Johnson & Johnson's Single-Dose COVID Vaccine Is 66% Effective on 'Moderate to Severe Illness'

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Johnson & Johnson is sharing new data related to its potential COVID-19 vaccine.

The company issued a press release Friday offering new details from a phase 3 study that involved 43,783 participants with 468 symptomatic coronavirus cases. Johnson & Johnson touted their option's availability at one dose compared to other options that require two shots, like Moderna and Pfizer vaccines that are already being rolled out.

Johnson & Johnson noted, however, that their results showed a lower rate of efficacy in certain areas: it's 66% effective overall in preventing moderate to severe COVID 28 days after vaccination. Additionally, it is 85% effective overall against severe COVID illness.

By contrast, two-dose Moderna and Pfizer vaccines have proven to be about 95% effective. Though, Johnson & Johnson said their results are "promising."

"These topline results with a single-shot COVID-19 vaccine candidate represent a promising moment," said Paul Stoffels, vice chairman of the executive committee and chief scientific officer at Johnson & Johnson. "The potential to significantly reduce the burden of severe disease, by providing an effective and well-tolerated vaccine with just one immunization is a critical component of the global public health response."

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"A one-shot vaccine is considered by the World Health Organization to be the best option in pandemic settings, enhancing access, distribution and compliance," he continued. "Eighty-five percent efficacy in preventing severe COVID-19 disease and prevention of COVID-19-related medical interventions will potentially protect hundreds of millions of people from serious and fatal outcomes of COVID-19. It also offers the hope of helping ease the huge burden placed on healthcare systems and communities."

Alex Gorsky, chairman of the board of directors and CEO of Johnson & Johnson, said the company's goal has been to "create a simple, effective solution for the largest number of people possible, and to have maximum impact to help end the pandemic."

"We're proud to have reached this critical milestone and our commitment to address this global health crisis continues with urgency for everyone, everywhere," added Gorsky.

In addition to the latest Johnson and Johnson vaccine, the recent Novavax vaccine is said to be 89% effective at preventing the illness following the Phase 3 clinical trial in U.K.

The Novavax is different from Pfizer and Moderna as it is a protein subunit vaccine, according to the CDC. But like the other two brands, the Novavax vaccine is given in two doses spaced 21 days apart.

And while the vaccine appears to be effective against preventing the original COVID strain, it is slightly less effective against the new virus variant in South Africa, according to a Novavax press release.

As of Friday morning, Jan. 29, at least 21,698,606 people in the U.S. have received at least one dose of either Pfizer's or Moderna's COVID-19 vaccine, according to the CDC. Only 4,263,056 people have gotten both doses.

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