GSK and Merck start Phase I trial of GSK3174998 with Keytruda

The companies have started a phase I clinical trial to evaluate GSK’s investigational GSK3174998 as monotherapy in combination with Merck’s Keytruda (pembrolizumab) in patients with tumors that have progressed after standard treatment.

GSKJ3174998 is a humanized IgG1 anti-OX40 monoclonal antibody that was discovered via collaboration with MD Anderson Cancer Center.

OX40 is a tumor necrosis factor receptor identified on the surface of activated CD4+ and CD8+ T cells.

OX40 agonism stimulates the immune system and reduces the immunosuppressive effects of regulatory T cells sometimes identified in tumors.

Keytruda is a humanized monoclonal antibody that increases the ability of the body’s immune system to fight tumor cells by blocking the interaction between PD-1 and its ligands PD-L1 and PD-L2.

It activates T lymphocytes which may affect both tumor cells and healthy cells.

Merck Research Laboratories vice president and therapeutic area head, oncology early stage development Eric Rubin said: "The initiation of this phase I trial with GSK is an important step in identifying synergistic treatment combinations that can potentially enhance the activity we are seeing with Keytruda as a monotherapy.

"We are looking forward to this trial progressing and to sharing the findings on the potential of the combination of Keytruda and GSK’s GSK3174998 in bringing forward improved outcomes for patients with advanced cancer."

Image: Keytruda increases the ability of the body’s immune system to fight tumor cells. Photo: courtesy of Copyright © 2009-2015 Merck Sharp & Dohme Corp., a subsidiary of Merck & Co., Inc.