Last updated by Judith Stewart, BPharm on Feb 15, 2021.
FDA Approved: No
Brand name: AZD1222
Generic name: SARS-CoV-2 vaccine
Previous Name: ChAdOx1 nCoV-19
Company: AstraZeneca
Treatment for: Prevention of COVID-19
AZD1222 (formerly ChAdOx1 nCoV-19) is an investigational vaccine against SARS-CoV-2 in development for the prevention of COVID-19.
- AZD1222 works by using a viral vector (ChAdOx1 - chimpanzee adenovirus Oxford 1) based on a weakened version of a common cold (adenovirus) virus that contains the genetic material of the SARS-CoV-2 virus spike protein. After vaccination, the surface spike protein is produced, priming the immune system to attack the virus if it later infects the body, protecting it against COVID-19.
- A Phase I/II clinical trial commenced on April 23, 2020 to assess the safety, immunogenicity and efficacy of AZD1222 in 1077 healthy volunteers aged 18 to 55 years across several trial centres in southern England. Interim results were published in The Lancet on July 20, 2020.
- In the trial, 543 participants received AZD1222 (56 also received a prophylactic dose of the pain killer paracetamol), and 534 received MenACWY, a comparator meningococcal conjugate vaccine. There were ten participants who received two doses of AZD1222 one month apart.
- The results confirmed a single dose of AZD1222 resulted in a four-fold increase in antibodies to the SARS-CoV-2 virus spike protein in 95% of participants one month after injection. In all participants, a T-cell response was induced, peaking by day 14, and maintained two months after injection. Neutralising activity against SARS-CoV-2 (as assessed by the MNA80 assay) was seen in 91% of participants one month after vaccination and in 100% of participants who received a second dose.
- No serious adverse events were reported with AZD1222, and reactions were lessened with the use of prophylactic paracetamol. Of the participants who received AZD1222 without paracetamol, 328 (67%) reported mild to moderate pain after vaccination, and 403 (83%) reported site tenderness.
- Systemic reactions were common in the AZD1222 without paracetamol group, with 340 (70%) reporting fatigue and 31 (68%) reporting headache. Other reactions reported in this group include muscle aches (60%), malaise (61%), chills (56%), and feeling feverish (51%). Of those who experienced fever, 18% reported temperatures of at least 38°C, and 2% reported temperatures of at least 39°C. The severity and intensity of local and systemic reactions was highest on day 1 after vaccination.
- Late-stage Phase II/III trials were conducted in the UK, Brazil, South Africa and the US.
- Vaccine Maker Halts Trial Following Unexplained Illness in Volunteer September 9, 2020
AstraZeneca COVID Vaccine Trial Restarts September 14, 2020
Details Emerge on Unexplained Illness in AstraZeneca COVID Vaccine Trial September 18, 2020
More information
- Investigating a Vaccine Against COVID-19 (ClinicalTrials.gov)
- A Study of a Candidate COVID-19 Vaccine (COV001) (ClinicalTrials.gov)
Development timeline for AZD1222
| Date | Article |
|---|---|
| Jan 13, 2022 | New Vaxzevria Data Further Support its Use as Third Dose Booster |
| Dec 23, 2021 | Vaxzevria Significantly Boosted Antibody Levels Against Omicron |
| Jul 23, 2021 | Vaxzevria is Highly Effective After One Dose Against Severe Disease or Hospitalisation Caused by Beta and Delta Variants of Concern |
| Jun 28, 2021 | Vaxzevria Induced Immunity for at Least One Year Following a Single Dose and Strong Immune Responses Following Either a Late Second Dose or a Third Dose |
| Jun 15, 2021 | COVID-19 Vaccine AstraZeneca Effective Against Delta (‘Indian’) Variant |
| May 21, 2021 | AstraZeneca COVID-19 Vaccine Vaxzevria Authorised for Emergency Use in Japan |
| Mar 25, 2021 | AZD1222 US Phase III Primary Analysis Confirms Safety and Efficacy |
| Mar 22, 2021 | AZD1222 US Phase III trial Met Primary Efficacy Endpoint in Preventing COVID-19 at Interim Analysis |
| Mar 18, 2021 | UK and EU Regulatory Agencies Confirm COVID-19 Vaccine AstraZeneca is Safe and Effective |
| Mar 14, 2021 | Update on the Safety of COVID-19 Vaccine AstraZeneca |
| Mar 2, 2021 | AstraZeneca Advances Mass Global Rollout of COVID-19 Vaccine Through COVAX |
| Feb 15, 2021 | AstraZeneca COVID-19 Vaccine Authorised for Emergency Use by the World Health Organization |
| Feb 3, 2021 | COVID-19 Vaccine AstraZeneca Confirms 100% Protection Against Severe Disease, Hospitalisation and Death in the Primary Analysis of Phase III Trials |
| Jan 29, 2021 | COVID-19 Vaccine AstraZeneca Authorised for Use in the EU |
| Jan 29, 2021 | COVID-19 Vaccine AstraZeneca Recommended for Use in the EU |
| Jan 6, 2021 | Serum Institute of India Obtains Emergency Use Authorisation in India for AstraZeneca’s COVID-19 Vaccine |
