He focused his research in viral hepatitis, pre and post-liver transplantation and most recently on metabolic-associated steatotic liver disease.

Prof. Pessoa is currently the President-Elect of the Latinamerican Association for the Study of Liver Diseases -ALEH and is also on the committee of the Global NASH Council and the Healthy Livers, Healthy Lives coalition, formed by AASLD, ALEH, APASL and EASL. He has been Principal Investigator (PI) of several multicentric trials on chronic hepatitis B and C.