The FDA Says Third Dose Of COVID-19 Vaccine Not Necessary Despite Boosting Immunity

Vaksin PfizerBioNTech (Wikimedia Commons/U.S. Secretary of Defense)

JAKARTA - United States Food and Drug Administration (FDA) scientists say booster doses or a third dose of Pfizer's COVID-19 vaccine may not be necessary, even though the third injection produces a higher immune response or immunity in recipients.

The FDA staff member said in a document prepared as an entry, it remains unproven if the efficacy of Comirnaty, the COVID-19 vaccine Pfizer developed with Germany's BioNTech SE, is declining.

"Some observational studies have suggested decreased efficacy of Comirnaty over time against symptomatic infection or against the Delta variant, while others have not", they said in the document, cited from Reuters, Thursday, September 16.

"However, overall, the data suggest that currently a COVID-19 vaccine licensed or authorized by the United States, still provides protection against severe COVID-19 illness and death in the United States", the document continued.

The FDA staff said the booster dose met a pre-determined condition that regulators had set to show the shot produced an immune response.

However, they said licensing documents for boosters must also take into account the ability to prevent hospitalizations and deaths, as well as the dynamics of the pandemic in the United States.

The agency released the document Wednesday for consideration by a committee of outside experts who will meet on Friday to decide whether to recommend whether US regulators should approve a third dose or a booster dose.

The views of FDA staff reflect that many scientists question whether boosters are widely needed, even as President Joe Biden has pushed for additional injections in the face of a spike in hospitalizations and deaths caused by the highly contagious Delta variant of the coronavirus.

President Biden set a September 20 target to start administering 100 million boost-dose vaccines in the United States.

After the FDA meets, a U.S. Centers for Disease Control and Prevention (CDC) advisory panel plans to meet next week to make recommendations, according to White House Press Secretary Jen Psaki.

Pfizer, in a document prepared for the meeting, argues US regulators should approve a booster shot of its vaccine, for use six months after the second dose because its effectiveness diminishes over time.

Pfizer says data from its own clinical trials show the vaccine's efficacy decreases by about 6 every two months after the second dose. It also noted that the incidence of breakthrough COVID-19 cases in the trial was higher among people who received the injection earlier.

The company also points to real-world data from Israel and the United States showing a decrease in the effectiveness of Pfizer/BioNTech vaccines.

While in a clinical trial of about 300 participants, the third dose produced a better immune response than the second. It also points to data from a booster program that was recently started in Israel which showed a third dose restored a high level of protection from the virus.

Some US officials hope the boosters can prevent mild cases and reduce transmission of the virus, as well as reduce COVID-19 hospitalizations and deaths, which could speed America's recovery.