October 20, 2015
By Mark Terry, BioSpace.com Breaking News Staff
San Francisco-based Gritstone Oncology announced today that it had closed on a Series A financing round worth $102 million. Co-leading the round were Versant Ventures and The Column Group, with Clarus Ventures alongside. Additional investors included Frazier Healthcare Partners, Redmile Group, Casdin Capital, and Transformational Healthcare Opportunity.
Andrew Allen, Co-Founder, President and CEO of Gritstone Oncology
Gritstone was co-founded by Andrew Allen, who will act as president and chief executive officer. Allen co-founded Boulder, Colo.-based Clovis Oncology . Patrick Mahaffy, chief executive officer of Clovis, will act as Gritstone’s chairman.
The company will focus on cancer vaccines based on what are being called neoantigens. Allen founded the company after reading a 2014 paper in the New England Journal of Medicine that discussed why some patients don’t seem to respond to immune checkpoint inhibitors. Tumors create molecules that prevent the immune system from identifying and attacking them. So blocking those molecules allows the immune system to find and kill those tumor cells. But cancer cells are constantly mutating, creating so-called neoantigens.
“This is, to me, a massive, massive advance,” Allen told Xconomy. “[It’s a] completely rational, totally understandable, and potentially exploitable insight into how tumors can be cleared by the human immune system.”
Earlier this month, Boston-based Third Rock Ventures, along with Israel-based Clal Biotechnology Industries and New York-based Access Industries, formed Neon Therapeutics with $55 million in Series A financing. Neon is working on neoantigens as well, with a lead candidate, NEO-PV-01, which is a vaccine that will be individually programmed to respond to each patient’s unique neoantigens, and will be combined with a checkpoint inhibitor.
Gritstone’s approach will be slightly different. In newly diagnosed lung cancer patients, it will take tumor samples, sequence their DNA in order to identify specific mutations, then choose the markers that will hopefully act as the best antigens to be identified by the immune system. They will then become part of the vaccine. In other words, although Neon is looking for common neoantigens across all tumors, Gritstone plans to customize the vaccine for each individual patient.
One of the industry’s concerns over this approach is the need to essentially customized each vaccine and treatment for the patient. Although neoantigens show a great deal of promise, it’s not entirely clear how to mass produce such a vaccine and make it affordable. The technology will also need to lean on sequencing technology and bioinformatics, and face a time factor in preparing drugs for seriously ill patients.
“We’re going to learn from every patient,” Allen told Forbes. “Every product is unique to the patient.”
The nascent company indicated it believes it could acquire a tumor sample at its central laboratory, identify and evaluate the neoantigens, and customize the vaccine in approximately four weeks.
Gritstone’s other co-founders are Tim Chan and Naiyer Rizvi, both physicians at Memorial Sloan-Kettering Cancer Center. Additional co-founders include Jean-Charles Soria of the Institut Gustave Roussy in Paris, Graham Lord of King’s College London, and Mark Cobbold of Massachusetts General Hospital.
“The scientific community doesn’t yet know how to transition from individual tumor-mutation data to a short list of neoantigens that are therapeutically relevant to each patient,” said Peter Svennilson, founder and managing partner of The Column Group in a statement, “but the Gritstone team’s expertise and approach made us confident that they will be the ones to successfully tackle this scientific challenge.”
Allen and Mahaffy’s pedigree with Clovis Oncology (CLVS) is worth considering. The company has had some recent success with its drug, roceletinib, for the treatment of non-small cell lung cancer, as well as positive Phase II results from two studies in ovarian cancer for the drug rucaparib. Analysts think the company is ripe for an acquisition, often citing Gilead Sciences, Inc. and Roche as potential buyers. It’s clear they have experience in driving successful research programs, although Gritstone may present a different set of challenges.
“There’s some work to be done,” Allen told Xconomy. “But sample collection from lung cancer doctors is obviously something that we at Clovis did many times. This is our bread and butter.”
