Eli Lilly and Co. has expanded its immuno-oncology collaboration with Merck to add a new study of Lilly’s LARTRUVO (olaratumab) with KEYTRUDA (pembrolizumab) in patients with previously treated advanced or metastatic soft tissue sarcoma (STS). Lilly will conduct the Phase I study, which is expected to begin mid-2017. Financial details were not disclosed.

The FDA recently granted accelerated approval for LARTRUVO (olaratumab injection, 10 mg/mL), in combination with doxorubicin, for the treatment of adults with STS with a histologic subtype not amenable to curative treatment with radiotherapy or surgery. LARTRUVO, in combination with doxorubicin, also recently received conditional marketing authorization from the EMA.

LARTRUVO is a platelet-derived growth factor receptor alpha (PDGFR-α) blocking antibody that specifically binds PDGFR-α and prevents receptor activation. LARTRUVO exhibits in vitro and in vivo anti-tumor activity against selected sarcoma cell lines and disrupted the PDGFR-α signaling pathway in in vivo tumor implant models.

KEYTRUDA is a humanized monoclonal antibody that works by increasing the ability of the body’s immune system to help detect and fight tumor cells. Pembrolizumab blocks the interaction between PD-1 and its ligands, PD-L1 and PD-L2, thereby activating T lymphocytes, which may affect both tumor cells and healthy cells.

“We look forward to further expanding our collaboration with Merck to include this combination study focused on advanced soft tissue sarcoma, a rare and difficult-to-treat disease with limited treatment options,” said Susan Mahony, Ph.D., senior vice president and president, Lilly Oncology. “This collaborative study builds on the exciting data we have seen with olaratumab and supports our focus on investigating the potential of combinations to enhance efficacy and change the standards of care for people with cancer.”

“Historic and present day scientific advances continue to reinforce the role of combination therapies in extending the lives of people with cancer,” said Eric Rubin, M.D., vice president and therapeutic area head, oncology early-stage development, Merck Research Laboratories. “Our collaboration with Lilly exemplifies our commitment to fully exploring combination regimens with KEYTRUDA to help arm physicians with the treatment tools they need to help their patients.”