Clinical Trials & Research News

3 Doses of Pfizer’s COVID-19 Vaccine Neutralizes Omicron Variant

In other COVID news, Medicago’s COVID-19 vaccine was 71% effective in a Phase 3 trial and Europe extends Roche’s Actemra authorization to include the treatment of COVID-19.

COVID-19 Vaccine

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By Samantha McGrail

- Pfizer and BioNTech recently announced that their COVID-19 vaccine neutralized the SARS-CoV-2 Omicron variant after three doses.

A month after receiving the booster vaccination, sera obtained from the vaccine neutralized the Omicron variant to levels comparable to those observed for the wild-type SARS-CoV-2 spike protein after two doses.

Additionally, sera from individuals who received two doses of the vaccine exhibited an over 25-fold reduction in neutralization titers against the Omicron variant compared to wild-type.

And a third dose provided a similar level of neutralizing antibodies to Omicron as is observed after two doses against wild-type and other variants that emerged before Omicron, a Pfizer spokesperson explained.

These antibody levels are associated with high efficacy against both the wild-type virus and these variants. 

“Although two doses of the vaccine may still offer protection against severe disease caused by the Omicron strain, it’s clear from these preliminary data that protection is improved with a third dose of our vaccine,” Albert Bourla, chairman and CEO of Pfizer, said in the announcement.

“Ensuring as many people as possible are fully vaccinated with the first two-dose series and a booster remains the best course of action to prevent the spread of COVID-19,” Bourla continued.

Pfizer and BioNTech will continue to collect more laboratory data and evaluate real-world effectiveness to assess and confirm protection against Omicron and inform the most effective path forward.

And based on their experience with COVID-19 vaccines, the companies are confident that they can deliver an Omicron-based vaccine in March 2022 if needed.

Medicago’s COVID-19 Vaccine 71% Effective in Phase 3 Trial 

Medicago recently announced that its COVID-19 vaccine, combined with GSK’s pandemic adjuvant, was safe and effective in a global Phase 3 clinical trial.

The trial enrolled over 24,000 individuals 18 years of age and older across six countries. The overall vaccine efficacy rate against all variants of SARS-CoV-2 was 71 percent. And for individuals with initial seronegative status, vaccine efficacy was 75.6 percent.

Additionally, Medicago’s vaccine was 75.3 percent effective against COVID-19 of any severity for the Delta variant and 88.6 percent against the Gamma variant.

Researchers observed no cases of the Alpha, Lambda, or Mu variants in the vaccinated group but noted 12 cases in the placebo group. Notably, the Omicron variant was not circulating during the study.

Based on trial results, Medicago will seek regulatory approval from Health Canada as part of its rolling submission.

“The global COVID-19 pandemic is continuing to show new facets with the current dominance of the Delta variant, upcoming Omicron, and other variants likely to follow,” Thomas Breuer, global COVID-19 adjuvanted vaccines lead and chief global officer at GSK, said in the announcement.

“The combination of GSK’s established pandemic adjuvant with Medicago’s plant-based vaccine technology has significant potential to be an effective, refrigerator-stable option to help protect people against SARS-CoV-2,” Breuer continued.

Europe Extends Roche’s Actemra Authorization to Include COVID-19 Treatment

The European Commission recently extended the marketing authorization for Roche’s Actemra to include the treatment of COVID-19 in adults who are receiving systemic corticosteroids and require mechanical ventilation.

This decision comes at the heels of the recommendation from the European Medicines Agency (EMA) Committee for Medicinal Products for Human Use (CHMP), which shows the urgent need for Actemra as a potential treatment option during the COVID-19 pandemic.

“Actemra is the second Roche medicine to have received rapid European Commission approval in COVID-19 in recent weeks,” Levi Garraway, MD, PhD, chief medical officer and head of global product development, said in the announcement.

“Together with vaccines, other treatments and testing, Actemra/RoActemra forms an important piece of the care puzzle as we confront new challenges of the pandemic in Europe and around the world,” Garraway continued.

The European Commission’s decision follows results from four studies of Actemra in 5,500 patients with severe or critical COVID-19, including the Roche-led COVACTA, EMPACTA, and REMDACTA trials and the University of Oxford’s RECOVERY study, supported by Roche.

Actemra was previously approved in Australia, authorized for emergency use in the US and Ghana, and recommended by the World Health Organization (WHO) to treat COVID-19.