FACILE AND SENSITIVE HPLC-UV METHOD FOR DETERMINATION OF NINTEDANIB IN RAT PLASMA

Objective: In this study, a facile and sensitive high-performance liquid chromatographic method for determination of nintedanib in rat plasma was developed and validated.Methods: After plasma protein was precipitated by addition of acetonitrile, the supernatant underwent centrifugation. An aliquot was then injected into a high-performance liquid chromatographic system with a Mightysil RP-18 GP II ODS column (250 × 3.0 mm, length by inner diameter, 5-μm particle size) maintained at 50 °C. A mobile phase mixture of 20 mmol phosphate buffer (pH 3.0) and acetonitrile (7:3, v/v) was used at a flow rate of 0.6 mL/min, with UV detection at a wavelength of 390 nm for isocratic separation and detection of nintedanib, its main metabolite (BIBF1202), and p-nitrophenol as an internal standard.Results: The quantitative range of nintedanib concentration in this method was 12.5–400 ng/ml, and the calibration curves were linear. The intra-and inter-day accuracy values (relative errors) were in the range of −3.65%–4.00% and −3.65%–3.64%, respectively. The intra-and inter-day precision values (relative standard deviations) were<5.9% and 8.36%, respectively. The method was successfully applied to a pharmacokinetic analysis of nintedanib in rats after intravenous administration.Conclusion: In this study, a rapid, sensitive, and simple HPLC-UV method for the quantitation of nintedanib in rat plasma was developed and validated. The method was shown to be accurate and precise and was successfully applied to a pharmacokinetic study

Efficient gene silencing in metastatic tumor by siRNA formulated in surface-modified nanoparticles

We have developed a nanoparticle (NP) formulation for systemically delivering siRNA into metastatic tumors. The NP, composed of nucleic acids, a polycationic peptide and cationic liposome, was prepared in a self-assembling process. The NP was then modified by PEG-lipid containing a targeting ligand, anisamide, and thus was decorated for targeting sigma receptor expressing B16F10 tumor. The activity of the targeted NP was compared with the naked NP (no PEGylation) and non-targeted NP (no ligand). The delivery efficiency of the targeted NP was 4-fold higher than the non-targeted NP and could be competed by excess free ligand. Luciferase siRNA was used to evaluate the gene silencing activity in the B16F10 cells, which were stably transduced with a luciferase gene, in a lung metastasis model. The gene silencing activity of the targeted NP was significantly higher than the other formulations and lasted for 4 days. While confocal microscopy showed the naked NP provided no tissue selectivity and non-targeted NP was ineffective for tumor uptake, the targeted NP effectively penetrated the lung metastasis, but not the liver. It resulted in 70-80% gene silencing in the metastasis model after a single i.v. injection (150 μg siRNA/kg). This effective formulation also showed very little immunotoxicity

Efficient Oncogene Silencing and Metastasis Inhibition via Systemic Delivery of siRNA

The selective delivery of small interfering RNA (siRNA) to metastatic tumors remains a challenging task. We have developed a nanoparticle (NP) formulation composed of siRNA, a carrier DNA, a polycationic peptide, and cationic liposomes. The NP was obtained by a self-assembling process, followed by surface modification with a polyethylene glycol (PEG)-conjugated ligand, anisamide. The NP was PEGylated and a ligand was presented to target sigma receptor–expressing murine melanoma cells, B16F10. The lung metastasis model was established by intravenous (IV) injection of the B16F10 cells into C57BL/6 mice. A mixture of siRNA against MDM2, c-myc, and vascular endothelial growth factor (VEGF) co-formulated in the targeted NP caused simultaneous silencing of each of the oncogenes in the metastatic nodules. Two consecutive IV injections of siRNA in the targeted NP significantly reduced the lung metastasis (~70–80%) at a relatively low dose (0.45 mg/kg), whereas free siRNA and the nontargeted NP showed little effect. This targeted NP formulation significantly prolonged the mean survival time of the animals by 30% as compared to the untreated controls. At the therapeutic dose, the targeted NP showed little local and systemic immunotoxicity and did not decrease the body weight or damage the major organs

Ingestibility and Formulation Quality of Lansoprazole Orally Disintegrating Tablets

Objectives. We evaluated the ingestibility and formulation quality of one branded (formulation A) and five generic (formulations B, C, D, E, and F) lansoprazole orally disintegrating (OD) tablets. Methods. Ingestibility, including the oral disintegrating time, taste, mouth feeling, and palatability, was examined by sensory testing in healthy subjects. Formulation qualities, including salivary stability, gastric acid resistance, and intestinal dissolution behavior, were examined. Results and Discussion. The oral disintegration time of formulation F (52 s) was significantly longer than that of other formulations (32-37 s). More than 90% of subjects did not experience bitterness with formulations A, E, and F, whereas 50% of subjects felt rough and powdery sensations with formulations B, C, and D. More than 80% of subjects suggested that formulations A, E, and F had good palatability. Ingestibility was different between formulations. OD tablets consist of enteric granules containing lansoprazole, which is unstable in gastric acid. Enteric granules of each formulation were stable in artificial saliva and gastric juice. No differences were observed in dissolution behaviors among the formulations, indicating that the formulation quality of the formulations was almost equivalent. Conclusions. This study provides useful information for selecting branded or generic lansoprazole OD tablets for individualized treatments

An efficient and low immunostimulatory nanoparticle formulation for systemic siRNA delivery to the tumor

We have developed a nanoparticle formulation [liposomes-protamine-hyaluronic acid nanoparticle (LPH-NP)] for systemically delivering siRNA into the tumor. The LPH-NP was prepared in a self-assembling process. Briefly, protamine and a mixture of siRNA and hyaluronic acid were mixed to prepare a negatively charged complex. Then, cationic liposomes were added to coat the complex with lipids via charge-charge interaction to prepare the LPH-NP. The LPH-NP was further modified by DSPE-PEG or DSPE-PEG-anisamide by the post-insertion method. Anisamide is a targeting ligand for the sigma receptor over-expressed in the B16F10 melanoma cells. The particle size, zeta potential and siRNA encapsulation efficiency of the formulation were approximately 115 nm, +25 mV and 90%, respectively. Luciferase siRNA was used to evaluate the gene silencing activity in the B16F10 cells, which were stably transduced with a luciferase gene. The targeted LPH-NP (PEGylated with ligand) silenced 80% of luciferase activity in the metastatic B16F10 tumor in the lung after a single i.v. injection (0.15 mg siRNA/kg). The targeted LPH-NP also showed very little immunotoxicity in a wide dose range (0.15 – 1.2 mg siRNA/kg), while the previously published formulation, LPD-NP (liposome-protamine-DNA nanoparticle), had a much narrow therapeutic window (0.15–0.45 mg/kg)