Born in Rome, in 2015 Di Giannantonio finished as the runner-up in the Red Bull MotoGP Rookies Cup, where he had debuted the year before, and in the CIV Moto3 championship; in the same year he made his Grand Prix debut in the Moto3 World Championship with the Gresini Racing team at the Valencian Grand Prix as the replacement for the injured Andrea Locatelli, finishing the race in 23rd place.

For 2016 he was signed by the same team as a full-time rider in the same class. At the sixth race of the season, at Mugello, Di Giannantonio achieved his first championship points and his first podium finish with a second place, starting a streak of top ten finishes—including two more podiums, another second place at Assen and a third place in Brno.

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Wikipedia