Some experts have criticized U.S. authorities for clearing the new shots without strong data.
U.S. drug regulators on Sept. 11 cleared new COVID-19 vaccines to try to counter the poor effectiveness provided by the current options.
The U.S. Food and Drug Administration (FDA) cleared shots from Moderna and Pfizer that will be available to Americans as young as 6 months old later this month.
“Vaccination remains critical to public health and continued protection against serious consequences of COVID-19, including hospitalization and death,” Dr. Peter Marks, a top FDA official, said in a statement. “We very much encourage those who are eligible to consider getting vaccinated.”
The FDA approved the Moderna and Pfizer vaccines for people aged 12 and older. Regulators granted emergency authorization for the shots for people aged 6 months to 11 years.
There was no mention of Novavax, whose vaccine is also currently available in the United States.
The shots target XBB.1.5, a subvariant of the Omicron virus variant. That subvariant has already largely been displaced by newer strains, including EG.5, according to the U.S. Centers for Disease Control and Prevention (CDC).
The authorizations came despite a dearth of data from clinical trials.
Moderna stated that in a trial, its new shot induced immune responses against EG.5, also known as Eris, and other newer variants.
Pfizer stated that preclinical data have shown that antibodies generated by its new vaccine “effectively neutralize” EG.5.
The new shots were authorized based on studies on neutralizing antibody levels that appeared to show “a similar magnitude to the extent of neutralization observed with prior versions of the vaccines against corresponding prior variants against which they had been developed to provide protection,” the FDA stated. “This suggests that the vaccines are a good match for protecting against the currently circulating COVID-19 variants.”
The CDC plans to meet with its advisers on Sept. 12 to consider which populations it should recommend receive the new vaccines. If the panel recommends a vaccine, the federal government must pay for it.
Many countries have suggested that younger, healthy people not receive COVID-19 vaccinations as the disease has died down.
