WASHINGTON, Sep 7 (Reuters) - Pfizer said on Monday it had dosed the first patient in a trial testing a flu vaccine based on messenger RNA, the same technology used in the COVID-19 shots made by the US drugmaker and BioNTech.

The early-stage trial, conducted in the United States, will test the vaccine in healthy adults ages 65- 85.

"The COVID-19 pandemic allowed us to deliver on the immense scientific opportunity of mRNA. Influenza remains an area where we see a need for vaccines," said Kathrin Jansen, head of vaccine research and development at Pfizer.

The study will test the safety and immune responses of the vaccine, compared to another FDA-approved influenza vaccine.