show a benefit here than in, say, melanoma, where combinations of drugs like ipilimumab (Yervoy) and nivolumab are already leading to much better results.
Allen says the hope is that the first therapy—Gritstone calls them “tumor specific, neo-antigen based immunotherapies,” or TSNAs—would be ready for clinical testing by late 2016 or early 2017.
If this sounds familiar, that’s because Neon got a $55 million Series A from Third Rock Ventures and others a few weeks ago to embark on a similar task. One difference is that Gritstone is only looking at vaccine approaches, while Neon may try developing engineered T cells as a product, as well. Neon hasn’t said which cancers it’ll attack first.
Competition aside, there are a host of challenges here. For instance, Allen notes that the company’s biggest immediate goal will be to separate the signal from the noise. Which neo-antigens on a tumor cell really matter? Which ones will T cells recognize, and which are just randomly altered protein sequences? Gritstone will spend a lot of cash accumulating one lung cancer tumor sample after another, trying to uncover which ones Allen calls “magical.”
“There’s some work to be done,” he says. “But sample collection from lung cancer doctors is obviously something that we at Clovis did many times. This is our bread and butter.”
This also looks to be a complex process. Gritstone aims to biopsy a patient’s tumor, sequence it, find the relevant neo-antigens, and then make a vaccine loaded up with those key neo-antigens. Allen says the goal is to do all this work inside a month for an individual vaccine. The company will first look outside for help and likely partner with “two or three” makers of different vaccine technologies—from nucleic acid-based vaccines to peptides—to see which might work the best.
Even if Gritstone does all this work, though, there’s no guarantee patients will benefit. As of yet there is no direct evidence that creating a vaccine with neo-antigens helps cancer patients—just links that, as even Allen acknowledges, could be entirely “circumstantial.”
All of this is why the company is called Gritstone. Allen used to do a lot of rock climbing while growing up in London, sometimes scaling gritstone—a coarse type of sandstone that’s tough to ascend. Starting a new biotech company seemed like a similar challenge.
“Just before you tackle a hard climb, you sleep poorly, you’re both excited and nervous,” he says. “But then you kind of just knuckle down and tackle it.”
Aragon Pharmaceuticals and Seragon Pharmaceuticals founder Rich Heyman is on Gritstone’s board, along with Peter Svennilson (Column Group), Tom Woiwode (Versant), and Nick Simon (Clarus). In addition to Chan and Rizvi, its other scientific founders are Jean-Charles Soria of the Institut Gustave Roussy in Paris, Graham Lord of King’s College London, and Mark Cobbold of Massachusetts General Hospital.
