The research on virotherapy under the leadership of the Rigvir inventor Dr. Aina Muceniece began in 1960 at the Latvian Academy of Sciences Institute of Microbiology. Already in the first pre-clinical studies it was found that viruses isolated from the gastrointestinal tract of healthy children are oncolytic. In order to optimize the development of cancer virotherapy the first Cancer Virotherapy laboratory in the world headed by Dr.Muceniece was established in 1965 in the Institute of Microbiology.
Extensive preclinical studies were started to screen the effect and adapt the most potent of the selected viruses. Dr. Muceniece always remembered the first finding: “Surprisingly, to one of the viruses the tumour really reacted – it disappeared. Without a trace, as if it had never existed. In fascination, I placed the little hamster in the sun to see with my own eyes that the growth indeed has disappeared. It was an extremely powerful moment of inspiration. Ever since, the belief has been rooted in me that the study of cancer virotherapy has to be continued”. The first clinical studies were started in 1968 of what today is known as the Riga virus, Rigvir.