{{short description|American biotechnology company}}
{{Infobox company | name = Gritstone Bio | former_name = Gritstone Oncology, Inc. | type = Biotechnology company | industry = Biotechnology | founded = {{Start date|2015|08}} | founder = Andrew Allen | defunct = | fate = Filed for Chapter 11 bankruptcy in October 2024 | hq_location_city = Emeryville, California | hq_location_country = U.S. | key_people = Vassiliki “Celia” Economides (interim CEO, CFO) | products = Cancer immunotherapies, infectious disease vaccines, self-amplifying mRNA SARS-CoV-2 vaccine (GRT-R910) | services = Immunotherapy and vaccine development | revenue_year = 2021 (September) | footnotes = }}
'''Gritstone bio''' was a clinical-stage American biotechnology company which attempted to develop cancer and infectious disease immunotherapies and vaccines. It was founded in August 2015 as Gritstone Oncology, Inc., with offices in Emeryville, California.
In September 2021 it raised $55.0 million from the sale of 5,000,000 shares.<ref>{{cite news |title=Gritstone Announces Private Placement Financing of $55.0 Million |url=https://www.globenewswire.com/news-release/2021/09/16/2298764/0/en/Gritstone-Announces-Private-Placement-Financing-of-55-0-Million.html |access-date=22 September 2021 |publisher=Globe Newswire |date=16 September 2021}}</ref>
It started a Phase 1 trial of its self-amplifying mRNA second generation SARS-CoV-2 vaccine, GRT-R910, in the NIHCR Manchester Clinical Research Facility at Manchester Royal Infirmary, in September 2021.<ref>{{cite news |title=Early trial of multivariant COVID-19 vaccine booster begins in Manchester |url=https://www.manchester.ac.uk/discover/news/early-trial-of-first-multivariant-covid-19-vaccine-booster-begins-in-manchester/ |access-date=22 September 2021 |publisher=ManchesterUniversity |date=20 September 2021}}</ref> This is to explore the ability of GRT-R910 to boost and expand the immunogenicity of AstraZeneca's first-generation COVID-19 vaccine AZD1222 (Vaxzevria) in healthy adults of more than 60 years. It uses lipid nanoparticles to deliver a broad set of antigens against SARS-CoV-2 that includes both stabilized spike protein and highly conserved viral protein regions containing T cell epitopes.<ref>{{cite news |title=Gritstone Bio Doses First Volunteer In Phase 1 Trial Of GRT-R910 As COVID-19 Vaccine Booster |url=https://www.nasdaq.com/articles/gritstone-bio-doses-first-volunteer-in-phase-1-trial-of-grt-r910-as-covid-19-vaccine |access-date=22 September 2021 |publisher=Nasdaq |date=20 September 2021}}</ref> Prof. Andrew Ustianowski is the study’s chief investigator.<ref>{{cite news |title=Trial of first COVID-19 variant-proof jab begins in UK |url=https://www.arabnews.com/node/1932871/world |access-date=22 September 2021 |publisher=Arab News |date=21 September 2021}}</ref>
On 10 November 2021, Gritstone announced positive preclinical data of its second-generation self-amplifying mRNA (SAM) vaccine against SARS-CoV-2 in non-human primate models.<ref>{{Cite press release |last= |first= |date=2021-11-10 |title=Gritstone Announces Positive Preclinical Data in Non-Human Primate Challenge Study with Second-Generation COVID-19 Vaccine Against SARS-CoV-2 |url=https://www.globenewswire.com/en/news-release/2021/11/10/2331315/0/en/Gritstone-Announces-Positive-Preclinical-Data-in-Non-Human-Primate-Challenge-Study-with-Second-Generation-COVID-19-Vaccine-Against-SARS-CoV-2.html |access-date=2021-12-06 |website=GlobeNewswire News Room |language=en}}</ref>
It is involved in a Phase 1/2 study, in collaboration with Bristol Myers Squibb, in 26 patients with metastatic solid tumors.<ref>{{cite news |title=Gritstone Announces Dosing of First Solid Tumor Patient with Optimized SLATE "Off-the-Shelf" Mutant KRAS-directed Neoantigen Immunotherapy in Phase 2 Clinical Trial |url=https://www.globenewswire.com/news-release/2021/09/17/2298997/0/en/Gritstone-Announces-Dosing-of-First-Solid-Tumor-Patient-with-Optimized-SLATE-Off-the-Shelf-Mutant-KRAS-directed-Neoantigen-Immunotherapy-in-Phase-2-Clinical-Trial.html |access-date=22 September 2021 |publisher=Global Newswire |date=17 September 2021}}</ref>
In October 2024, Gritstone filed for Chapter 11 bankruptcy protection in efforts to move forward with its "strategic alternatives process". The company is looking for a stalking-horse bid that would allow for the company to continue operating.<ref>{{cite web |title=Gritstone files for bankruptcy, placing future of cancer vaccine in doubt |url=https://firstwordpharma.com/story/5902758 |website=First Word Pharma |access-date=15 April 2026}}</ref>
On December 31, 2024, Andrew Allen, M.D., Ph.D., co-founder, President, and Chief Executive Officer of Gritstone Bio, stepped down from his role following the company's asset sale. Dr. Allen's departure, along with other key executives, marked a significant shift in Gritstone Bio's leadership.<ref>{{cite web |title=Gritstone Bio, Inc. Announces Resignation of Executives |url=https://www.marketscreener.com/quote/stock/GRITSTONE-BIO-INC-46372061/news/Gritstone-Bio-Inc-Announces-Resignation-of-Executives-48684056/ |website=Market screener |access-date=15 April 2026}}</ref>
== References == {{Reflist}}
== External links ==
* {{Official website|https://gritstonebio.com/about/}}
Category:Biotechnology companies of the United States Category:Companies based in California Category:COVID-19 vaccine producers Category:2015 establishments in California Category:Biotechnology companies established in 2015 Category:Companies that filed for Chapter 11 bankruptcy in 2024