Transfer factor: A potential agent for immunotherapy of cancer

Transfer factor (TF) is an extract from human leukocytes which has been shown to transfer specific skin test reactivity to previously nonreactive human recipients, and to produce measurable increases in in Vitro tests of lymphocyte activity. The results of the experimental use of TF as an immunotherapeutic agent for cancer are reviewed. TF therapy has been associated with tumor regression, temporary stabilization or reduced need for other treatment modalities in several reported cancer patients, and may have value as an adjuvant therapy in certain malignancies. However, most of the reports involve uncontrolled studies, and no agreement exists about the definition of TF donors. Controlled studies and the use of well characterized TF donors are essential before any conclusions can be drawn about the value of TF in the therapy of cancer and other diseases.