A vaccine targeting a broad range of viruses that was designed using artificial intelligence had a “modest” effect on immune systems in a small, early trial, according to a new study.

The trial marks the first time a vaccine whose active ingredient was entirely designed by AI has been tested in humans, researchers at the University of Cambridge in the U.K. said Friday.

The experimental jab is intended to be a “universal vaccine” that protects people against a range of viruses that have previously sparked deadly outbreaks, including SARS, MERS and COVID-19.