Disruption of the tumor microenvironment with monoclonals directed against cell adhesion molecules and mucins has also largely been ineffective with the possible exception of anetumab ravtansine, a monoclonal antibody directed against mesothelin and conjugated with the maytansinoid DM4, an inhibitor of microtubule assembly, which is currently being assessed in a phase II trial as a part of a chemotherapeutic regimen (ClinicalTrials.gov Identifier: NCT03816358). The gene discussed is MSLN; the disease is neoplasm.