Caelyx (TM) in malignant mesothelioma: A phase II EORTC study

Background: The use of doxorubicin has shown some activity in malignant mes othelioma but prolonged administration is hampered by cardiotoxicity. Caely x(TM), a new liposomal and pegylated form of doxorubicin has shown a better pharmacokinetic and toxic profile then doxorubicin. In a phase II study, t he efficacy and toxicity of Caelyx(TM) was tested in previously untreated p atients with malignant pleural mesothelioma. Patients and methods: Thirty-three patients who had measurable or evaluable histologically confirmed malignant pleural mesothelioma were included in t he study. Caelyx(TM) (45 mg/m(2)) was given i.v. on outpatient base every f our weeks for nine cycles or till progression or unacceptable toxicity occu rred. Results: Of the 33 patients, 32 were evaluable for toxicity and 31 for resp onse. Two patients had a partial response (6%, 95% confidence interval: 0.2 %-20.2%). The median survival was 13 months. Forty percent of the patients received > 6 cycles. Toxicity was mild with palmar plantar erythrodysesthes ia being most pronounced (62% grade 1-2, 6% grade 3) and of limited duratio n. Ten percent of patients had grade 3 anemia and 3% grade 3 thrombocytopen ia. Two patients (6%) had grade 3 or 4 cardiac toxicity, which was not drug related. Conclusion: At the prescribed dose, single agent Caelyx(TM) is well tolerat ed but its activity in chemotherapy-naive mesothelioma patients does not wa rrant further investigation as a single agent.