COVID-19 Vaccine AZD1222 Moves to US Phase 3 Trial

AstraZeneca’s investigational coronavirus disease 2019 (COVID-19) vaccine candidate, AZD1222, has expanded into a phase 3 clinical trial, according to a press release.¹

The US trial, called D8110C00001, is funded by the Biomedical Advanced Development Authority (BARDA) and the National Institute of Allergy and Infectious Diseases (NIAID). The NIAID-supported COVID-19 Prevention Network will participate in the trial.

The trial is enrolling up to 30,000 adults aged 18 years or older to assess the safety, efficacy, and immunogenicity of AZD1222, previously known as ChAdOx1 nCoV-19, for the prevention of COVID-19, AstraZeneca said. Participants will include those who are healthy or have stable underlying medical conditions, including those living with HIV, and who are at increased risk of infection.

AZD1222, which was co-invented by the University of Oxford and Vaccitech, uses a replication-deficient chimpanzee viral vector based on a weakened version of a common cold virus that causes infections in chimpanzees and contains the genetic material of a severe acute respiratory disease coronavirus 2 (SARS-CoV-2) virus spike protein.

The study will randomize individuals to receive 2 doses of either the vaccine candidate or a saline control, 4 weeks apart, with twice as many participants receiving the potential vaccine than the control. Late-stage trials of AZD1222 are ongoing in the United Kingdom, Brazil, and South Africa, with trials anticipated to start in Japan and Russia. Combined with the US clinical trial, up to 50,000 participants globally will be included.

Interim results from the ongoing phase 1/2 COV001 trial showed AZD1222 was well tolerated and generated robust immune responses against SARS-CoV-2 in all participants. The trial incorporated 1077 healthy adult participants between the ages of 18 and 55 years old and evaluated a single dose of AZD1222 against a comparator meningococcal conjugate vaccine. In addition to the single dose, 10 adults also received 2 doses of AZD1222 1 month apart.²

In the early trial data, the vaccine prompted effective immune and T cell responses, resulting in a 4-fold increase in antibodies for SARS-CoV-2 in 95% of participants 1 month following receipt of the vaccine. All participants showed a T cell response that remained 2 months after being administered AZD1222. The study findings were published in The Lancet.²

“We are pleased that AZD1222 demonstrated safety and immunogenicity across all adult age groups and are proud to be collaborating with BARDA and NIAID to accelerate the development of this vaccine,” Mene Panagalos, executive vice president of BioPharmaceuticals R&D, said in a statement.¹ “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.”

References

1. Development of COVID-19 vaccine AZD1222 expands into US Phase III clinical trial across all adult age groups. News Release. AstraZeneca; August 31, 2020. Accessed September 2, 2020. https://www.astrazeneca.com/content/astraz/media-centre/press-releases/2020/development-of-covid-19-vaccine-azd1222-expands-into-us-phase-iii-clinical-trial-across-all-adult-age-groups.html#!

2. The Lancet: UK’s vaccine against SARS-CoV-2 is safe and induces an immune reaction. News Release. EurekAlert; July 20, 2020. Accessed July 20, 2020. https://www.eurekalert.org/pub_releases/2020-07/tl-tlu072020.ph