Keep an eye on ALPHA at CERN. It is designed to answer this exact question by producing anti-hydrogen atoms. https://home.cern/news/news/physics/alpha-collabora

Keep an eye on ALPHA at CERN. It is designed to answer this exact question by producing anti-hydrogen atoms. https://home.cern/news/news/physics/alpha-collaboration-cern-reports-first-measurements-certain-quantum-effects https://home.cern/news/news/physics/alpha-collaboration-cern.... Their initial results a few years back were consistent with matter and antimatter acting the same under gravity, but their error bars were large enough to warrant a more precise measurement, which they're up to now.