Hepatic safety analysis of trabectedin: results of a pharmacokinetic study with trabectedin in patients with hepatic impairment and experience from a phase 3 clinical trial

Purpose Trabectedin is metabolized by the liver and has been associated with transient, noncumulative transaminase elevation. Two recent studies further characterize hepatic tolerability with trabectedin therapy: a phase 1 pharmacokinetic study (Study #1004; NCT01273493) in patients with advanced malignancies and hepatic impairment (HI), and a phase 3 study (Study #3007; NCT01343277) of trabectedin vs. dacarbazine in patients with advanced sarcomas and normal hepatic function. Methods In Study #1004, patients received a single 3-h intravenous (IV) infusion of trabectedin: control group, trabectedin 1.3 mg/m²; HI group (baseline total bilirubin >1.5 and ≤3× upper limit of normal [ULN]; AST and ALT ≤2.5× ULN), trabectedin 0.58 or 0.9 mg/m². In Study #3007, the trabectedin group received 1.5 mg/m² by 24-h IV infusion every 3 weeks until disease progression or unacceptable toxicity. Results In Study #1004, dose-normalized trabectedin exposure was higher in HI patients (n = 6) versus controls (n = 9) (geometric mean ratios [90% CI] AUC_last: 1.97 [1.20; 3.22]). In Study #3007, following trabectedin administration, 90% of patients had elevated ALT (32% grade 3–4) and 84% had elevated AST (17% grade 3–4). Transaminase elevations were transient and noncumulative. Progression-free survival was similar in patients with grade 3–4 hepatotoxicity (n = 109) versus grade 0–2 hepatotoxicity (n = 231) (median [95% CI]: 4.63 [4.01, 5.85] months versus 3.55 [2.73, 4.63] months; P = 0.545, HR = 0.91 [0.68–1.23]). Conclusion Trabectedin treatment of patients with HI results in higher plasma exposures. Hepatotoxicity in patients with normal liver function can be effectively addressed through dose reductions and delays.