DEVELOPMENT AND VALIDATION OF A STABILITY-INDICATING RP-LC METHOD FOR THE DETERMINATION OF ANTICANCER DRUG EPIRUBICIN IN PHARMACEUTICALS

Development and Validation of Reversed-Phase HPLC Method for the Determination of Epirubicin and Its Application to the Pharmacokinetic Study of Epirubicin Loaded Polymeric Nanoparticle Formulations in Rats

Epirubicin, commonly used as anticancer drug for various types of tumors like breast, liver, lung, stomach, ovaries, and bladder for its improved antitumor efficacy and safety. A rapid, sensitive, and reliable bioanalytical method was developed and validated for epirubicin using conventional reverse phase HPLC with UV detection. The developed method was successfully applied to investigate the pharmacokinetics of epirubicin after intravenous administration of a reference epirubicin and its designed nano-formulations to rats. C18 column was used in an isocratic mode for analyte elution at a flow rate of 1.0 mL/min with UV detection of 234 nm. The mobile phase was composed of acetonitrile 22% (channel A) and 0.025% tri fluoro-acetic acid in water (channel B). Ondansetron was added as an internal standard, and the plasma samples were analyzed after protein precipitation. A concentration range of 0.016-1.024 μg/mL was selected for the construction of calibration curves, with LLOQ of 0.016 μg/mL. Results showed that the value of AUC, half-life, and mean residence time of designed nano-formulation were bounce to 10, 9, and 11 times higher, when compared to the reference epirubicin after intravenous dose of 10 mg/kg of epirubicin to rats, respectively. The designed epirubicin nano-formulations achieved clinically significant pharmacokinetic values in rats. Current method will help epirubicin future research using clinical samples and drug bioequivalence studies on various novel formulations for drug safety purposes.

In vitro compatibility and stability of admixtures containing etoposide, epirubicin hydrochloride and vindesine sulphate in a single infusion bag

WHAT IS KNOWN AND OBJECTIVES

The etoposide, doxorubicin hydrochloride, vincristine sulphate, cyclophosphamide and prednisone (EPOCH) chemotherapy regimen is effective in patients with relapsed or refractory non-Hodgkin's lymphoma. However, vincristine and doxorubicin hydrochloride are relatively toxic, leading to neurovirulence and cardiotoxicity, respectively. In this study, we replaced these drugs with vindesine and epirubicin hydrochloride to reduce the cardiotoxicity and evaluated admixtures containing these drugs along with etoposide in a single infusion bag in vitro.

METHODS

The appearance and pH of the admixtures were evaluated, and the number of particles was detected. High-performance liquid chromatography was used to measure the concentration and degradation rates of etoposide, epirubicin hydrochloride and vindesine sulphate in each admixture.

RESULTS AND DISCUSSION

No precipitation occurred when mixing clinically relevant concentrations of etoposide, epirubicin hydrochloride and vindesine sulphate in a 0.9% NaCl injection solution. Furthermore, the delta pH of the admixtures was ≤0.12 throughout the experiment, and the number of particles (≥10 and ≥25 μm) in the solutions over the 24 hours post-preparation period met USP standards. Etoposide, epirubicin hydrochloride and vindesine sulphate were retained at >96% of their initial concentrations in the admixtures at 25°C over the course of the experiment. Etoposide, epirubicin hydrochloride and vindesine sulphate are compatible when mixed in a 0.9% NaCl injection solution, and the admixtures are stable for at least 24 hours when stored in infusion bags.

WHAT IS NEW AND CONCLUSION

This in vitro analysis indicates the suitability of our novel admixtures containing less toxic drug equivalents in a single infusion bag for clinical application.

An eco-friendly stability-indicating spectrofluorimetric method for the determination of two anticancer stereoisomer drugs in their pharmaceutical preparations following micellar enhancement: Application to kinetic degradation studies

A new rapid and highly sensitive stability-indicating spectrofluorimetric method was developed for the determination of two stereoisomers anticancer drugs, doxorubicin (DOX) and epirubicin (EPI) in pure form and in pharmaceutical preparations. The fluorescence spectral behavior of DOX and EPI in a sodium dodecyl sulfate (SDS) micellar system was investigated. It was found that the fluorescence intensity of DOX and EPI in an aqueous solution of phosphate buffer pH4.0 and in the presence of SDS was greatly (about two fold) enhanced and the mechanism of fluorescence enhancement effect of SDS on DOX was also investigated. The fluorescence intensity of DOX or EPI was measured at 553nm after excitation at 497nm. The plots of fluorescence intensity versus concentration were rectilinear over a range of 0.03-2μg/mL for both DOX and EPI with good correlation coefficient (r>0.999). High sensitivity to DOX and EPI was attained using the proposed method with limits of detection of 10 and 9ng/mL and limits of quantitation of 29 and 28ng/mL, for DOX and EPI, respectively. The method was successfully applied for the determination of DOX and EPI in biological fluids and in their commercial pharmaceutical preparations and the results were concordant with those obtained using a previously reported method. The application of the proposed method was extended to stability studies of DOX following different forced degradation conditions (acidic, alkaline, oxidative and photolytic) according to ICH guidelines. Moreover, the kinetics of the alkaline and oxidative degradation of DOX was investigated and the apparent first-order rate constants and half-life times were calculated.

Identification of four new degradation products of epirubicin through forced degradation, LC-UV, MSn and LC-MS-TOF studies

Epirubicin (EPI) was subjected to International Conference on Harmonization recommended forced degradation under the conditions of hydrolysis, oxidation, dry heat and photolysis to characterize its possible impurities and/or degradation products. The drug was found highly unstable to alkaline hydrolysis even at room temperature, unstable to acid hydrolysis at 80°C and to oxidation at room temperature. The hydrolytic and oxidative degradation products were resolved on an Agilent RP8 (150 mm × 4.6 mm; 5 µm) column with isocratic elution using mobile phase composed of ammonium formate (10 mM, pH 3.0), acetonitrile and methanol. The drug degraded to four oxidative products (O-I, O-II, O-III and O-IV) and to one acid hydrolyzed product (A-I). Purity of each peak in liquid chromatography-ultraviolet (LC-UV) chromatogram was ascertained through photodiode array (LC-PDA) analysis. The products were characterized through electrospray ionization-mass spectrometry (+ESI-MS(n)) studies on EPI and liquid chromatography-time of flight mass spectrometry (LC-MS-TOF) studies on degraded drug solutions. The products, O-I-O-IV, were characterized as 2-hydroxy-8-desacetylepirubicin-8-hydroperoxide, 4-hydroxy-8-desacetylepirubicin-8-hydroperoxide, 8-desacetylepirubicin-8-hydroperoxide and 8-desacetylepirubicin, respectively, and product A-I was characterized as deglucosaminylepirubicin. While A-I was found to be a pharmacopoeial impurity, all oxidative products were found to be new degradation impurities. The mechanisms and pathways of degradation of EPI were discussed and outlined.