Details of azithromycin fumarate

At present, the bioavailability of azithromycin, including tablets, capsules, dispersible tablets, granules, syrups and enteric-coated preparations, is 37%, far lower than that of roxithromycin (55%) and clarithromycin (45%). Because of its low blood concentration, relying on the special pharmacokinetic characteristics of azithromycin, that is, the intracellular drug concentration is much higher than the plasma drug concentration, and the lasting post-antibiotic effect, the therapeutic effect can be maintained for ten days only after taking the drug for three to five days, so the actual treatment cycle is the same as that of conventional antibiotics. In the process of using azithromycin, there is a difference between the administration cycle and the treatment cycle, which is not in line with people's general medication habits, and patients are often dissatisfied and affect the use. Even after taking azithromycin orally for three days, many patients are afraid to stop using it and switch to other drugs because the symptoms are not obvious. However, when they finally recovered, they thought that the efficacy of azithromycin was poor, so that a strange phenomenon rarely seen in history appeared in product evaluation, that is, high professional evaluation (correct use by professionals) and average patient response (misleading due to the medication habits of ordinary patients). It may also be related to the defects of azithromycin itself, that is, low blood concentration and slow onset are time-dependent drugs.

Azithromycin fumarate is a new generation of super antibiotics designed and carefully studied. It adopts the comprehensive research of chemical synthesis, biopharmaceuticals, physical pharmacy and other disciplines, and fundamentally solves several common defects of azithromycin in various dosage forms. The drug effect is enhanced by more than 1 times, the clinical curative effect is improved by more than 50%, the recovery course is shortened by about 40%, and the side effects of gastrointestinal tract and liver are reduced by nearly 50%. Especially suitable for the elderly and children. It is the only azithromycin preparation with high bioavailability successfully studied at home and abroad. Through the study of azithromycin fumarate, this study solved the following problems:

① Location and method of rapid absorption of azithromycin —— The blood concentration of azithromycin quickly reaches the peak within 1.2 hours after taking the drug, which is almost twice as high as that of Pfizer azithromycin tablets (reaching more than 400ng/ml), and the total bioavailability is expected to reach1.40% of that of ordinary azithromycin;

② Therapeutic effect; It can improve the effective rate and cure rate of the original indications, and may expand the range of sensitive bacteria and increase the indications of drugs due to the increase of blood drug concentration;

③ Aging; In the control study, the peak time of azithromycin tablets in Pfizer is less than 4 hours, while azithromycin fumarate tablets can reach the peak in only 1 hour, and the maximum concentration has exceeded nearly 100%. Clinical medication (azithromycin fumarate tablets) showed outstanding curative effect within 2 hours, especially for upper respiratory tract infection, mainly due to the increase of blood concentration and the substantial increase of free azithromycin, thus improving the curative effect;

④ the progress of sociology; Cmax of azithromycin fumarate tablets was higher than MIC and MPC (no colony formation concentration);

⑤ Improvement of pharmacodynamics; The original azithromycin is a time-dependent antibiotic, and its bacteriostatic effect is that the blood concentration is about 40% higher than the MIC time critical value, and it becomes bactericidal when it is higher than 60%. Cmax/MIC of conventional concentration-dependent antibiotics is 8- 12, the effective rate is 90%, and the satisfactory curative effect should be greater than 10. However, the Cmax of azithromycin fumarate tablets is doubled, and the more lethal it is to pathogenic bacteria, the faster it is.

According to the retrieval, there is no successful study on high bioavailability of azithromycin at home and abroad. As early as 1990s, in order to break through the limitation of low bioavailability, Pfizer made many studies on oral azithromycin, including the influence of gastric acid destruction on absorption, the determination of azithromycin in blood by liquid chromatography and titer plus cross-determination, the determination of absorption site of azithromycin by western blot, and the study of enteric-coated preparations. However, it failed to improve the absorption of the preparation. Since 1998, Shandong Chengchuang Pharmaceutical Technology Development Co., Ltd. has conducted a lot of in vitro and in vivo research, and successfully developed a new drug azithromycin fumarate tablet (250mg) with the trade name of Yi Song. Manufacturer: Dezhou Deyao Pharmaceutical Co., Ltd. National Medicine Standard H20030266. Product packaging: 6 tablets/box. And has filed an invention patent in China (patent has been filed for azithromycin fumarate bulk drug, and azithromycin fumarate composition has been authorized by China National Intellectual Property Administration). And there are plans to declare the project as an international patent.