Microtracer-Based Assessment of the Mass Balance, Pharmacokinetics, and Excretion of [¹⁴C]Berzosertib, an Intravenous ATR Inhibitor, in Patients With Advanced Solid Tumors: A Phase 1 Study.

ABSTRACT: Berzosertib is a small-molecule ataxia telangiectasia and Rad3-related protein inhibitor. To assess the clearance mechanism(s) of berzosertib, a Phase 1, 2-period, open-label study was conducted in adults with advanced solid tumors who were treated with a single intravenous dose of 210 mg/m² berzosertib containing approximately 3 µCi of [¹⁴C]berzosertib (Period 1 Mass Balance), followed by assessment of berzosertib in combination with topotecan (Period 2 [Extension]) (NCT05246111). A total of 6 patients were enrolled in Period 1; 5 of them rolled over to Period 2. By Day 14, the mean total recovery of drug-related material (total radioactivity) in urine and feces combined was 89.5% (feces: 73.7%; urine: 15.8%). Pharmacokinetic data suggested that a substantial amount

SUBMITTER: Bolleddula J 

PROVIDER: S-EPMC12402879 | biostudies-literature | 2025 Sep

REPOSITORIES: biostudies-literature