What the WHO’s New Covid-19 Vaccine Guidance Means for Pfizer and Moderna

The guidance takes into account the diminished threat from Covid-19, and the need to commit resources to vaccinating for other diseases, the WHO’s Strategic Advisory Group of Experts on Immunization, or SAGE, said Tuesday.

“We know that we are living in an Omicron era, where the disease severity is reduced, thanks to high population-level immunity, which has been obtained either through infection or vaccine or both,” said SAGE’s chair, Dr. Hanna Nohynek.

Health authorities in the U.S. and many other countries continue to recommend a dose of a bivalent Covid-19 vaccine booster for anyone over the age of 6 months. The latest WHO guidelines represent a significant step away from that stance, and come as Covid-19 vaccine makers face pushback in the U.S. over pricing and as health officials consider a postpandemic future.

It isn’t clear how the U.S. will react to the revised WHO guidance, which isn’t binding. For now, the country is moving toward a fall 2023 Covid-19 booster campaign. The Food and Drug Administration has said it expects to hold a meeting of its vaccine advisors in June to determine which virus strain the fall boosters should target.

Nonetheless, the revised guidance points to dropping global demand for Covid-19 vaccines in coming years. Just how much demand could fall remains a vital question for leading Western Covid-19 vaccine makers Pfizer (ticker: PFE) and Moderna (MRNA).

Pfizer and Moderna both have said they expect roughly 100 million Covid-19 vaccines doses to be administered in the U.S. this year, down from 144 million in 2022.

Wall Street analysts expect Moderna’s Covid-19 vaccine sales to drop to $6.5 billion in 2024 from $18.4 billion in 2022, according to FactSet, though estimates range widely. Analysts expect Pfizer’s Covid-19 vaccine sales to drop to $12.1 billion in 2024, from $37.8 billion in 2022, also according to FactSet.

The FDA and Moderna didn’t immediately respond to a request for comment Wednesday. Pfizer, in a statement, said that Covid-19 remains a public-health threat.

“As we continue the fight against Covid-19, vaccination remains one of the best lines of defense against symptomatic disease, severe disease, and hospitalization,” a Pfizer spokesperson said. “It is, therefore, crucial for individuals to stay up-to-date on vaccination, as recommended by local health authorities.”

WHO officials also voiced skepticism over the advantages offered by the bivalent vaccines, which Moderna and Pfizer have rolled out in response to FDA requests. At a Tuesday news conference, the organization said there was “minimal evidence” showing that bivalent vaccines are more effective than monovalent vaccines, which specifically target Covid’s original strain.

“There is some additional benefit for symptomatic disease by giving the bivalent compared with the monovalent,” Dr. Kate O’Brien, director of the WHO’s department of immunization, vaccines, and biologicals, said Tuesday. “But for severe disease, we have no evidence that the bivalent product is better than the monovalent product.”

The new SAGE guidance recommends Covid-19 boosters for older adults, pregnant people, front-line health workers, younger adults with serious comorbidities like diabetes and heart disease, and people with immunocompromising conditions. People in those categories should receive boosters every six or 12 months, depending on various factors, the committee said.

SAGE said the vaccines are safe and effective for healthy children and teens up to the age of 17, but that countries should focus their efforts elsewhere, given the low burden of disease in that age group. SAGE advises vaccinating pregnant people to protect infants under the age of six months.

Write to Josh Nathan-Kazis at josh.nathan-kazis@barrons.com