Novel agents in indolent lymphomas.

Indolent non-Hodgkin's lymphomas (iNHLs) include follicular lymphomas (FL), marginal-zone lymphoma, lymphoplasmacytic lymphoma/Waldenström macroglobulinemia and small lymphocytic lymphoma. First-line standard therapy in advanced, symptomatic iNHL consists of rituximab-based immunochemotherapy. The recent rediscovery of the 'old' chemotherapeutic agent bendamustine, an alkylating agent with a peculiar mechanism of action, has added a new effective and well-tolerated option to the therapeutic armamentarium in iNHL, increasing response rates and duration. However, patients invariably relapse and subsequent active and well-tolerated agents are needed. In recent years a large number of new targeted agents have been tested in preclinical and clinical experimentation in FL and indolent nonfollicular lymphoma (iNFL), including the new monoclonal antibodies binding CD20 or other surface antigens, immunoconjugates and bispecific antibodies. Moreover novel agents directed against intracellular processes such as proteasome inhibitors, mTOR inhibitors and agents that target the tumour microenvironment, notably the immunomodulatory agent lenalidomide, are under active clinical investigation. The development of these new drugs may change in the near future the approach to iNHL patients, leading to better tolerated and effective therapy regimens.