Antiviral drugs

Viral infectious diseases are the most common diseases in the world. About 60% of infectious diseases are caused by viruses, and new viruses are constantly being discovered. They are highly contagious and have high mortality. They cause human health. Serious harm. Antiviral therapy is the fundamental treatment for viral infections. For acute infections, it can help alleviate symptoms and shorten the course of treatment. For chronic persistent infections, such as AIDS, hepatitis B, hepatitis C, etc., anti-virus is the root of treatment. Different viral infections cause different diseases and require different antiviral drugs. Although the development of genetic engineering and chemical synthesis of antiviral drugs over the years has provided more choices and opportunities for the clinical use of drugs that control viral infections, there are only a handful of antiviral drugs that have been proven to have clinical value. The certificate is also very limited. In particular, it is difficult to achieve some of the causes of chronic viral infections. Because the virus is an obligate intracellular parasite, its proliferation depends on the biosynthesis of the host cell, and the nucleic acid of some viruses is directly integrated into the gene of the host cell. Therefore, it is necessary to select antiviral drugs according to the characteristics of the virus and formulate an antiviral treatment policy. Antiviral drugs should selectively destroy or inhibit viruses inside and outside the cell, and do not cause lethal damage to cells, at least to uninfected cells. Therefore, it is difficult to inhibit the intracellular virus and achieve the clinical antiviral effect without adversely affecting the metabolism of the host cell. In addition, antiviral drugs are effective in protecting uninfected cells and in the early stage of infection, but the symptoms of viral infectious diseases are not specific, and it is difficult to diagnose early. When the clinical symptoms of viral infection occur, the virus proliferation in the body has been Achieve a certain degree. For example, in the clinical onset of influenza and Japanese encephalitis, a large number of viruses have proliferated and released in infected cells, and the body is in the stage of viremia or viremia, which has caused tissue damage. Effective viral suppression, although it is possible to control the further proliferation and spread of the virus, is often "too late" and has not been decisively therapeutic. Some of the syndromes caused by the virus are relatively common and relatively benign or self-limiting, so only drugs with a very high therapeutic index (the ratio of efficacy to toxicity) can be accepted. Therefore, it is still a very difficult task to vigorously develop and develop anti-viral drugs that are safe, effective, selective and easy to use.