Phase I study of erlotinib (E) for solid tumors in patients with hepatic or renal dysfunction (HD or RD): CALGB 60101

3026 Background: We sought to determine a tolerable dose and characterize the pharmacokinetics (PK) of E in patients with HD or RD. Methods: Patients with biopsy-proven solid tumors that commonly express EGFR, refractory to or without available standard therapy, performance status 0–2, and without biliary or renal obstruction were assigned to one of 3 cohorts (C): C1, AST ≥ 3 × ULN but no RD; C2, direct bilirubin 1–7 mg/dl but no RD; C3, creatinine 1.6–5.0 mg/dl but no HD. After slow accrual of 3 patients, an amended C1 for albumin < 2.5 g/dl accrued 3 additional patients. E was administered po daily in groups of at least 3 evaluable patients in escalating doses of 50, 75, 100, 150 mg starting with 50 mg in HD and 75 mg in RD. Patients had to take E for at least 4 weeks to be considered evaluable for toxicity unless dose-limiting toxicity (DLT) occurred sooner. DLT was defined as: grade 4 neutrophils or platelets; bilirubin ≥ 1.5 × baseline in C1/2 and ≥ 2.5 × ULN in C3; creatinine ≥ 2 × ULN in C1/2 and ≥ 2.5 × baseline in C3; grade ≥ 3 nausea,vomiting,diarrhea despite optimal supportive care; or any other grade ≥ 3 non-hematologic toxicity. Blood samples were obtained before and 1, 2, 3, 4, 6, 24 hrs after the first dose. Plasma E concentrations were measured by HPLC. A 2-compartment PK model was used to estimate total clearance of E. Results: Between 12/01 and 5/05, 55 patients were accrued but 1 never started therapy: male/female, 34/20; white/black, 46/8; median age 56 (range, 39–78); PS 0/1/2, 12/25/17. The distribution of treated/evaluable patients was: 6/5 in C1, 30/16 (attrition due to progressive disease) in C2, and 18/18 in C3. DLT consisted of both total and direct bilirubin ≥ 1.5 × baseline in 3 patients: C1, 1 of 5 at 50 mg; C2, 2 of 6 at 100 mg. In C2, 1 of 7 patients had grade 4 diarrhea/dehydration and grade 3 hypotension at 75 mg. No DLT was encountered in C3 with 12 patients at 150 mg. Clearance (mean ± SD) was cohort-dependent: 1.51 ± 0.64 (C1), 2.36 ± 1.17 (C2), 4.34 ± 2.53 (C3) l/hr; 2-sided exact Kruskal-Wallis p < 0.0006. Conclusions: Patients with RD tolerate 150 mg and appear to have normal clearance of E. Patients with HD should be treated at a reduced dose (i.e. 75 mg) consistent with their reduced clearance. [Table: see text]