Atreca bags $125M as solid tumor trial comes into view

Atreca has raised $125 million to step up its R&D activities. The series C round comes as Atreca gears up to move its lead solid tumor drug into the clinic and boost the throughput of the industrialized discovery engine it has built up over the past seven years. 

California’s Atreca established its credentials over the past few years through VC rounds that added $91 million to its coffers and attracted the support of investors including GlaxoSmithKline and the Bill & Melinda Gates Foundation. GSK and the Gates Foundation began working with Atreca, too, as did leading pharma companies including Johnson & Johnson, Novartis, Pfizer and Sanofi.

Atreca attracted the attention on the strength of its novel approach to drug discovery, which probes the B-cell responses to identify novel antibodies and the targets that engage with them.

“The ability to discover novel antibody-target pairs turns the traditional drug discovery process on its head,” Atreca CEO John Orwin said. “Instead of starting with a target and then companies rushing into figure out the best way to drug that target, we start with the responding patients and what the immune system revealed to us.”

Orwin, the former SVP of oncology at Genentech, joined Atreca in April after leading Relypsa to a $1.5 billion takeover by Vifor Pharma. The appointment returned Orwin to the oncology space and put him in charge of guiding Atreca through the next stage of its evolution. 

ATRC-101 is spearheading the evolution of Atreca. Orwin and his colleagues are yet to disclose the target of the antibody, saying only that it works to treat solid tumors through driver antigen engagement. More details will emerge as Atreca advances the drug, which is expected to enter the clinic by the end of next year.

Atreca is progressing earlier-stage candidates with different mechanisms, too, and is planning to keep its pipeline stocked by expanding its capabilities and raising the number of animal models in which it tests its antibodies.

So far, Atreca’s cranking of its discovery engine has uncovered more than 1,000 antibodies. Some of these, such as ATRC-101, have direct effector functions, making them suitable for use as therapeutic monoclonal antibodies. Others bind specifically to tumors but have little to no effect on cancer cells. Atreca wants to partner these antibodies.  

“One of the other priorities is partnering some of those antibodies with emerging technologies like bispecifics, like antibody drug conjugates, potentially in the CAR-T space, T-cell engagers. Essentially, we've created the content with these novel antibody-target pairs that we think paired with the right technologies could create a lot of value,” Orwin said. 

Deal-making activity in recent months suggests that proposition could resonate with companies that own novel modalities. Bluebird bio, for example, teamed up with with Gritstone and Regeneron last month to access novel targets and antibody targeting vehicles to use with its cell therapy platform.

The series C round was led by the still-anonymous “large U.S.-based, healthcare-focused fund” that has bankrolled Atreca’s rise. Fellow existing backers Wellington Management and Cormorant Asset Management contributed, too, as did new investors Aisling Capital, Boxer Capital of the Tavistock Group, EcoR1 Capital, Redmile Group, Samsara BioCapital and Tekla Capital Management.