Bay Area's Aduro Biotech Throws in the Towel on CRS-207, Will Wind Down Trials
CRS-207 was a first-generation attenuated strain of Listeria that was engineered to express the antigen mesothelin, which is associated with tumors. It was being evaluated as a way to jumpstart the immune system to attack tumors in mesothelioma and ovarian and gastric cancers.
“We would like to thank the patients, their families, our clinical investigators and staff for their time and commitment to these trials, which will contribute important data to the field of oncology,” said Stephen Isaacs, chairman and chief executive officer of Aduro, in a statement. “While we are disappointed with the results for CRS-207, our clinical development program was designed to quickly generate data that could inform timely decision-making and allow us to prioritize our portfolio accordingly. We will shift our focus and investment toward our STING agonist program, B-select antibodies and personalized neoantigen approach with pLADD.”
On Nov. 10, Aduro announced promising preclinical studies with ADU-1604, the company’s humanized anti-CTLA-4 monoclonal antibody. Data culled from both in vitro and in vivo experiments showed the potency of the compound and that it was able to inhibit tumor growth and stimulate T cell-dependent antibody response.
The data was presented at the 32nd Annual Meeting of the Society for Immunotherapy of Cancer (SITC) in November. The drug has potential for several different cancer types as a monotherapy or as part of a combination therapy.
“These data from preclinical studies of ADU-1604, a novel anti-CTLA-4 product candidate derived from our proprietary B-select antibody platform, are encouraging and provide support to file an Investigational New Drug Application to advance ADU-1604 into clinical studies,” Andrea van Elsas, Aduro’s chief scientific officer, stated. “As a company with multiple programs and proprietary technology platforms, we are well positioned to leverage our product candidates, as monotherapies and in rational combinations, to develop new treatment options for patients in need.”
CTLA-4 stands for cytotoxic T-lymphocyte-associated protein 4. It is a negative regulator of T-cells and is an immune checkpoint. Blocking CTLA-4 has the potential to produce an anti-tumor response by stimulating T cell activation, as well as by improving the T cells’ cancer killing activity. The target has been clinically validated by others in advanced melanoma.
The company believes that ADU-1604, when combined with immune cell stimulators, such as STING agonists and cancer vaccines, shows an amplified anti-tumor effect against certain tumors.
In today’s announcement, Isaacs added, “In our STING program in particular, there are several additional clinical trials under consideration to complement our ongoing Phase I dose escalation trial of ADU-S100 as well as our combination study with Novartis’ PD-1 checkpoint inhibitor, PDR-001. As a result of our portfolio decisions, we expect our current cash balance to be sufficient to fund planned activities for the next three years through 2020.”