Pharmacokinetic Boosting of Osimertinib

Cobicistat will be added to the treatment with osimertinib. The initial dose will be 150 mg cobicistat, which equals the dose used in the treatment of HIV-infected patients. If this dose is well tolerated and the increase in exposure of osimertinib is not sufficient, the dose of cobicistat will gradually be escalated to 600 mg per day (150 mg cobicistat, four times per day).