Why can Tamiflu resist h 1n 1 Gankang?

The listing of oseltamivir CASRN is 1999 in Switzerland and 200 1 10 in China. Its chemical name is (3R, 4R, 5s)-4- acetamide -5- amino -3( 1- ethylpropoxy). After oral administration, oseltamivir is rapidly converted into its active metabolite oseltamivir carboxylic acid through liver and intestinal esterase. The configuration of oseltamivir carboxylic acid is similar to the transition state of neuraminic acid, and it can competitively bind to the active site of influenza virus neuraminidase (NA, also known as neuraminidase), so it is a potent and highly selective NA inhibitor (NAIs) of influenza virus, which mainly interferes with the release of virus from infected host cells.

Tamiflu currently on the market is an exclusive anti-influenza drug produced by Roche Pharmaceuticals. Its common name is oseltamivir phosphate, which is the aforementioned phosphate of oseltamivir. The chemical registration number is CASRN 204255- 1 1-8. Tamiflu was approved for listing by FDA on 1999, and was listed in China in July 2004. From the perspective of pharmacoeconomics, although the use cost of Tamiflu is not low, the retail price of Tamiflu is equivalent to 60 yuan every day, and a course of treatment for five days is equivalent to 300 yuan. However, Tamiflu is a very effective drug to treat influenza, which can greatly reduce the occurrence of complications (mainly tracheobronchitis, pneumonia, pharyngitis, etc.). ) and the use of antibiotics, so it is one of the most commonly used drugs to treat influenza at present, and it is also recognized as one of the most effective drugs against avian influenza and swine influenza (A/H 1N 1 virus).

Japanese health authorities launched an investigation into the possible side effects of Tamiflu, an anti-influenza drug. At midnight on February 26th, 2007, a boy of 14 years old jumped from the 1 1 floor of an apartment building in Sendai after taking Tamiflu, which was the death of 18 boy related to this best-selling drug in Japan in the past 17 months. In this latest death case, the boy's doctor asked him to take Tamiflu for five consecutive days. On the 26th, the boy ate two tablets of Tamiflu. That night, he woke up and told his mother that he was going to the bathroom, but then he opened the front door and went out. His mother felt something was wrong, so she followed. She cried when she saw him climb the railing 1.3 meters high. The police said that the boy jumped without any response. The police said they didn't think the boy wanted to commit suicide.

Two weeks ago, a 14-year-old girl jumped from an apartment building in Pu Jun, Aichi Prefecture and died after taking Tamiflu. At present, the Japanese Ministry of Health, Labor and Welfare has asked the manufacturers of imported Tamiflu to collect the health status of patients who have taken this anti-influenza drug. After the incident, Japanese Minister of Health, Labor and Welfare Yanagisawa Hakuo appealed to the public to remain calm. He said, "We need hard evidence." According to the Ministry of Health, Labor and Welfare, pharmaceutical companies reported that 54 people who took Tamiflu had died in Japan as of last June 165438+ 10.

The US Food and Drug Administration (FDA) warned in June last year 165438+ 10 that Tamiflu may cause serious side effects such as insanity, hallucinations and even death to patients, especially children. The bureau suggested revising the instructions of Tamiflu in the United States, and advised doctors and parents to read the instructions carefully after taking the medicine and closely observe the patients.

But Roche, a Swiss pharmaceutical company that produces this drug, said that the death rate caused by the side effects of Tamiflu is not higher than that of flu victims.

Tamiflu's raw materials

With the development of the global H5N 1 subtype highly pathogenic avian influenza epidemic, the Chinese government and enterprises are stepping up the reserve and production of anti-avian influenza drugs respectively. Tamiflu produced by Roche, Switzerland, is in a leading position in the reserve of anti-avian influenza drugs in many countries around the world and has become the most effective pre-treatment drug recommended by the World Health Organization. Tamiflu is also one of the main drugs in Chinese mainland's planned avian influenza drug reserve.

90% shikimic acid, the main raw material of Tamiflu, comes from Chinese mainland. Roche claimed to relax the production license, and mainland enterprises in China actively requested to cooperate with Roche to produce Tamiflu locally or to develop and produce products similar to Tamiflu. However, Shaanxi Hui Ke Plant Development Co., Ltd., the first enterprise in xi to produce shikimic acid, has stopped producing shikimic acid for a simple reason: star anise, the raw material for extracting shikimic acid, can't be bought. In addition, the shikimic acid production lines of Xi Antaihua Natural Bio-pharmaceutical Co., Ltd., Xi Anyi Bio-pharmaceutical Co., Ltd. and Xi Indjeff Pharmaceutical Co., Ltd. also stopped running.

After Tamiflu is considered as the most effective drug for avian influenza so far, the demand for Tamiflu in the global market has expanded, and shikimic acid, the main raw material of Tamiflu, has suddenly become a hot commodity, and the price has increased several times. It is understood that shikimic acid was mainly used for drugs such as tumors and anti-inflammation, and the market demand was not great. There are only a handful of enterprises engaged in shikimic acid refining, mainly concentrated in Xi 'an, and the scale of enterprises is generally small. Moreover, shikimic acid is considered as a secondary product in almost every company's product structure and is not in a dominant position. The most popular influenza A (swine flu) is H 1N 1, and oseltamivir is effective at the initial stage of infection.