Pfizer is testing whether third shot will help tackle COVID-19 variants

A booster shot could be given six to 12 months after the first dose, with Pfizer testing whether it's needed to protect against future possible COVID-19 strains.

Corinne Reichert Senior Editor
Corinne Reichert (she/her) grew up in Sydney, Australia and moved to California in 2019. She holds degrees in law and communications, and currently writes news, analysis and features for CNET across the topics of electric vehicles, broadband networks, mobile devices, big tech, artificial intelligence, home technology and entertainment. In her spare time, she watches soccer games and F1 races, and goes to Disneyland as often as possible.
Expertise News, mobile, broadband, 5G, home tech, streaming services, entertainment, AI, policy, business, politics Credentials
  • I've been covering technology and mobile for 12 years, first as a telecommunications reporter and assistant editor at ZDNet in Australia, then as CNET's West Coast head of breaking news, and now in the Thought Leadership team.
Corinne Reichert
2 min read

Pfizer is testing whether a third shot is needed.

Sarah Tew/CNET

Pfizer has announced it's trialing a third COVID-19 shot to be administered six to 12 months after a patient's two-dose regimen. The trial will examine whether a booster shot of the Pfizer-BioNTech COVID-19 vaccine would tackle any new strains that emerge, the two companies said Thursday.

The study will use participants from its Phase 1 trial in the US "in order to be prepared for any potential future strain changes."

Read more: COVID-19 vaccine: Employer requirements, hidden costs, when you'll get vaccinated, more

Pfizer said it hasn't seen any evidence that its current vaccine fails to protect against new COVID-19 variants. The trial is simply to be prepared in case a strain becomes resistant to the vaccine.

"The flexibility of our proprietary mRNA vaccine platform allows us to technically develop booster vaccines within weeks, if needed," said Ugur Sahin, BioNTech CEO, in a statement. "We take these steps in order to ensure a long-term immunity against the virus and its variants."

Earlier this month, President Joe Biden announced that the US is buying enough doses of Pfizer and Moderna COVID-19 vaccines to cover 300 million people in the country by the end of July -- though this doesn't mean everyone will be vaccinated by then.

"We've now purchased enough vaccine supply to vaccinate all Americans," Biden said. Actually administering the vaccines to all Americans could take longer because vaccinations are managed at a state and local level.

Here's where to get a COVID-19 shot, and how to track how many vaccines are available in your state.

Read more: The COVID-19 vaccine is free. So how could you still get a medical bill?

The information contained in this article is for educational and informational purposes only and is not intended as health or medical advice. Always consult a physician or other qualified health provider regarding any questions you may have about a medical condition or health objectives.