Last reviewed 2026-05-14 · How we verify

Astrazenica vaccine

The AstraZeneca COVID-19 vaccine (ChAdOx1 nCoV-19) uses a replication-deficient chimpanzee adenovirus vector to deliver the SARS-CoV-2 spike protein gene, triggering immune responses against the virus.

The AstraZeneca COVID-19 vaccine (ChAdOx1 nCoV-19) uses a replication-deficient chimpanzee adenovirus vector to deliver the SARS-CoV-2 spike protein gene, triggering immune responses against the virus. Used for COVID-19 prevention in adults and adolescents.

At a glance

Mechanism of action

The vaccine employs a viral vector platform where a modified adenovirus carries genetic instructions for producing the spike protein of SARS-CoV-2. Once administered, the vector enters cells and directs production of the spike protein, which the immune system recognizes as foreign and mounts both cellular and humoral immune responses. This approach generates antibodies and T-cell immunity without using the live virus itself.

Approved indications

• COVID-19 prevention in adults and adolescents

Common side effects

• Injection site pain
• Fatigue
• Headache
• Myalgia
• Fever
• Chills

Key clinical trials

• Evaluation of Clinical and Antibody Response to Covid-19 Vaccination Strategy in TBRI, Egypt (PHASE3)

Primary sources

Every claim on this page is sourced from regulatory or scientific primary sources. See our editorial policy for full methodology.

Competitive intelligence

For the full competitive landscape — auto-detected comparators, recent regulatory actions across the set, upcoming PDUFA, patent timeline, sponsor landscape:

• Astrazenica vaccine CI brief — competitive landscape report
• Astrazenica vaccine updates RSS · CI watch RSS
• Samia Hassan El-Shishtawy portfolio CI