Two pharmaceutical giants, Pfizer and Moderna, have this week started clinical trials for a Covid-19 vaccine specifically designed to target the Omicron variant.
Moderna announced yesterday that the first participant received the Omicron-specific booster candidate as part of a Phase 2 study.
Earlier this week, Pfizer revealed that 1 420 participants between the ages of 18 and 55 were enrolled in the company’s clinical trial.
Both vaccine types use messenger RNA (mRNA) technology. This type of vaccine uses a genetically engineered molecule to give your cells instructions on how to fight the Covid-19 virus.
A South African study found that while the Omicron variant may cause less severe illness than earlier variants, it could be more resistant to the two-dose Pfizer-BioNTech vaccine.
CEO and co-founder of BioNTech, Professor Ugur Sahin, said their study aims to help develop a variant-based vaccine that achieves a similar level of protection against Omicron as it did with earlier variants.
“Vaccines continue to offer strong protection against severe disease caused by Omicron. Yet, emerging data indicate vaccine-induced protection against infection and mild to moderate disease wanes more rapidly than was observed with prior strains,” he said.
Pfizer plans to test the immune response generated by the Omicron-specific vaccine both as a three-shot regimen in unvaccinated people and as a booster shot for people who already received two doses of their original vaccine.
Moderna’s Phase 2 study of Omicron-specific booster candidates will examine two groups of 300 people each. One group includes participants who received the two-dose primary series of the vaccine and another that includes participants who received two shots and a booster dose.
Moderna said results from a previous small laboratory study found that protection from the Omicron variant with its booster dose is likely to fade over six months.
CEO of Moderna, Stéphane Bancel, said the company is evaluating whether to include this Omicron-specific candidate in their multivalent booster programme.
"We are reassured by the antibody persistence against Omicron at six months after the currently authorised 50 µg booster of mRNA-1273. Nonetheless, given the long-term threat demonstrated by Omicron’s immune escape, we are advancing our Omicron-specific variant vaccine booster candidate," he said.
ANNOUNCEMENT 📢: Given the long-term threat demonstrated by Omicron’s immune escape, we are pleased to announce that the first participant has been dosed in the Phase 2 study of our #Omicron-specific #booster candidate (mRNA-1273.529)! Learn more: https://t.co/wtbRLWEBh9 pic.twitter.com/vpFV9ORA7i— Moderna (@moderna_tx) January 26, 2022