Artesunate is an active ingredient used to treat malaria. The tropical infectious disease is caused by pathogens of the genus Plasmodium and claims 1 million lives worldwide each year. As studies show, the active ingredient could also be used in the future to treat malignant – that is, malignant – tumors.
What is artesunate?
Artesunate is an active ingredient used to treat malaria. The drug artesunate belongs to the antiprotozoal drug class and is made from the plant derivative of the annual mugwort (Artemisia annus). The artesiminin contained in the leaves and flowers of the mugwort has been used in traditional Chinese medicine for thousands of years. In recent years, the active plant ingredient has also become the focus of Western medicine. In 2002, the artesunate synthesized from it was included by the WHO in the list of essential medicines. The drug is mostly used against malaria tropica with the pathogen Plasmodium falciparum, which is characterized by a severe course. Artesunate is also highly effective against multidrug-resistant malaria pathogens that no longer respond to common antimalarial drugs.
Pharmacologic action
Malaria is transmitted by the bite of the Anopheles mosquito. The pathogens first settle in the liver, infect red blood cells (erythrocytes), and destroy them. The active ingredient artesunate enters directly into the mitochondria of the pathogen cell. Mitochondria are found in all cells and are the “productive powerhouse” of every cell. The so-called peroxide bridges in the chemical structure of the active ingredient play a decisive role in the pharmacological-biological efficacy of artesunate. They release a high concentration of oxygen radicals that attack the mitochondria and cause the cell death of the pathogen. The drug is also effective against cancer cells. Tumor cells contain iron ions in high concentration. They react chemically with the oxygen radicals and cause the cell to die. Artesunate also appears to be able to prevent the formation of blood vessels that supply the tumorous tissue. It thus counteracts the formation of metastases. Due to a slightly altered basic biochemical structure, the derivative artesunate shows a much higher bioavailability than the original substance artesiminin. Bioavailability indicates how quickly and to what extent a drug is absorbed by the organism and made available to the body. Artesunate has a very short half-life. It is rapidly metabolized by the liver and excreted from the body in a few hours.
Medical use and application
Particularly in severe cases, the artesiminin derivative significantly reduces the mortality rate of those suffering from malaria. Of 1,000 malaria patients treated with artesunate, only 147 died instead of 241 of those treated with the common antimalarial drug quinine. Until now, artesunate-containing drugs have been used exclusively in adults. Recent studies show that children may soon also benefit from the active ingredient. Various studies indicate that artesunate could also be used in cancer therapy in the future. For example, it has been shown that the active ingredient is a promising drug for malignant tumors. Cancer cells have little resistance to the oxidative stress caused by oxygen radicals. The drug is particularly effective in fast-growing tumors. They have a particularly high number of iron ions. Scientists from Singapore also attribute to the substance a better efficacy against asthma than commonly prescribed corticosteroids. Artesunate is usually used against malaria as a combination preparation to prevent possible resistance. The drug is usually administered intravenously as an infusion for severe malaria tropica, but it is also available in tablet form.
Risks and side effects
The effect of artesunate is selective. That is, it has a toxic effect on tumor cells and malaria pathogens that contain very high levels of iron, but it has no negative effects on healthy cells. The drug artesunate is considered to be well tolerated. The side effects known to date are limited and can generally be well controlled. The side effects associated with taking artesunate also depend on the drug combination in which it is available. The most common side effects are headache, insomnia, drowsiness and weakness – but nausea, vomiting and diarrhea can also occur.In rare isolated cases, hemolysis – the dissolution of red blood cells – occurs, resulting in anemia.
