LTX-315 (trifluoroacetate salt)

LTX-315 is a synthetic cationic amphiphilic peptide.¹ It is cytotoxic to a variety of human cancer cell lines, including A20 lymphoma and AT-84 squamous cell carcinoma cells (IC₅₀s = 8.3 and 11 µM, respectively), and to non-cancerous MRC-5 fibroblasts (IC₅₀ = 34.3 µM) but not human red blood cells (EC₅₀ = >695 µM).² LTX-315 is also cytotoxic to drug-sensitive and -resistant cancer cell lines (IC₅₀s = 2.1-6.4 and 2.5-3.2 µM, respectively). It permeabilizes mitochondrial membranes and induces immunogenic cell death in tumor cells in vitro.^3,1 Intratumoral administration of LTX-315 (1 mg peptide/50 µl saline) increases tumor levels of IL-1β and IL-6 and induces necrosis in, and complete regression of, tumors in a B16/F1 syngeneic mouse model of melanoma.⁴

1.Zhou, H., Forveille, S., Sauvat, A., et al.The oncolytic peptide LTX-315 triggers immunogenic cell deathCell Death Dis.7(3)e2134(2016) 2.Huag, B.E., Camilo, K.A., Eliassen, L.T., et al.Discovery of a 9-mer cationic peptide (LTX-315) as a potential first in class oncolytic peptideJ. Med. Chem.59(7)2918-2927(2016) 3.Zhou, H., Forveille, S., Sauvat, A., et al.The oncolytic peptide LTX-315 kills cancer cells through Bax/Bak-regulated mitochondrial membrane permeabilizationOncotarget6(29)26599-26614(2015) 4.Camilo, K.A., Berge, G., Ravuri, C.S., et al.Complete regression and systemic protective immune responses obtained in B16 melanomas after treatment with LTX-315Cancer Immunol. Immunother.63(6)601-613(2014)