Pharmacokinetics and safety of lobaplatin plus etoposide in Chinese men older than 65 years with extensive-stage small cell lung cancer: a phase II clinical trial

This phase II, multicenter, single arm clinical study was first performed to evaluate the therapeutic efficacy and safety of the regimen—a combination of lobaplatin (LBP) and etoposide (VP-16)—and investigate the pharmacokinetics of LBP in Chinese men older than 65 years with extensive-stage small cell lung cancer (SCLC). Patients older than 65 were treated with the combination of LBP and VP-16 for 4–6 cycles through intravenous drip. The initial dose of VP-16 was 100 mg/m2/day for d1-d3 in each 21-day cycle, while LBP was administrated for d1 in each cycle based on creatinine clearance (Ccr), 20 mg/m2 for Ccr < 60 mL/min; 25 mg/m2 for 60 ≤ Ccr < 80 mL/min and 30 mg/m2 for Ccr ≥ 80 mL/min. Efficacy, safety and pharmacokinetics were evaluated to confirm the therapeutic effect. Thirteen elderly patients were enrolled and three patients were discontinued. The median progress-free survival was 129 days and the median overall survival was 238 days, which caused a significantly prolonged survival rate of 38.5% and a higher disease control rate of 80%. Most frequent adverse events were mild to moderate containing leukopenia, neutropenia, anemia, nausea and anorexia. Pharmacokinetic analysis revealed that there is no significant difference between LP-D1 and LP-D2 at the same dosage level. With the dosage increasing, the elimination clearance showed a slowing tendency, especially for 30 mg/m2 group. LBP (20, 25, 30 mg/m2) in combination with VP-16 (100 mg/m2) could inhibit the elderly SCLC disease process, prolong their survival time and reduce adverse reactions via preliminary assessment and provide guidance for further investigation.