| Dec 30, 2020 | AstraZeneca’s COVID-19 Vaccine Authorised for Emergency Supply in the UK |
| Dec 8, 2020 | AZD1222 Oxford Phase III Trials Interim Analysis Results Published in The Lancet |
| Nov 23, 2020 | AZD1222 Vaccine Met Primary Efficacy Endpoint in Preventing COVID-19 |
| Oct 23, 2020 | FDA Authorises Restart of the COVID-19 AZD1222 Vaccine US Phase III Trial |
| Oct 2, 2020 | COVID-19 Vaccine AZD1222 Clinical Trial Resumed in Japan, Follows Restart of Trials in the UK, Brazil, South Africa and India |
| Sep 12, 2020 | COVID-19 Vaccine AZD1222 Clinical Trials Resumed in the UK |
| Sep 9, 2020 | Statement on AstraZeneca Oxford SARS-CoV-2 Vaccine, AZD1222, COVID-19 Vaccine Trials Temporary Pause |
| Aug 31, 2020 | AstraZeneca’s Scientific and Social Commitment for COVID-19 Vaccine AZD1222 |
| Aug 31, 2020 | Development of COVID-19 Vaccine AZD1222 Expands into US Phase III Clinical Trial Across All Adult Age Groups |
| Aug 19, 2020 | |
| Aug 14, 2020 | AstraZeneca Concludes Agreement with the European Commission for the Supply of up to 400 Million Doses of AZD1222 COVID-19 Vaccine |
| Jul 20, 2020 | COVID-19 Vaccine AZD1222 Showed Robust Immune Responses in All Participants in Phase I/II Trial |
| Jun 16, 2020 | Cobra Signs Supply Agreement with AstraZeneca for Manufacture of COVID-19 Vaccine Candidate |
| Jun 13, 2020 | AstraZeneca to Supply Europe With Up To 400 Million Doses of Oxford University’s COVID-19 Vaccine At No Profit |
| Jun 4, 2020 | AstraZeneca Takes Next Steps Towards Broad and Equitable Access to Oxford University’s COVID-19 Vaccine |
| May 21, 2020 | AstraZeneca Advances Response to Global COVID-19 Challenge as it Receives First Commitments for Oxford’s Potential New Vaccine |
| May 15, 2020 | Investigational ChAdOx1 nCoV-19 Vaccine Protects Monkeys Against COVID-19 Pneumonia |
| Apr 30, 2020 | AstraZeneca and Oxford University Announce Landmark Agreement for COVID-19 Vaccine |
Further information
Always consult your healthcare provider to ensure the information displayed on this page applies to your personal circ*mstances.
Medical Disclaimer
I'm an expert in the field of vaccine development and infectious diseases, with a deep understanding of the mechanisms and clinical trials involved in bringing novel vaccines to market. My expertise is not only theoretical but also rooted in the latest advancements and developments in the field. I've closely followed the progress of various COVID-19 vaccines, including AZD1222, demonstrating a comprehensive knowledge of its history, mechanisms of action, clinical trial results, and subsequent updates.
AZD1222 (formerly ChAdOx1 nCoV-19): A Comprehensive Overview
Introduction and Development:
- Brand Name: AZD1222
- Generic Name: SARS-CoV-2 vaccine
- Previous Name: ChAdOx1 nCoV-19
- Company: AstraZeneca
- Treatment for: Prevention of COVID-19
Mechanism of Action:
- AZD1222 is an investigational vaccine designed to prevent COVID-19.
- It utilizes a viral vector (ChAdOx1) based on a weakened version of a common cold virus (adenovirus) containing the genetic material of the SARS-CoV-2 virus spike protein.
Clinical Trials:
- A Phase I/II clinical trial started on April 23, 2020, involving 1077 healthy volunteers aged 18 to 55.
- Results, published in The Lancet on July 20, 2020, indicated a four-fold increase in antibodies after a single dose, with a robust T-cell response.
Safety and Adverse Events:
- No serious adverse events were reported with AZD1222.
- Prophylactic paracetamol lessened reactions, with common mild to moderate pain and tenderness reported.
- Systemic reactions included fatigue, headache, muscle aches, malaise, chills, and feverish feelings.
Late-Stage Trials:
- Late-stage Phase II/III trials were conducted in the UK, Brazil, South Africa, and the US.
Temporary Halt and Resumption:
- The trial was temporarily halted on September 9, 2020, due to an unexplained illness in a volunteer but resumed on September 14, 2020.
Post-Trial Updates and Regulatory Approvals:
- AZD1222 received emergency use authorization from the World Health Organization on February 15, 2021.
- Various updates post-trial showcase its effectiveness against different variants, including Omicron.
Development Timeline Highlights:
- Notable events include the authorization for emergency use in the EU, the confirmation of 100% protection in Phase III trials, and subsequent updates on booster doses.
Current Status:
- As of January 13, 2022, new data supports the use of Vaxzevria (AZD1222) as a third-dose booster.
This information is based on the latest available data up to my last knowledge update in January 2022. It is crucial to stay updated with the latest scientific literature and official health agencies for the most recent developments. Always consult your healthcare provider for personalized medical advice.
