Co-encapsulation of docetaxel and cyclosporin A into SNEDDS to promote oral cancer chemotherapy.

Self-nanoemulsifying drug delivery system (SNEDDS) have been considered as a promising platform for oral delivery of many BCS (biopharmaceutics classification system) class IV drugs, such as docetaxel (DTX). However, oral chemotherapy with DTX is also restricted by its active P-glycoprotein (P-gp) efflux and hepatic first-pass metabolism. To address these challenges, we developed a novel SNEDDS co-loaded with DTX and cyclosporine A (CsA) to achieve effective inhibition of P-gp efflux and P450 enzyme metabolization, improving oral bioavailability of DTX. The SNEDDS showed uniform droplet size of about 30 nm. Additionally, the prepared SNEDDS exhibited a sequential drug release trend of CsA prior to DTX. The intestinal experiments confirmed that the membrane permeability of DTX was significantly increased in the whole intestinal tract, especially in the jejunum segment. Furthermore, the oral bioavailability of co-loaded SNEDDS was 9.2-fold and 3.4-fold higher than DTX solution and DTX SNEDDS, respectively. More importantly, it exhibited a remarkable antitumor efficacy with a reduced toxicity compared with intravenously administered DTX solution. In summary, DTX-CsA co-loaded SNEDDS is a promising platform to facilitate oral docetaxel-based chemotherapy.

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.

PURPOSE: 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). METHODS: 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. RESULTS: 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. CONCLUSIONS: 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.

Formulating a single thioether-bridged oleate prodrug into a self-nanoemulsifying drug delivery system to facilitate oral absorption of docetaxel.

Oral chemotherapy of docetaxel (DTX) is restricted by active P-glycoprotein (P-gp) efflux, hepatic first-pass metabolism and then poor oral absorption. Herein, a lipophilic thioether-bridged oleate prodrug (DTX-S-OA) and an ester-bond linked oleate prodrug of docetaxel (DTX-OA) were synthesized and efficiently incorporated into a self-nanoemulsifying drug delivery system (SNEDDS) using core-matching technology with a high drug-loading rate. DTX-S-OA SNEDDS produced a uniform droplet size of about 30 nm and a significantly high drug loading capability (60 mg mL-1), compared with DTX SNEDDS (20 mg mL-1). Additionally, DTX-S-OA SNEDDS exhibited a markedly slower drug release property and higher (>2-fold) drug solubilization in the aqueous phase after 60 min lipolysis compared with DTX SNEDDS. In situ single-pass intestinal perfusion and intestinal biodistribution studies demonstrated that the membrane permeability and intestinal bioadhesion of SNEDDS were significantly increased. Moreover, DTX-S-OA showed a comparable ability with verapamil in inhibiting P-gp efflux. Lymphatic transport studies confirmed that DTX-S-OA SNEDDS could significantly enhance intestinal lymphatic transport. Notably, the bioavailability of DTX-S-OA SNEDDS was 6.2-fold and 2.0-fold higher than that of the DTX solution and DTX SNEDDS, respectively. Furthermore, DTX-S-OA achieved a more rapid release of free DTX from the prodrug in systemic circulation than DTX-OA. Therefore, such a unique combination strategy of the single thioether-bridged DTX-oleate prodrug and SNEDDS is a promising platform to enable effective oral delivery of DTX.

Integration of phospholipid-drug complex into self-nanoemulsifying drug delivery system to facilitate oral delivery of paclitaxel.

Self-nanoemulsifying drug delivery system (SNEDDS) has emerged as a promising platform to improve oral absorption of drugs with poor solubility and low permeability. However, large polarity molecules with insufficient lipid solubility, such as paclitaxel (PTX), would suffer from inferior formulation of SNEDDS due to poor compatibility. Herein, phospholipid-drug complex (PLDC) and SNEDDS were integrated into one system to facilitate oral delivery of PTX. First, PTX was formulated into PLDC in response to its inferior physicochemical properties. Then, the prepared PLDC was further formulated into SNEDDS by integrating these two drug delivery technologies into one system (PLDC-SNEDDS). After PLDC-SNEDDS dispersed in aqueous medium, nanoemulsion was formed immediately with an average particle size of ∼30 nm. Furthermore, the nanomulsion of PLDC-SNEDDS showed good colloidal stability in both HCl solution (0.1 mol/l, pH 1.0) and phosphate buffer solution (PBS, pH 6.8). In vivo, PTX-PLDC-SNEDDS showed distinct advantages in terms of oral absorption efficiency, with a 3.42-fold and 2.13-fold higher bioavailability than PTX-PLDC and PTX solution, respectively. Our results suggest that the integration of PLDC into SNEDDS could be utilized to facilitate the oral delivery of hydrophobic drugs with large polarity.

Chemotherapy agent-unsaturated fatty acid prodrugs and prodrug-nanoplatforms for cancer chemotherapy.

Unsaturated fatty acids (UFAs), with the distinct advantages of good biocompatibility and innate tumor-targeting effect, have been widely investigated for the rational design of chemotherapy agent-unsaturated fatty acid (CA-UFA) prodrugs in cancer therapy. Among them, several CA-UFA prodrugs have successfully entered clinical trials and are promising prospects for potential clinical applications. In addition, CA-UFA prodrug-based nanoparticulate drug delivery systems (nano-DDS), which integrate the advantages of CA-UFA prodrugs and nano-DDS, have been emerging as versatile nano-carriers for the efficient delivery of chemotherapeutics. In this paper, we review the advanced drug delivery strategies based on UFA conjugates and focus on the recent advances in CA-UFA prodrugs and the emerging CA-UFA prodrug-based nano-DDS. First, we discuss the rational design of CA-UFA prodrugs in response to the multiple obstacles in chemotherapy, with particular emphasis on the latest progress in both preclinical studies and clinical trials. Moreover, the emerging CA-UFA prodrug-based nano-DDS are also addressed. Finally, the prospects and potential challenges of CA-UFA prodrug-based drug delivery strategies in chemotherapy are highlighted.