with an antibody that is specifically targeted to and/or retained intra- or peri-tumorally, limiting systemic exposure and reducing side-effects. Accordingly, aspects of the disclosure relate to a composition comprising an immunotherapeutic antibody operatively linked to an extracellular matrix (ECM)-affinity peptide. An ECM-affinity peptide is one that has affinity for an extracellular matrix protein.