Virotherapy – How it works?

RigVir – pioneer of oncolytic virotherapy

RigVir is the first oncolytic virotherapy medicine worldwide. It is a native, genetically non-modified, non-pathogenic, melanoma cell-adapted RNA virus of Picornaviridae family, Enterovirus genus, human orphan type 7 (ECHO7) virus. RigVir is provided as a frozen solution for injection in 2 ml vials and should be transported and kept frozen (-20 ± 2°C) until injection.

Affecting only cancer cells

The direct anti-tumor effect of RigVir is due to its oncotropic and oncolytic properties. RigVir infects only cancer cells while leaving normal cells unaffected and do not cause severe illness or side effects. RigVir is suitable for repeated treatments.

RigVir promotes expression of tumor-associated differentiation antigen and inhibits the expression of MAGE group antigens that are associated with progressive growth of melanoma on the surface of non-destroyed cancer cells.

Stimulating the immune system

RigVir stimulates humoral immunity – B cell activation, production of antibodies and interferon induction as well as cellular T cell activation – increases the cytotoxic CD8+ cells, helper – CD4+ cells, number of activated CD38 + cells in peripheral blood and apoptosis receptor CD95 + expression on the surface of lymphocytes.

Non-specific immune cells like natural killer cells (NK) and monocytes/macrophages are also activated during RigVir therapy. The function of the lymph nodes is activated and infiltration of lymphocytes inside the tumor increases, which indicates that local immune activation processes are influenced by Rigvir.

Getting RigVir to work

RigVir may be used either through a systemic administration intramuscularly or locally (intra-tumoural or peri-tumoural) to bypass the tumor microenvironment’s barriers. Systemic intramuscular injections of RigVir are provided either closer to the localization of the primary tumor or – closer to the nearest metastatic foci (lymph collector or distant metastatic site). Usually, RigVir is injected either in the left or right shoulder or in the left or right buttock. Rigvir can also be used before, in-between or after radiotherapy and/or chemotherapy.

Like any other drug, RigVir may cause side effects. Existing evidence shows that there are very few side effects and no need for disruption of the treatment. So far there has not been registered any serious adverse effect. Generally, Rigvir is very well tolerated and observed side effects were mild and short-termed like temporary sub-febrility for 1-2 days after injection, sleepiness, mild gastrointestinal disturbances and seldom – pain at the site of injection.