Renally Cleared Drugs: ADMET Fundamentals, Dose Adjustment in Renal Impairment, and Their Role in Clinical Pharmacokinetics and Toxicology

Drugs eliminated predominantly through renal excretion, whether by glomerular filtration alone or in combination with active tubular secretion, present a distinctive dose-adjustment challenge across the spectrum of renal function, since declining renal function can reduce clearance substantially enough to require dose or interval modification well before a patient reaches dialysis-dependent kidney failure (U.S. Food and Drug Administration, 2020). This article examines the ADMET fundamentals specific to this drug category, the assays and clinical study designs used to characterize renal elimination mechanisms and renal transporter involvement, the regulatory framework governing renal impairment studies, and the dose-adjustment strategies this drug category typically requires. The article closes with recommendations for regulatory affairs and clinical pharmacology professionals developing a renally cleared drug program.Keywords: renal clearance; glomerular filtration; tubular secretion; renal impairment; organic anion transporter; creatinine clearance; regulatory artificial intelligence