PurposeTo investigate the feasibility, pharmacokinetics, efficacy and toxicity of intrapleural paclitaxel liposome injection in non-small cell lung cancer (NSCLC) patients with malignant pleural effusions. Patients and methodsTwelve of 15 NSCLC patients with malignant pleural effusions were treated with paclitaxel liposome and three were treated with free paclitaxel. Adequate pleural fluid, blood and urine were collected for pharmacokinetic study. The clinical efficacy and toxicity were synthetically evaluated according to the correlative criteria. ResultsThe overall toxicity of paclitaxel liposome was lower than that of free paclitaxel. In the patients treated with paclitaxel liposome, there were minimal local chest pain, anaphylaxis, anaemia, neutropaenia and hepatotoxicity. The complete response rates of pleural effusion at the first, second, third and sixth month were, respectively, 27.3%, 18.2%, 9.1% and 9.1%, and overall response rates were 90.9%, 72.7%, 63.6% and 54.5%, respectively. Pharmacokinetic study showed that mean Cmax,IP, T1/2 and AUC0→96,IP in pleural fluid were, respectively, about 2-fold, 2-fold and 2.5-fold than those of free paclitaxel, and AUC0→96,Pla in plasma was also much higher than that of free paclitaxel, however, excretory rate in 24h from urine was lower than that of free paclitaxel. ConclusionsThis study demonstrated that paclitaxel liposome was a more useful agent than free paclitaxel for the treatment of malignant pleural effusions because of its relatively low toxicity and distinct pharmacokinetic characteristics. The phase II study of a large number of patients was recommended to confirm this finding.