"A pioneer in antiviral research, Dr. Erik De Clercq (1941) began his medical career in 1966, received his certification in Clinical Pathology in 1971, and his Ph.D. the following year. While at the Rega Institute for Medical Research, he led teams that discovered some of the first anti-HIV medications and played a central role in developing the paradigm-shifting concept of combination therapy for HIV, which today is the most effective treatment strategy for HIV/AIDS patients. Over his prodigious career, Dr. De Clercq’s research focused on the development of new therapies, and in particular, the development of new agents against viral infections. He is widely recognized for his seminal work in the field of nucleotide analogs, which were the first broad-spectrum antivirals, and sparked a new era in antiviral development."


Quote from the Dr. Paul Janssen Award for Medical Research press release (2010)

Prof. De Clercq headed the Rega Foundation (from 1985 till 2011) and combined this function with the chairmanship of the Department of Microbiology and Immunology (from 1986 to 1991, and again from 1999 to 2004). 

His proudest achievement next to the discovery of Tenofovir was the development of a treatment for herpes zoster (Shingles) that is still widely used. Together with his team, he led the way to a stem cell mobilizer, a revolution in cancer treatments. He is just as proud of the approval by the FDA of Tanovea, a drug to cure lymphoma cancer in dogs.

Email address:



Rega Institute for Medical Research

Herestraat 49 - box 1030

3000 Leuven



+32 16 379020

Erik De Clercq and Antonin Holy

Antonin Holy and Erik De Clercq became co-inventors of a key class of antiviral drugs a.o. Tenofovir to combat the HIV virus