New Hepatitis C treatment method: Block micro-RNA
Hepatitis was declared a blockade
Alexandra Borisova, Newspaper.RuA new way to combat the hepatitis C virus has been found. Instead of directly affecting it, scientists propose to block the RNA molecules that are responsible for the reproduction of the virus.
The effectiveness of this therapy is ten times higher than current treatment methods.
According to the World Health Organization, about 3% of the world's population is infected with the hepatitis C virus, and about 170 million are chronically ill. In the future, they risk becoming victims of cirrhosis of the liver or liver cancer. Approximately 3-4 million Americans (more than 1% of the population) are such chronic patients, and their number is growing by 40 thousand per year. There are about 4 million chronic patients in Europe.
A study published this week in Science (Robert E. Lanford et al., Therapeutic Silencing of microRNA-122 in Primates with Chronic Hepatitis C Virus Infection) shows that the drug SPC3649, a qualitatively new therapy aimed at micro-RNA, makes it possible to cure the hepatitis C virus.
The drug was developed by pharmacists from Santaris Pharma A/S, which is a pioneer in clinical research of MRNA and micro-RNA-directed therapy. RNA-directed therapy is considered the key to the treatment of diseases such as metabolic disorders, infectious and inflammatory processes, cancer, as well as rare genetic diseases.
During preclinical experiments, SPC3649 successfully suppressed the function of miR-122, a micro–RNA expressed in the liver, which plays an important role in the replication of hepatitis C virus. As a result, the liver of chimpanzees suffering from chronic hepatitis C became healthier. The number of virus-infected cells both in the liver and in the blood has sharply decreased.
Two sick animals received 5 mg / kg of the drug per week, two more – 1 mg / kg. The treatment lasted 12 weeks, it was preceded by 17 weeks, when no therapy was performed at all. Animals receiving 5 mg/kg showed good dynamics in the fight against the disease. The level of viruses has decreased by about 350 times.
The action of RNA-directed drugs is based on synthetically modified analogues of human ribonucleic acid. As a result, the resulting Locked nucleic acids (LNA) are similar in structure to RNA. They increase the resistance of nucleic acids to metabolism. LNA drugs are introduced into a variety of tissues, increasing the body's stability.
"This medicine works exceptionally well as long as we observe it in the treatment of chimpanzees. Today, the standard is therapy with pegylated interferon in combination with ribavirin. But it is effective only in 50% of patients and often causes severe side effects. SPC3649 operates by a completely different mechanism, so it is more tolerant to uninfected cells of the body. If further trials are also successful, it can replace the traditional interferon or act in combination with it, significantly increasing the effectiveness of treatment," said Robert Lanford, the first author of the publication.
What is especially important, the effectiveness of SPC3649 remained after the end of its use. Over the next few months, there were no adverse events and no signs of recovery of the virus activity.
This distinguishes the new RNA-directed drug from the current antiviral therapy. Conventional therapy does not have long-term effectiveness, since the virus constantly mutates and develops resistance to the injected drug. Blocking of micro-RNA-122 stops virus replication without any selection of stable or unstable mutant forms of the virus.
Clinical trials of SPC3649 have now begun. They are undergoing the first phase – testing on healthy volunteers.
Portal "Eternal youth" http://vechnayamolodost.ru04.12.2009