Table 2.

Key immunotherapeutics and their primary mechanisms of action

Treatment	Mechanism(s) of action	Clinically tested agents	References
Cytokines
Interferon alpha	Activate multiple facets of immunity and has direct effects on tumor cells	Interferon alfa 2b (Intron A, Sylatron™)	[97, 98]
Interleukin-2	Activates and expands T cell	Aldeslesukin (proleukin)	[99, 100]
Vaccines
Oncolytic viral vaccines	Viral induction of tumor cell lysis and adjuvant medical host immune activation	Talimogene laherparepvec (T-VEC/Imlygic™)	[51, 101]
Peptide vaccines	Induction of tumor-specific adaptive immunity	Various tumor antigen peptides/lysates + adjuvant)	[93, 95]
Cell-based vaccines	Induction of tumor-specific adaptive immunity	Tumor cells or activated DC/APC	[102, 103]
Adoptive T cell therapy
Engineered T cells	Infusion of engineered T cells specific for tumor antigens	Transgenic TCR or CAR bearing T lymphocytes	[86, 87]
TIL	Infusion of pool anti-tumor T cells	Ex vivo expanded TIL	[85, 86]
Immune activating mAbs
αLAG-3	Blockade of T cell surface inhibitory molecule	BMS986016	[58]
αKIR	Blockade of NK cell inhibitory receptor	Lirilumab	[104, 105]
αCD137 (4-1BB)	Against of T cell costimulatory receptor	Urelumab	[106]
αPD-L1	Blockade of inhibitory checkpoint ligand expressed on immune cells and tumor cells	Atezolizumab, durvalumab, avelumab	[58, 66],
αPD-1	Blockade of inhibitory checkpoint receptor	Nivolumab (Opdivo), pembrolozumab (Keytruda),	[57, 58]
αCTLA-4	Blockade of T cell checkpoint receptor	Ipilimumab (Yervoy)	[58, 71]
	Depletion of intratumoral Treg