On the heels of Pfizer's announcement that its vaccine will soon receive full approval from the Food and Drug Administration (FDA), pharmaceutical company Moderna is informing the public that new studies show its COVID-19 vaccines are 93% effective for six months after a person receives a second dose.

The Cambridge-based company made the announcement Thursday, with CEO Stéphane Bancel saying, “We are pleased that our COVID-19 vaccine is showing durable efficacy of 93% through six months, but recognize that the Delta variant is a significant new threat so we must remain vigilant.”

The announcement is based on discoveries made during the company’s Phase 3 study of the vaccine, which involved data collected before the Delta variant appeared in the United States.

The company added that a booster "will likely be necessary prior to the winter season."

The company anticipates developing a single-dose annual booster that provides protection against COVID-19, flu and RSV in adults.

Moderna said Phase 2 study of the vaccine in children ages 6 months to 11 years is still a work-in-progress.