Rezolsta

Rezolsta can only be obtained with a prescription and treatment should be started by a doctor experienced in managing HIV infection. Rezolsta is available as tablets that contain 800 mg of darunavir and 150 mg of cobicistat. The recommended dose is one tablet a day, taken with food. For more information about using Rezolsta, see the package leaflet or contact your doctor or pharmacist.

Rezolsta contains two active substances. Darunavir is a protease inhibitor. It blocks an enzyme called protease, which the virus needs to make new copies of itself. When the enzyme is blocked, the virus does not reproduce normally and its increase and spread slows down. Cobicistat acts as a ‘booster’ to enhance the effects of darunavir, by prolonging its activity in the body.

Rezolsta, taken in combination with other HIV medicines, reduces the amount of HIV in the blood and keeps it at a low level. Rezolsta does not cure HIV infection, but it can delay or reverse the damage to the immune system and the development of infections and diseases associated with AIDS.

Darunavir is currently authorised as Prezista and cobicistat as Tybost.

Because darunavir and cobicistat have both previously been shown to be effective and are authorised for the treatment of HIV infection, studies were mainly carried out to show that Rezolsta produced similar effects and levels of darunavir in the blood to the two active substances given separately, and to darunavir given with a different booster medicine, ritonavir (an established combination).

In addition, one main study examined the safety and effectiveness of darunavir and cobicistat given with other HIV medicines, in 313 adults with HIV who had not been treated previously or who had been treated and whose infection was not expected to be resistant to darunavir. Effectiveness was measured by a reduction in viral load (the amount of HIV-1 virus in the blood) to less than 50 copies/ml. Overall, 258 patients (82%) achieved this response after 24 weeks of treatment, and 253 patients (81%) at 48 weeks, which was comparable to results with darunavir plus ritonavir.

Further data indicated that darunavir and cobicistat also led to acceptable reductions in the viral load in adolescents between 12 and 17 years of age.

The most common side effects with Rezolsta (which may affect more than 1 in 10 people) are diarrhoea, nausea (feeling sick), headache and rash. The most serious side effects were rash, diabetes, hypersensitivity (allergic) reactions, vomiting, Stevens-Johnson syndrome (life-threatening reaction with flu-like symptoms and painful rash affecting the skin, mouth, eyes and genitals) and immune reconstitution syndrome. With immune reconstitution syndrome, the patient’s immune system starts working again and fights existing infections (causing inflammation) and may attack healthy tissue such as the liver and thyroid gland. For the full list of all side effects of Rezolsta, see the package leaflet.

Rezolsta must not be taken by patients who have severely reduced liver function. It must also not be used with certain other medicines as they may reduce the effectiveness of treatment or increase side effects. For the full list of restrictions, see the package leaflet.

The European Medicines Agency decided that Rezolsta’s benefits are greater than its risks and recommended that it can be authorised for use in the EU. Both active substances have already been shown to be effective, and combining them into a single tablet was considered to be more convenient than taking them separately, reducing the risk of errors. There was no evidence of unexpected side effects.

Recommendations and precautions to be followed by healthcare professionals and patients for the safe and effective use of Rezolsta have been included in the summary of product characteristics and the package leaflet.

As for all medicines, data on the use of Rezolsta are continuously monitored. Side effects reported with Rezolsta are carefully evaluated and any necessary action taken to protect patients.

Rezolsta received a marketing authorisation valid throughout the EU on 19/11/2014.