The substance Darunavir is a drug that is characterized by its antiviral properties. The drug belongs to the category of HIV protease inhibitors and is used primarily as part of the drug therapy of infections with the HI virus type 1. The effect of Darunavir is mainly due to the fact that it impairs the viral protease. This is essential for the replication of viruses.
What is darunavir?
The active ingredient darunavir is a so-called virustatic agent and is counted among the HIV protease inhibitors. The drug is suitable for the treatment of HIV-1 infection. It can be used in adult patients as well as in children whose weight exceeds 20 kilograms. As a rule, the drug darunavir is administered in the form of tablets. In addition, oral suspensions of the active substance are also available on the pharmaceutical market. The substance darunavir was approved as a drug in Switzerland in 2006, where it is available under the trade name Prezista. In addition, a combination preparation of darunavir and the substance cobicistat was approved in 2016. This drug is available on the market under the name Rezolsta. In the context of pharmaceutical use, darunavir ethanolate is used. This substance is a powder of white color. The structure of this substance is non-peptidic.
Pharmacological action
The drug substance darunavir is characterized by a typical mode of action. Primarily, the antiviral effects of the substance darunavir are relevant for its action. For this reason, the drug is used in the therapy of infections with HIV-1. The effectiveness of the substance is primarily due to the fact that it inhibits the so-called HIV protease. This is particularly important for the maturation processes of the viruses and their reproduction. The active ingredient darunavir in combination with the substance ritonavir has a half-life of approximately 15 hours. In the majority of cases, the drug is administered orally. The drug Darunavir is administered in the form of tablets. Following ingestion, the concentration of the active ingredient in the blood increases and binds to 95 percent of the proteins in the blood plasma. The substance is then metabolized by the hepatic route, i.e. in the liver. Overall, the plasma half-life is about 15 hours on average. In principle, darunavir leads to a blockade of the HIV protease. As a consequence, only non-infectious forms of viruses are produced. This prevents new cells from becoming infected with the virus. The tablets are taken either once or twice a day. The active ingredient darunavir is usually used with a so-called pharmacokinetic booster, for example cobicistat or ritonavir. These substances are CYP inhibitors and slow down the breakdown of the drug. Basically, the drug darunavir is a substrate of the substance CYP3A4.
Medicinal use and application
The drug darunavir it is mainly suitable for drug therapy of infections with HIV-1. To increase the efficacy of the substance, the drug darunavir is combined in many cases with the boosters ritonavir or cobicistat. The boosters are only used in low doses. They inhibit the metabolization and degradation of the drug. In principle, the dosage of the drug darunavir is given in accordance with the enclosed specialist information. The film-coated tablets are taken once or twice a day together with meals.
Risks and side effects
There are many potential side effects and discomforts while taking the active ingredient darunavir. However, these do not manifest to the same extent in all patients and vary in terms of their frequency and individual severity. Most commonly, the drug darunavir causes side effects such as headaches and rashes on the skin, as well as digestive disturbances. These gastrointestinal complaints manifest themselves, for example, in the form of nausea, pain in the abdominal area, vomiting and diarrhea. In addition, severe fatigue and sleep disturbances are possible in some cases during ingestion. The skin may show allergic reactions such as reddened areas or itching. Asthenia is also possible during therapy.In addition to potential complaints caused by taking the drug darunavir, some contraindications must also be taken into account. It is therefore important for the attending physician to take a thorough medical history in order to keep the risk of complications as low as possible. For example, treatment with the drug Darunavir should be avoided in cases of known hypersensitivity to the active substance, severe kidney weakness or liver function disorders. In addition, various interactions with other drugs must be taken into account. For example, interactions of the active substance with CYP inhibitors and substrates are possible. All information regarding contraindications can be found in the enclosed SmPC.
