Efalizumab, a novel potent regulator of T cells, is a humanized LFA-1 α subunit (CD11a) monoclonal antibody. Efalizumab has inhibitory effects on T cell activation, skin T cell transport, and T cell adhesion to keratinocytes, and can be used to study plaque psoriasis and psoriatic arthritis.

Efalizumab（78 ng/mL-5 mg/mL）在外周血中诱导白细胞增多并下调T细胞上的LFA-1表达[3]。Efalizumab（78 ng/mL-5 mg/mL）还能下调与板结合的、抗CD3刺激的PBMC增殖[3]。

Efalizumab在使用过程中可能导致包括细菌性败血症、病毒性脑膜炎、侵袭性真菌病以及由潜伏的JC病毒感染重新激活引起的进行性多灶性白质脑病(PML)等副作用[2]。