Datuk Dr. Muhammad Radzi bin Abu Hassan commenced his distinguished medical career in 1991 as a houseman at the Sultanah Bahiyah Hospital. Over the years, he progressively advanced his career, ultimately becoming a consultant physician and gastroenterologist, a role he devoted himself to from 2001 to 2022.

Currently, he holds the esteemed position of Director-General of Health within the Ministry of Health, Malaysia. Prior to assuming this prestigious role, he served as the Deputy Director-General of Health (Research and Technical Support) from 2022 to 2023. Furthermore, Datuk Radzi has held several important positions throughout his career, including the National Head of Service for Internal Medicine (2021-2022), the National Head of Service for Gastroenterology and Hepatology (2013-2020), and the Head of the Medical Department at the Sultanah Bahiyah Hospital (2004-2018). He also served as the State Physician (2005-2022), the Royal Physician (2011 to 2016), and the Head of the Clinical Research Center (2005-2022) for the Kedah State.

Apart from his clinical responsibilities and active engagement in specialist training and qualification assessment, Datuk Radzi has played a pivotal role in the formulation of national-level policies, particularly within the domain of gastroenterology and hepatology. He has been a key architect in shaping the National Strategic Plan and Clinical Practice Guidelines for hepatitis C in Malaysia. He is widely recognized as the leading figure responsible for steering the hepatitis C elimination agenda, a milestone achievement that has positioned Malaysia as a global exemplar for low-and-middle-income countries in treatment delivery. Notably, his accomplishments include the successful launch of cost-free, standardized hepatitis C treatment regimens featuring direct-acting antivirals. Additionally, he has been a driving force behind the decentralization of hepatitis C screening services and treatment, making them accessible through primary healthcare centres. Due to his extensive expertise in this field, international organizations, including the WHO, have consistently extended invitations for him to share his insights and review guidelines on viral hepatitis. Datuk Radzi's profound expertise in the field of internal medicine is exemplified by his significant contributions to research, with a particular focus on viral hepatitis, non-alcoholic fatty liver disease, and colorectal cancer. This is evident from his substantial portfolio of nearly 90 scientific publications in peer-reviewed journals, many of which were co-authored with postgraduate students co-supervised by him and research partners from renowned educational and research institutions around the world. Additionally, his collaborative efforts extend to esteemed civil society organizations, including the Drug for Neglected Diseases Initiative (DNDi), Foundation for Innovative New Diagnostics (FIND), and Médecins Sans Frontières (MSF), to advance non-industry-sponsored research initiatives. He is currently leading two ongoing trials, namely STORM-C-1 and EASE. These trials are dedicated to the development and optimization of a groundbreaking pan-genotypic direct-acting antiviral combination — comprising sofosbuvir and ravidasvir. This innovative approach has the potential to revolutionize hepatitis C treatment by offering highly affordable solutions in low-and-middle-income countries. Furthermore, Datuk Radzi led the inaugural clinical trial in Malaysia exploring the clinical benefits of Phyllanthus niruri (dukung anak), a herbal medicine, in the context of non-alcoholic fatty liver disease. His research interests cover the pursuit of novel screening methods and biomarkers for diagnosing non-alcoholic fatty liver disease and colorectal cancer. In line with his commitment to the principles of universal health coverage, Datuk Radzi is also actively engaged in research aimed at enhancing the accessibility of marginalized populations to healthcare, including individuals who inject drugs and those living in correctional settings. Following his appointment as the Director-General of Health, Datuk Radzi diligently directed his attention and efforts towards spearheading comprehensive health reform in Malaysia, guided by the Health White Paper. In addition to presiding over nearly 30 boards, councils and committees, he has primarily dedicated his time to the strategic planning and execution of initiatives aimed at the transformation of healthcare service delivery, the advancement of health promotion and disease prevention, the establishment of sustainable and equitable health financing, and the enhancement of the healthcare system's governance. He is a proponent of an open-door policy and actively advocates for public-private partnerships. His unwavering focus consistently centres on ensuring patient access to high-quality care, guided by key principles that encompass resource optimization, service decentralization and digitalization.