IL-2 injections boost CD4 cells

Self-administered injections of immune system protease interleukin-2 (IL-2) can dramatically increase CD4 counts, but more study is needed to see if the improvements can be sustained.

Investigators at the National Institutes of Health report that half of 18 patients in the trial sustained CD4 cells increases of at least 200 cells after one year. The researchers note that intermittent cycles of subcutaneous IL-22 therapy can be self-administered safely.

"This new study demonstrates that subcutaneous IL-2, used in combination with protease inhibitors and other antiretroviral drugs, has the potential to enhance the therapeutic effects conferred by antiretroviral treatments alone," says Richard Davey, MD, senior investigator at the National Institute of Allergy and Infectious Diseases.

The trial, which began in 1993, enrolled patients with CD4 counts greater than 200 and allowed them to continue antiretroviral therapy. In an extended follow-up, eight patients have remained on IL-2 therapy for more than three years. Five have sustained CD4 counts of 800 to 2,000 cells by self-injecting daily doses every two to four months.