Correlations of clinical and laboratory effects of treatment with levamisole in autoimmune disease.

Studies in which levamisole has been used with success in the treatment of rheumatoid arthritis and other autoimmune diseases may provide information useful in cancer treatment with regard to optimal dosage regimens and methods for monitoring laboratory effects. Using the response of peripheral blood lymphocytes to phytohemagglutinin mitogen measured by the uptake of tritiated thymidine in 3-day culture, patients with rheumatoid arthritis were found to have a significantly deficient response compared to normal subjects. Levamisole treatment reversed this deficiency and normalized lymphocyte mitogen responses. These studies showed the benefit of a dose of 150 mg of levamisole compared to lower doses and also showed equal maintenance of immunocompetency with a dose of 150 mg/week compared to daily levamisole. In addition, compared to poor clinical responders, good clinical responders were shown to have a greater enhancement in mitogen response, both during the treatment period and when levamisole was added in vitro to lymphocyte culture prior to drug treatment. It was concluded that laboratory studies of lymphocyte mitogen response may contribute towards better management of patients receiving levamisole therapy.