Tacrolimus Intrapatient Variability After Switching From Immediate or Prolonged-Release to Extended-Release Formulation, After an Organ Transplantation

Background and Purpose: Several formulations of tacrolimus are available, but evidence of the benefit of changing to the most recent formulations is lacking. Tacrolimus intra-patient variability (tacrolimus IPV) is an emerging risk factor associated with poor graft outcomes after solid organ transplantations. Here, we examined the modifications of tacrolimus IPV after switching to a different formulation of tacrolimus.Experimental Approach: We identified 353 solid organ transplant recipients that were switched in our center from immediate-release (IR-tacrolimus) or prolonged-release tacrolimus (PR-tacrolimus) to extended-release, LCP-tacrolimus (LCP-tacrolimus). Among them, 54 patients underwent at least 3 available tacrolimus blood concentrations before and after the switch, allowing us to investigate tacrolimus IPV.Key Results: The switch was considered as a safe procedure since only four of the 353 patients presented a graft rejection after the switch, and no patient was hospitalized for tacrolimus overdose. The tacrolimus IPV estimated by the coefficient of variation (CV-IPV) was stable before and after the switch to LCP-tacrolimus (CV-IPV: 29.0% (IQR 25–75 (15.5; 38.5) before and 24.0% (15.8; 36.5) after the switch, p = 0.65).Conclusion and Implications: Switching from IR- or PR-tacrolimus to LCP-tacrolimus is a safe procedure. However, the CV-tacrolimus IPV was not impacted by the change of formulation.

Simple Hplc Method Development for the Estimation of Galantamine Hydrobromide in Extended-Release Formulation

For the determination of Galantamine Hydrobromide in bulk and produced extended formulation, a new sensitive and quick HPLC technique was developed and validated according to ICH guidelines. The HPLC analysis was carried out using a waters system with a Thermo Scientific C18 (steel column (5 µm, 250mm × 4.6 mm)) column and a mobile phase of 0.1M phosphate buffer: Acetonitrile (40:60V/V) pH adjusted to 4.5 with orthophosphoric acid, at a flow rate of 1.0 mL/min. The detection was done at a wavelength of 203 nm, and galantamine hydrobromide had a retention time of 8.0 minutes. Over the concentration range of 1-10 g/ml, the calibration plot revealed a linear relationship. The accuracy of the proposed method was determined by recovery studies and was found to be near to 100 and % RSD value was found less than 2. The repeatability testing for both standard and sample solutions showed that the method is precise within the acceptable limits. RSD % of the determination of precision was <2%. The proposed method showed excellent linearity, accuracy, precision, specificity, robustness and system suitability results within the acceptance criteria. In addition, Saturation solubility of Galantamine Hydrobromide was determined in different pH mediums and it was found that Galantamine Hydrobromide has pH-dependent solubility, freely soluble in alkaline pH, and insoluble in acidic pH.

NIKKOMYCIN Z AGAINST DISSEMINATED COCCIDIOIDOMYCOSIS IN A MURINE MODEL OF SUSTAINED RELEASE DOSING

Introduction. Nikkomycin Z (nikZ) is a chitin synthase inhibitor. Efficacy against Coccidioides has been demonstrated in animal models of pulmonary or brain infection. Its short half-life, in mice and humans, would necessitate divided daily dosing. We assayed nikZ efficacy in disseminated coccidioidomycosis (in a reduction of CFU design), and whether sustained release might be useful. Methods. Mice were challenged intravenously, with low or high arthroconidial inocula. Fluconazole, clinically the most commonly used anti-coccidioidal drug, was compared (gavage) at high dose to a dose range of nikZ administered intraperitoneally or, to mimic sustained release, administered continuously in drinking water. Therapy was given for 5 days. Results. In vitro, both fluconazole and nikZ inhibited the isolate studied; nikZ was fungicidal. Oral nikZ therapy gave similar results to intraperitoneal nikZ, and sterilized infection in most animals after low inoculum challenge. In both challenges, oral nikZ produced greater reduction of CFU in organs (lung, liver, spleen) than fluconazole. Oral nikZ doses ≥200 mg/kg/day were particularly effective, in all organs, and were well tolerated. This efficacy occurred even though, after severe challenge, mice had reduced water intake, resulting in ingesting less than the desired dose, particularly initially after infection. Summary . This study shows, for the first time, efficacy of nikZ against disseminated coccidioidomycosis. Efficacy was shown after challenges producing different levels of severity of disease. This study also suggests the likely benefits of developing an extended release formulation, supplying continuous systemic concentrations of nikZ.

Where are we now? Emerging opportunities and challenges in the management of secondary hyperparathyroidism in patients with non-dialysis chronic kidney disease

Rising levels of parathyroid hormone (PTH) are common in patients with chronic kidney disease (CKD) not on dialysis and are associated with an elevated risk of morbidity (including progression to dialysis) and mortality. However, there are several challenges for the clinical management of secondary hyperparathyroidism (SHPT) in this population. While no recognised target level for PTH currently exists, it is accepted that patients with non-dialysis CKD should receive early and regular monitoring of PTH from CKD stage G3a. However, studies indicate that adherence to monitoring recommendations in non-dialysis CKD may be suboptimal. SHPT is linked to vitamin D [25(OH)D] insufficiency in non-dialysis CKD, and correction of low 25(OH)D levels is a recognised management approach. A second challenge is that target 25(OH)D levels are unclear in this population, with recent evidence suggesting that the level of 25(OH)D above which suppression of PTH progressively diminishes may be considerably higher than that recommended for the general population. Few therapeutic agents are licensed for use in non-dialysis CKD patients with SHPT and optimal management remains controversial. Novel approaches include the development of calcifediol in an extended-release formulation, which has been shown to increase 25(OH)D gradually and provide a physiologically-regulated increase in 1,25(OH)2D that can reliably lower PTH in CKD stage G3–G4 without clinically meaningful increases in serum calcium and phosphate levels. Additional studies would be beneficial to assess the comparative effects of available treatments, and to more clearly elucidate the overall benefits of lowering PTH in non-dialysis CKD, particularly in terms of hard clinical outcomes. Graphic abstract

