Study of Pralatrexate & Gemcitabine With B12 & Folic Acid to Treat Relapsed/Refractory Lymphoproliferative Malignancies

This study is for patients with lymphoproliferative malignancies that have progressed after receiving a previous treatment (relapsed) or are no longer responding to treatment (refractory). To be in this study, patients must have certain types of Hodgkin’s lymphoma (HL), peripheral T-cell lymphoma (PTCL), or B-cell lymphoma, including Waldenstrom’s macroglobulinemia.
This study is being done to find doses of the combination of pralatrexate and gemcitabine with vitamin B12 and folic acid that can be safely given to patients with these types of lymphoma and explore the effectiveness of the treatment.