Gaithersburg, Maryland-based pharmaceutical company Novavax, which has not yet applied for regulatory approval for its COVID-19 vaccine, will begin testing the new vaccine in combination with its influenza vaccine.

The phase one and two human trials will be conducted in Australia and will enroll 640 healthy adults between 50 to 70 who have either previously been infected with COVID-19 or who are fully vaccinated with approved COVID-19 vaccines. The human trials will be conducted at up to 12 sites, with results expected during the first half of 2022, Novavax said.

The trials will evaluate safety, tolerability and immune response. Participants will receive two doses of the combination vaccine, the second 56 days after the first.

Novavax said in preclinical studies the combination vaccine demonstrated robust immune responses to both influenza and COVID-19.

“The combination of these two vaccines, which have individually delivered outstanding results with favorable safety and tolerability profiles, may lead to greater efficiencies for the healthcare system and achieve high levels of protection against COVID-19 and influenza with a single regimen,” said Dr. Gregory M. Glenn, president of research and development at Novavax.

Novavax is expected to apply for regulatory approval of its COVID-19 vaccine in the coming months.

In large, late-stage human trials in the U.S. and Mexico, Novavax’s two-shot COVID-19 vaccine was 90% effective overall, and demonstrated 100% protection against moderate and severe disease.