Despite the purported 95% effectiveness of the Pfizer-BioNTech COVID-19 vaccine, Pfizer CEO Albert Bourla announced Thursday that the vaccine maker is testing a third dose of its vaccine in anticipation of annual booster shots.

In a press release, Pfizer stated its goal was to understand the effect of a booster on immunity against COVID caused by the circulating and newly emerging SARS-CoV-2 variants and to engage in ongoing discussions with the U.S Food and Drug Administration (FDA) and European Medicines Agency regarding a clinical trial to test a modified mRNA vaccine.

Pfizer director and board member Scott Gottlieb, who also served as former FDA commissioner in charge of vaccine approval, told CNBC the vaccine maker is exploring two paths to boost effectiveness

of the COVID vaccine.

The first study will give 144 participants from the phase 1 clinical trial conducted last May a third lower-dosage of the current two-dose formulation. The second study involves testing a modified version of the existing vaccine designed to provide broad defense against a range of COVID mutations.

Pfizer hopes to prepare for a potential rapid adoption of the vaccine to address new variants that will allow for the development of booster vaccines within weeks. This “regulatory pathway” is already established for other infectious diseases like influenza, said the vaccine maker.

Pfizer’s CEO hopes a third dose will boost the immune response even higher or will offer protection against COVID variants.

“Every year, you need to go to get your flu vaccine,” Bourla said. “It’s going to be the same with COVID. In a year, you will have to go and get your annual shot for Covid to be protected,” Bourla told NBC News.

The Pfizer-BioNTech COVID vaccine is not yet licensed by the FDA but has obtained Emergency Use Authorization (EUA) to prevent COVID-19 for use in ages 16 years and older. The emergency use of this vaccine is only authorized as long as “circumstances exist justifying the authorization of emergency use.”

The FDA has said it is willing to authorize booster shots based on small clinical trials, accepting data on how well vaccines prime the immune system rather than holding out for long-term safety and efficacy results on protecting against COVID-19.

Moderna is also bolstering its worldwide manufacturing capacity in anticipation of a sustained demand for COVID-19 boosters in the coming years. The company plans to test additional doses of their vaccine, booster shots and a new shot combined with its current vaccine as soon as regulators give the green light.

As The Defender reported last week, Bill Gates is also on record suggesting a “third shot” could be required to combat COVID.