COMPATIBILITY SCREENING OF VIDAGLIPTIN WITH IONIC AND NON-IONIC POLYMERIC EXCIPIENTS FOR THE DESIGN OF EXTENDED RELEASE DELIVERY SYSTEM

Studies of drug-polymer compatibility play an important role in the preformulation stage for the development of pharmaceutical dosage forms. The potential physical and chemical interactions between drugs and polymer can affect the chemical nature, stability and bioavailability of the dosage form and as a result in the therapeutic response in the clinical phase. The present study reveals the thermal and spectroscopic study of physical mixtures of Vildagliptin (VDG) and HPMC in combination with cationic polymers chitosan, anionic polymers NaCMC and nonionic polymers PEO for extended release (ER). In the first phase of the study, differential scanning calorimeter (DSC) was used as tool to detect any interaction. In the next phase, a Fourier Transform Infrared Spectroscopy (FT-IR) technique was used to confirm and to investigate the type of the possible interactions between the components. In both cases, the spectroscopic data revealed that the analysed polymeric excipients did not show any affect on the VDG. Results of the present study indicated the suitability of the HPMC K4M hydrophilic matrix polymers in combination with cationic polymers, anionic polymers and non-ionic polymers in the preparation of extended release formulation of VDG.

Potential Enhancement of Metformin Hydrochloride in Lipid Vesicles Targeting Therapeutic Efficacy in Diabetic Treatment

The potential enhancement of metformin hydrochloride (MH) loaded in lipid vesicles targeting therapeutic efficacy on alloxan-induced diabetic rats was investigated. This involved lipid vesicles formulated with homogenously distributed nano-sized particles by a novel integrated process of multiple emulsification by membrane and solvent evaporation. The average diameter of the water-in-oil (W1/O), W1/O/W2 emulsion droplets, and lipid vesicles was 192 nm, 52 µm, and 173 nm, respectively. The entrapment yield of metformin hydrochloride (MH) in the prepared lipid vesicles was 40.12%. The metformin hydrochloride-loaded lipid vesicles (MH-LLVs) sustained the release of the entrapped drug over a 12-h period and reduced the plasma glucose level of diabetic rats by 77.4% compared with free MH solution (2-h period and 58.2%, respectively) after one week post-diabetic treatment through oral administration of MH-LLV and the free drug. The remarkable improvement in the biochemical parameters recorded in the MH-LLV-treated animals compared with those that received free MH solutions depicted an enhanced kidney function, liver function, as well as oxidative stress status. Pancreatic histology depicted a pancreas with intralobular ducts (ID) and exocrine secretory acini that characterize an intact pancreas, which suggests the ability of the MH-LLVs to restore pancreatic cells to normal, on a continued treatment. Overall, MH-LLV appears an encouraging extended-release formulation with enhanced bioavailability, sustained release, and improved antihyperglycemic potentials.

PHARMACOKINETIC STUDY OF OLOPATADINE 10 MG EXTENDED RELEASE TABLET IN COMPARISON WITH OLOPATADINE 5 MG IMMEDIATE RELEASE TABLET IN INDIAN POPULATION

Objective: This study was designed to assess the pharmacokinetics of single dose of olopatadine hydrochloride 10 mg extended release (ER) tablet of Ranbaxy laboratories limited (two test formulations) with two doses of Allelock® 5 mg immediate release (IR) tablets of Kyowa Hakko Kogyo Co. Ltd. (reference formulation R), in healthy, adult, Indian male subjects under fed condition. Methods: Fifteen healthy male volunteers, 26.07±6.62 y in age and 57.17±6.68 kg in body weight, were divided into three groups and received either olopatadine hydrochloride 10 mg ER tablet or two doses of Allelock® 5 mg tablets in each period. Blood samples were taken at predetermined time points and plasma concentrations of olopatadine were monitored by liquid chromatography mass spectrometric (LCMS/MS). Pharmacokinetic (PK) parameters AUC0-t, AUC0-24, AUC0-∞, and Cmax were calculated for olopatadine using WinNonlin. A statistical analysis was performed on PK data using SAS system. Results: The ER formulations showed a similar AUC as compared to the IR formulation and there was no statistically significant difference in AUC of test formulation A and B and reference R. The ratios of AUC0-t, AUC0-24 and AUC0-∞ for A/R were 91.08, 94.90 and 91.32 and for B/R were 89.63, 93.95 and 89.63 respectively. The ER formulations reported a higher Cmax value as compared to IR formulation. The ratios of Cmax for A/R and B/R were 151.09 and 167.96 respectively. But these higher Cmax values did not pose any safety issue as there were no serious adverse events reported during the study. Conclusion: In conclusion, we can say that though the study drugs did not meet the bioequivalence criteria set by regulatory agencies, but this study gave an insight about PK properties of olopatadine extended release formulation and given an idea about effect of smoking on the PK profile of olopatadine which can be studied in future.