The European Commission granted a marketing authorisation valid throughout the European Union for Dutrebis on 26 March 2015. Dutrebis contains the active substances lamivudine and raltegravir and is only for use in patients whose infection is not resistant to these medicines or certain related antiviral medicines.

The active substances in Dutrebis are already available in the European Union (EU) as single-component medicines: lamivudine as Epivir since 1996, and raltegravir as Isentress since 2007.The drug is used to treat patients infected with human immunodeficiency virus type 1 (HIV-1). It is used together with other HIV medicines and can be used in patients from 6 years of age and weighing at least 30 kg.

Dutrebis is available as tablets containing 150 mg of lamivudine and 300 mg of raltegravir, and the recommended dose is one tablet twice a day. Dutrebis must be used in combination with other HIV medicines. The two active substances in Dutrebis act by blocking different stages of the process by which the HIV virus replicates itself in the body. One active substance, lamivudine, is a ‘nucleoside reverse-transcriptase inhibitor’ (NRTI). It works by blocking the activity of reverse transcriptase, an enzyme needed by HIV to produce the genetic instructions for making more viruses once it has infected the cell. The other active substance, raltegravir, is an ‘integrase inhibitor’. It blocks an enzyme called integrase that is needed for the subsequent stage of virus replication. Dutrebis reduces the amount of HIV in the blood and keeps it at a low level. It does not cure HIV infection or AIDS, but it can hold off damage to the immune system and avoid the development of infections and diseases associated with AIDS.

Because lamivudine and raltegravir are already approved individually to treat HIV infection, the company presented data from the studies used to approve these medicines, including a study involving 160 patients given raltegravir with lamivudine (plus another HIV medicine, tenofovir) for a total of 240 weeks. The main measure of effectiveness was the proportion of patients with a reduction of the levels of virus in the blood (viral load) to fewer than 50 copies of HIV RNA per ml, which was 68.8%.

The company also looked at the way Dutrebis was absorbed in the body in comparison with two separate tablets containing lamivudine and raltegravir. The results of the studies showed that Dutrebis produced similar levels lamivudine in the body to lamivudine taken separately; although the levels of raltegravir were slightly different, Dutrebis was shown to produce levels of raltegravir that were similarly effective in controlling the virus. The most common side effects with lamivudine or raltegravir (which may affect up to 1 in 10 people) are headache and nausea. Other common side effects with lamivudine are malaise, tiredness, nasal signs and symptoms, diarrhoea and cough.