. Author manuscript; available in PMC: 2016 May 4.

Published in final edited form as: Nat Rev Cancer. 2012 Mar 22;12(4):252–264. doi: 10.1038/nrc3239

Table 1.

The clinical development of agents that target immune-checkpoint pathways

Target	Biological function	Antibody or Ig fusion protein	State of clinical development ^*
CTLA4	Inhibitory receptor	Ipilimumab	FDA approved for melanoma, Phase II and Phase III trials ongoing for multiple cancers
CTLA4	Inhibitory receptor	Tremelimumab	Previously tested in a Phase III trial of patients with melanoma; not currently active
PD1	Inhibitory receptor	MDX-1106 (also known as BMS-936558)	Phase I/II trials in patients with melanoma and renal and lung cancers
		MK3475	Phase I trial in multiple cancers
		CT-011^‡	Phase I trial in multiple cancers
		AMP-224^§	Phase I trial in multiple cancers
PDL1	Ligand for PD1	MDX-1105	Phase I trial in multiple cancers
PDL1	Ligand for PD1	Multiple mAbs	Phase I trials planned for 2012
LAG3	Inhibitory receptor	IMP321^∥	Phase III trial in breast cancer
LAG3	Inhibitory receptor	Multiple mAbs	Preclinical development
B7-H3	Inhibitory ligand	MGA271	hase I trial in multiple cancers
B7-H4	Inhibitory ligand		Preclinical development
TIM3	Inhibitory receptor		Preclinical development

CTLA4, cytotoxic T-lymphocyte-associated antigen 4; FDA, US Food and Drug Administration; Ig, immunoglobulin; LAG3, lymphocyte activation gene 3; mAbs, monoclonal antibodies; PD1, programmed cell death protein 1; PDL, PD1 ligand; TIM3, T cell membrane protein 3.

As of January 2012.

^‡

PD1 specificity not validated in any published material.

^§

PDL2–Ig fusion protein.

^∥

LAG3–Ig fusion protein.