In patients with moderate renal impairment, which is an estimated creatinine clearance (also called estimated glomerular filtration rate or eGFR) of 30 to 60 mL / minute, the dose is reduced to 150 mg nirmatrelvir (one 150-mg tablet) with 100 mg ritonavir (one 100-mg tablet), with both tablets taken together twice a day for 5 days.