Use of Levamisole in Cancer Patients

Summary

Levamisole is a synthetic, orally active immunomodifier. Although it does not generally influence normal immune reactivity, it is capable of restoring to normal levels depressed immune reactions. Levamisole acts as a thymomimetic agent stimulating the functional activities of depressed T-lymphocytes and phagocytes, and promoting their maturation-differentiation. Its biochemical mode of action involves intracellular cyclic nucleotides, but is only partially resolved.

As the drug does not directly affect cancer cells, it is not a remission-inducing agent and its use as monotherapy in cancer is not recommended. On the other hand, when levamisole was used as an adjunct to conventional antineoplastic therapies in different cancer types, a degree of therapeutic activity (e.g. increased survival, lower recurrence rates, longer remission duration) has been observed in a majority of clinical randomised and nonrandomised trials. Clinical experience is still limited, but an appropriate body weight or surface-adjusted dose, early treatment after completion of primary treatment and neoplasm responsiveness to primary therapy appear to be important determinants of therapeutic effectiveness with levamisole, which should be given intermittently avoiding concomitant administration with cytotoxic treatments. Levamisole is well tolerated in the majority of patients, side effects being primarily allergicidiosyncratic, neurological and gastrointestinal, with agranulocytosis potentially the most severe.