TABLE 2.

Phase 1 Trial Characteristics and Classes of the Investigated Agents

Characteristic	Trials (n = 150), No. (%)
Trials by year
1995-1999	49 (33)
2000-2004	38 (25)
2005-2009	29 (19)
2010-2015	35 (23)
Investigated agents
Targeted therapy
DNA damage repair pathway	29 (19)
Epigenetic modification	13 (9)
Cell cycle checkpoint regulators	10 (7)
VEGF/VEGFR inhibition	9 (6)
BRAF-MEK-ERK pathway	7 (5)
NF-κB signaling pathway	6 (4)
Notch signaling pathway	6 (4)
PI3K/AKT/mTOR pathway	4 (3)
Apoptosis pathway	4 (3)
Hormone receptor pathway	3 (2)
Protein kinase C pathway	3 (2)
EGFR inhibition	2 (1)
Hedgehog signaling pathway	1 (1)
Cytotoxic
Microtubules	13 (9)
Topoisomerase inhibitors	10 (7)
Alkylating agents	6 (4)
Antimetabolites	2 (1)
HIF-1α	2 (1)
Platinum	1 (1)
Retinoid	1 (1)
Immunotherapy
Vaccine therapy	8 (5)
Interleukin	3 (2)
PD-1	1 (1)
IDO1 inhibitor	1 (1)
Other
Miscellaneous agents	5 (3)