AstraZeneca’s COVID-19 Vaccine Candidate Enters 30,000-Person Phase III Trial

AstraZeneca’s COVID-19 Vaccine Candidate Enters 30,000-Person Phase III Trial
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On Tuesday, AstraZeneca the launch of a 30,000-patient Phase III trial in the U.S. of AZD1222, the COVID-19 vaccine it is co-developing with the University of Oxford and a spinout—a study that will account for most of the 50,000 participants on which the company intends to assess the vaccine.

The Phase III D8110C00001 trial (NCT04516746) is intended to evaluate the safety, efficacy, and immunogenicity of AZD1222 (formerly ChadOx1 nCoV-19) for the prevention of COVID-19. Participants will be randomized to receive two doses of either AZD1222 or a saline control, four weeks apart, with twice as many participants receiving the potential vaccine than the saline control.

Local and systemic reactions and immune responses will be assessed in 3,000 of the participants, AstraZeneca added.

“Should clinical trials demonstrate the vaccine protects against COVID-19 disease and is approved for use, we will work hard to make it globally available in a fair and equitable manner as rapidly as possible,” Mene Pangalos, AstraZeneca’s executive vice president, BioPharmaceuticals R&D, promised in a statement.

According to, the Phase III trial will be conducted at 62 study centers. Those centers, AstraZeneca said, are recruiting up to 30,000 adults aged 18 years and older from diverse racial, ethnic and geographic groups who are healthy or have stable underlying medical conditions, including those living with HIV, and who are at increased risk of infection from SARS-CoV-2. Centers outside the US were included based on predicted transmission rates of the virus, with sites in Peru and Chile expected to begin recruitment “shortly,” the company said.

AstraZeneca said it has late-stage clinical trials ongoing in the UK, Brazil, and South Africa, with additional trials set to start in Japan and Russia. In all, the trials will enroll 50,000 participants

Results from the late-stage trials are anticipated later this year, depending on the rate of infection within the clinical trial communities, AstraZeneca said.

AZD1222 is based on an adenovirus vaccine vector and the COVID-19 spike protein. After vaccination, the surface spike protein of the coronavirus is produced, which primes the immune system to attack the coronavirus if it later infects the body.

Core values

Just yesterday, AstraZeneca declared its “commitment to the highest safety standards and to broad and equitable access” worldwide for AZD1222—and articulated two core values it said will govern its development of the vaccine: “Follow the science” and “put patients first.”

AstraZeneca also restated that it has increased its production capacity for AZD1222 toward 3 billion doses of the vaccine, citing supply announcements covering Russia, South Korea, Japan, China, Latin America, and Brazil.

AZD1222 has been developed by the University of Oxford’s Jenner Institute, whose researchers in April partnered with colleagues from the University’s Oxford Vaccine Group to begin clinical development of the vaccine by launching the COV001 Phase I/II trial (NCT04324606).

Researchers from AstraZeneca, the University of Oxford, and partners on July 20 published positive preliminary data from COV001 showing AZD1222 to have an acceptable safety profile, and favorable immunogenicity against the virus. Among the 543 participants randomized to AZD1222, a single dose resulted in a four-fold increase in antibodies to the SARS-CoV-2 virus spike protein in 95% of participants at Day 28 after injection, the researchers reported. In all participants, a T-cell response was induced, peaking by day 14, and maintained two months after injection.

“The preliminary results of this first-in-human clinical trial supported clinical development progression into ongoing phase 2 and 3 trials,” the researchers concluded in their study, published in The Lancet.

In April, AstraZeneca said it would oversee global development, manufacturing, and distribution of the vaccine, establishing a partnership with the University of Oxford designed to enable rapid production and distribution of the vaccine should it prove effective in clinical studies. AstraZeneca has also inked a license agreement with the University and its spinout company Vaccitech, which has joint rights to the platform technology behind AZD1222.

BARDA, NIAID funding

AstraZeneca is leading the trial, which is being funded by the Biomedical Advanced Development Authority (BARDA), and the NIH’s National Institute of Allergy and Infectious Diseases (NIAID).

BARDA has committed up to $1.2 billion toward development, production, and delivery of AZD1222 via Operation Warp Speed, the program through which President Donald Trump’s administration has committed the nation to delivering 300 million vaccine doses protecting against SARS-CoV-2 by January 2021.

In addition to the U.S. Phase III trial, BARDA also agreed to fund another trial designed to evaluate the vaccine in children. AstraZeneca has agreed to furnish BARDA with 300 million doses of the vaccine.

Also participating in the Phase III trial will be the NIAID-supported COVID-19 Prevention Network (CoVPN), a clinical trials network formed in July with the aim of enrolling thousands of volunteers in large-scale clinical trials for COVID-19 vaccines and monoclonal antibodies.

Through Warp Speed, CoVPN merged four existing NIAID-funded clinical trials networks focused on other diseases: the HIV Vaccine Trials Network (HVTN), based in Seattle; the HIV Prevention Trials Network (HPTN), based in Durham, N.C.; the Infectious Diseases Clinical Research Consortium (IDCRC), based in Atlanta; and the AIDS Clinical Trials Group, based in Los Angeles.