Neuraminidase inhibitors
Neuraminidase inhibitors (also neuraminidase inhibitors , abbr. NI ) or inhibitors of neuraminidase are virustatic acting drugs that that surface protein inhibit that the antigenicity of various bacteria and viruses also determined. The influenza virus binds to the surface of the host cell via viral hemagglutinin , then penetrates the cell and then reproduces inside the cell by reprogramming the cell to produce the virus multiple times. The newly formed viruses later bud on the cell surface, but initially remain bound to the cell via receptors . With the help of the viral neuraminidase this bond is broken. The viruses are finally released and can immediately infect other cells . However, neuraminidase inhibitors block neuraminidase - usually by binding to the active center of neuraminidase - so that the viruses cannot break away from the host cell and continue to spread in the body.
Representative
The first active ingredient in this class of substances to be approved for the treatment of influenza was zanamivir , which GlaxoSmithKline sells as Relenza ®. It must be inhaled and can be in people with bronchial asthma or COPD to bronchospasm lead.
Oseltamivir - marketed as Tamiflu ® by Hoffmann-La Roche - has the advantage of being taken orally as a capsule or suspension , which allows the drug to be distributed through the bloodstream and, when taken appropriately, enables sufficient and constant amounts at all locations where the virus replicates. It is also approved for children from the age of 1 in therapy and from 13 years of age in prophylaxis .
effectiveness
The diagnosis of influenza can often only be made precisely after a virological diagnosis , since very often comparatively banal infections such as colds , also known as so-called " flu infections ", can cause flu-like symptoms, especially at the beginning of the illness. In contrast to influenza, also known as “real flu”, such infections are caused by completely different viruses and can therefore not be successfully treated with neuraminidase inhibitors, as these viruses do not contain neuraminidase. Therefore, before using a neuraminidase inhibitor, with regard to its possible effectiveness, for a precise diagnosis of influenza, in addition to the exact diagnosis of symptoms, if necessary, a smear test to reliably determine the causative virus, in order to differential diagnosis of a flu infection or a pandemic -Virus distinguish reliably
In 2014, however, research by the Cochrane Collaboration revealed doubts about the effectiveness and safety of the neuraminidase inhibitors oseltamivir and zanamivir. The meta-analysis found that treatment with zanamivir in adults reduced the duration of the illness from 6.6 to 6 days. However, zanamivir had no effect on the incidence of severe forms of disease such as pneumonia or bronchitis. The same meta-analysis found that treatment with oseltamivir in adults reduced the duration of the illness from 7 to 6.3 days. However, oseltamivir had no effect on the frequency of severe forms of disease such as pneumonia or bronchitis and could not reduce the proportion of patients who had to be hospitalized. Furthermore, the intake of oseltamivir caused undesirable drug effects such as nausea, vomiting and, with prophylactic use, headaches, psychiatric and kidney-damaging effects.
Individual evidence
- ↑ a b c d e f Tom Jefferson, Mark A Jones, Peter Doshi et al .: Neuraminidase inhibitors for preventing and treating influenza in healthy adults and children. In: British Medical Journal . 2014, online pre-publication of April 10, 2014, doi: 10.1002 / 14651858.CD008965.pub4 .
