Maxim Notes Progress With Maxamine Immunotherapy

Maxim Pharmaceuticals will shortly start its third Phase III trial ofMaxamine (histamine HCl), in development for treating malignant melanoma and acute myeloid leukemia. Maxamine is designed to improve the efficacy of cytokine therapies for cancer and infectious disease.

Despite initial optimism, therapy with cytokines such as interleukin-2 and interferon-alfa has been of limited use in all but a minority of cancers. Maxim believes it has identified the reason why results in other most cancers have been disappointing, and why Maxamine may greatly broaden the utility of this approach.

IL-2 and IFN-alfa recruit natural killer cells to combat tumors, but phagocytic cells such as monocytes and granulocytes also tend to be present, for antigen presentation and removal of debris. Research in Sweden has shown that phagocytes inhibit the activity of NK cells, driving them into programmed cell death via a mechanism involving the production of hydrogen peroxide (H2O2). Agonists at the histamine H2 receptor, including Maxamine, block this H2O2 release from phagocytic cells and preserve NK cell function.