CD4 counts should be monitored weekly during therapy with?

Alefacept is an engineered protein consisting of the CD2-binding poion of leukocyte-function-associated antigen-3 (LFA-3) fused to a human IgG1 Fc region (hinge, CH1, and CH2), approved for the treatment of plaque psoriasis. It inhibits activation of T-cells by binding to cell surface CD2, inhibiting the normal CD2/LFA-3 interaction. Treatment of patients with Alefacept also results in a dose-dependent reduction of the total number of circulating T cells, including those that predominate in psoriatic plaques. Therefore, T-cell counts of patients receiving Alefacept must be monitored, and the drug discontinued if CD4 lymphocyte levels fall below 250 cells/ L.