US drug regulatory authorities have issued revised safety information for the protease inhibitor darunavir (Prezista)/ritonavir.
The Food and Drug Administration’s revision now means that the patient information leaflet in packets of darunavir cautions that 0.5% of patients taking darunavir/ritonavir during its clinical development were diagnosed with drug-induced hepatitis. Patients with pre-existing liver problems, including hepatitis B or hepatitis C infection, had a greater risk of developing such a complication.
European product information already includes a similar caution.
No adjustment in the dose of darunavir/ritonavir is recommended for patients with mild or moderate liver problems, but the US product label now notes that the drug is not recommended for patients with severe liver problems.
Liver function should be monitored in all patients before treatment with darunavir/ritonavir is started, and monitoring of ALT/AST levels should be increased in patients with pre-existing liver problems during the first few months of therapy with the drug.
If a patients experiences a worsening of their liver function, or if they develop symptoms suggestive of drug-induced hepatitis (tiredness, weight loss, nausea, yellowing of the skin, dark urine, pain in the liver, or an enlarged liver) doctors are recommended to consider either interrupting or stopping treatment with the darunavir/ritonavir.