Antiviral drugs are intended for the treatment of various viral diseases (influenza, herpes, HIV infection, etc.). They are also used for preventive purposes.
Depending on the disease and the properties of various antiviral agents used inside, parenteral or local (in the form of ointments, creams, drops).
The sources and chemical nature they are divided into the following groups: 1) interferons (endogenous origin and obtained by genetic engineering, their derivatives and analogues); 2) synthetic compounds (amantadine, Arbidol, bonafton, etc.); and 3) substances of plant origin (alpizarin, flakozid, etc.).
A large group of antiviral agents are derivatives of nucleosides (acyclovir, stavudine, didanosine, ribavirin, zidovudine, etc.).
One of the first nucleoside was idoxuridine, effectively crushes suppress the herpes simplex virus and vaccinia (vaccinal disease). However, side effects have limited its systemic application. In contrast, acyclovir, zidovudine, didanosine, and others appointed as chemotherapeutic agents (that is, expect resorptive effects). The mechanism of action of various nucleosides is very close. All of them are in cells infected with the virus, phosphorylated, transformed into nucleotides, compete with" normal " nucleotides for embedding into viral DNA and stop replication of the virus.
Interferons are a group of endogenous low molecular weight proteins (molecular weight from 15,000 to 25,000) with antiviral, immunomodulatory and other biological properties, including antitumor activity.
Currently known different types of interferon. The main ones are alpha interferon (with varieties alfa1 and alfa2), beta interferon, gamma interferon. Alpha interferon is a protein, and beta and gamma interferons are glycoproteins. Alpha interferon is produced mainly By b-lymphocytes of peripheral blood and lymphoblastoma lines, beta-interferon — fibroblasts, and gamma-interferon — T-lymphocytes of peripheral blood. Initially, natural (leukocyte human) interferon was used for the prevention and treatment of influenza and other viral infections. Recently, a number of recombinant alpha interferon (Interlock, Reaferon, interferon alpha-2A, interferon alpha−2B, etc.), beta interferon (interferon beta, interferon beta−1B, etc.), gamma interferon (imukin, etc.) were obtained by genetic engineering. Effects of some antiviral drugs (Poludan, kridanimoda, partly Arbidol, etc.) related to their interferonogenic activity, i.e. the ability to stimulate the formation of endogenous interferon.
Wide application for the treatment and prevention of influenza and other viral illnesses are rimantadine, adapromin and others (derivative of amantadine), metisazon, bonafton.