Phase I study of carboplatin in combination with PM00104 (Zalypsis®) in patients with advanced solid tumors.

This phase I trial determined the recommended dose for phase II trials (RD) of carboplatin 1-h intravenous (i.v.) infusion followed by PM00104 1-h i.v. infusion on Day 1 every 3 weeks (q3wk) in adult patients with advanced solid tumors. A toxicity-guided, dose-escalation design was used. Patients were stratified and divided into heavily (n = 6) or mildly pretreated (n = 14) groups. Transient grade 4 thrombocytopenia (in one heavily and three mildly pretreated patients) was the only dose-limiting toxicity (DLT) observed. Carboplatin AUC3-PM00104 2.0 mg/m(2) was the RD in both groups. At this RD, the carboplatin AUC was equal to ~60 % the target AUC used in other combinations, and the PM00104 dose intensity was 56-67 % of the value achieved at the RD for single-agent PM00104 given as 1-h infusion q3wk. Most treatment-related adverse events were grade 1/2. They mainly consisted of gastrointestinal and general symptoms, such as fatigue, anorexia, mucosal inflammation or nausea. Transient neutropenia (50 % of patients) and thrombocytopenia (33-38 %) were the most common severe hematological abnormalities; their incidence was higher than with single-agent PM00104. No pharmacokinetic drug-drug alterations occurred. Partial response was found in one patient with triple negative breast cancer pretreated with paclitaxel/bevacizumab. Three patients with colorectal cancer, head and neck cancer, and tumor of unknown origin had disease stabilization for ≥3 months. In conclusion, no optimal dose was reached due to overlapping myelosuppression despite stratification according to prior treatment. Therefore, this carboplatin plus PM00104 combination was not selected for further clinical research.

A phase I and pharmacokinetic study of plitidepsin in children with advanced solid tumours: an Innovative Therapies for Children with Cancer (ITCC) study.

AIMS: To determine the maximum tolerated dose, the recommended dose (RD) for phase II studies, dose-limiting toxicities and pharmacokinetics (PK) for plitidepsin administered as a 3-h intravenous infusion every 2weeks (one cycle) to children with refractory or relapsed solid tumours. METHODS: Consecutive cohorts of patients were treated according to a standard '3+3' design with escalating doses of plitidepsin at 4, 5 and 6mg/m(2). Additional 15 patients were recruited at the RD to further evaluate safety and pharmacokinetic associations with respect to age, dose level and toxicity. RESULTS: Thirty-eight of 41 patients registered received plitidepsin. Dose-limiting toxicities during the first three treatment cycles related to myalgia, elevated creatine phosphokinase, transaminase increase and nausea/vomiting. The RD for plitidepsin is 5mg/m(2). PK analyses revealed high inter-patient variability in plasma, but a similar clearance of plitidepsin in children and adolescents. One partial response confirmed at 4weeks in a patient with neuroblastoma and one unconfirmed partial response in a pancreatoblastoma were observed; four other patients with neuroblastoma, medulloblastoma, glioblastoma and rhabdoid tumour had disease stabilisations lasting ⩾3months. CONCLUSION: Plitidepsin administered to children as a 3-h infusion every 2weeks is received with manageable toxicity for children with cancer, and the RD is 5mg/m(2). Pharmacokinetic parameters in children and adolescents are comparable to adults. Future phase II studies of plitidepsin are warranted, and our results suggest that plitidepsin could be appropriately developed in combination with other antitumour where myelosuppression is dose-limiting.