Neuroimmunotherapy with low-dose subcutaneous interleukin-2 plus melatonin in AIDS patients with CD4 cell number below 200/mm3: a biological phase-II study

A phase-II pilot clinical study was performed to evaluate the effects of low-dose subcutaneous IL-2 with the pineal hormone melatonin (MLT) in AIDS patients with CD4 counts below 200/mm3. The study included 11 patients. IL-2 was given subcutaneously at 3 million IU/ day in the evening for 6 days/week for 3 weeks. MLT was given orally at 40 mg/day in the evening every day, starting 7 days prior to IL-2. The treatment was substantially well tolerated, and in particular no cardiovascular or pulmonary complication occurred. An increase in CD4 cell number greater than 30% occurred in 4/11 (36%) patients, and CD4 cell mean values observed during the study were significantly higher with respect to those found before. In addition, the treatment induced a significant increase in mean number of lymphocytes, eosinophils, T lymphocytes, NK cells, CD25- and DR-positive lymphocytes. Finally, CD4/CD8 mean ratio significantly increased during the study. This preliminary clinical study suggests that the combined neuroimmunotherapy with low-dose subcutaneous IL-2 and MLT may improve the immune status also in AIDS patients with CD4 cell counts below 200/mm3, who generally do not respond to IL-2 alone.