a. Hepatitis B screening is mandatory for all patients (HBsAg and anti-HBc). Patients with active hepatitis B disease should not be treated with obinutuzumab. Patients should be referred to a specialist if they are carriers before treatment starts (see PI or SmPC). Subjects who are positive for anti-HBc and/or anti-HBs but negative for HBsAg and HBV DNA may be treated after consultation with a hepatologist.