Active Substance: fidaxomicin
Common Name: fidaxomicin
ATC Code: A07AA12
Marketing Authorisation Holder: Astellas Pharma Europe BV
Active Substance: fidaxomicin
Authorisation Date: 2011-12-05
Therapeutic Area: Clostridium Infections
Pharmacotherapeutic Group: Anti-infectives for systemic use
Dificlir is indicated in adults for the treatment of Clostridium difficile infections (CDI) also known as C. difficile-associated diarrhoea (CDAD).
Consideration should be given to official guidelines on the appropriate use of antibacterial agents.
What is Dificlir?
Dificlir is a medicine that contains the active substance fidaxomicin. It is available as tablets (200 mg).
What is Dificlir used for?
Dificlir is used to treat adults with infections of the gut caused by bacteria called Clostridium difficile. The medicine can only be obtained with a prescription.
How is Dificlir used?
The recommended dose is one tablet twice a day (every 12 hours) for 10 days.
How does Dificlir work?
C. difficile are bacteria that are present naturally in the gut and do not cause any problems in healthy people. However, some antibiotics that are used to treat infections can interfere with the balance of 'good' bacteria in the gut. When this happens, C. difficile bacteria can multiply and produce toxins (poisons), which cause illness such as diarrhoea and fever. At this point, a person is said to be infected with C. difficile.
The active substance in Dificlir, fidaxomicin, is an antibiotic that belongs to the class of macrocylic antibiotics. When it is swallowed most of the active substance does not get absorbed into the blood stream but acts locally on C. difficile bacteria in the gut. It works by blocking the bacterial enzyme RNA polymerase, which is used to produce the RNA that the bacteria need to make proteins. This stops the C. difficile bacteria from growing and multiplying.
How has Dificlir been studied?
The effects of Dificlir were first tested in experimental models before being studied in humans.
Dificlir has been compared with vancomycin (another antibiotic for C. difficile infections) in two main studies involving a total of 1,147 adult patients with mild to moderately severe C. difficile infection. The main measure of effectiveness was the number of patients that were cured after 10 days of treatment.
What benefit has Dificlir shown during the studies?
Dificlir was at least as effective as vancomycin in curing C. difficile infection. When looking at the results of the two studies, 92% of patients on Dificlir were cured compared with 90% of patients on vancomycin.
What is the risk associated with Dificlir?
The most common side effects with Dificlir (seen in between 1 and 10 patients in 100) are nausea (feeling sick), vomiting and constipation. For the full list of all side effects reported with Dificlir, see the package leaflet.
Dificlir must not be used in people who are hypersensitive (allergic) to fidaxomicin or any of the other ingredients.
Why has Dificlir been approved?
The CHMP considered that Dificlir was effective in curing C. difficile infections and was generally well tolerated with side effects that are similar to vancomycin. The CHMP noted however, that there are uncertainties about the effects of Dificlir in certain groups of patients such as those with liver and kidney problems and recommended that further studies in this group should be carried out. The CHMP considered the severity of C. difficile infections and the drawbacks of current treatments and concluded that benefits of Dificlir are greater than its risks and recommended that it be given marketing authorisation.
Other information about Dificlir
The European Commission granted a marketing authorisation valid throughout the European Union for Dificlir on 5 December 2011.
For more information about treatment with Dificlir, read the package leaflet (also part of the EPAR) or contact your doctor or pharmacist.