Development and validation of stability indicating method for determination of sertraline following ICH guidlines and its determination in pharmaceuticals and biological fluids

<p>Abstract</p> <p>Background</p> <p>Sertraline is a well known antidepressant drug which belongs to a class called selective serotonin reuptake inhibitor. Most published methods do not enable studying the stability of this drug in different stress conditions.</p> <p>Results</p> <p>Two new methods were developed for the determination of sertraline (SER). Both methods are based on coupling with 4-chloro-7-nitrobenzo-2-oxa-1,3-diazole (NBD-Cl) in borate buffer of pH 7.8 and measuring the reaction product spectrophotometrically at 395 nm (Method I) or spectrofluorimetrically at 530 nm upon excitation at 480 nm (Method II). The response-concentration plots were rectilinear over the range 2-24 μg/mL and 0.25-5 μg/mL for methods I and II respectively with LOD of 0.18 μg/mL and 0.07 μg/mL, and LOQ of 0.56 μg/mL and 0.21 μg/mL for methods I and II, respectively.</p> <p>Conclusion</p> <p>Both methods were applied to the analysis of commercial tablets and the results were in good agreement with those obtained using a reference method. The fluorimetric method was further applied to the in vivo determination of SER in human plasma. A proposal of the reaction pathway was presented. The spectrophotometric method was extended to stability study of SER. The drug was exposed to alkaline, acidic, oxidative and photolytic degradation according to ICH guidelines. Moreover, the method was utilized to investigate the kinetics of oxidative degradation of the drug. The apparent first order rate constant and t_1/2of the degradation reaction were determined.</p

Characterization of Rhodamine-123 as a Tracer Dye for Use In In vitro Drug Transport Assays

Fluorescent tracer dyes represent an important class of sub-cellular probes and allow the examination of cellular processes in real-time with minimal impact upon these processes. Such tracer dyes are becoming increasingly used for the examination of membrane transport processes, as they are easy-to-use, cost effective probe substrates for a number of membrane protein transporters. Rhodamine 123, a member of the rhodamine family of flurone dyes, has been used to examine membrane transport by the ABCB1 gene product, MDR1. MDR1 is viewed as the archetypal drug transport protein, and is able to efflux a large number of clinically relevant drugs. In addition, ectopic activity of MDR1 has been associated with the development of multiple drug resistance phenotype, which results in a poor patient response to therapeutic intervention. It is thus important to be able to examine the potential for novel compounds to be MDR1 substrates. Given the increasing use rhodamine 123 as a tracer dye for MDR1, a full characterisation of its spectral properties in a range of in vitro assay-relevant media is warranted. Herein, we determine λmax for excitation and emission or rhodamine 123 and its metabolite rhodamine 110 in commonly used solvents and extraction buffers, demonstrating that fluorescence is highly dependent on the chemical environment: Optimal parameters are 1% (v/v) methanol in HBSS, with λex = 505 nm, λem = 525 nm. We characterise the uptake of rhodamine 123 into cells, via both passive and active processes, and demonstrate that this occurs primarily through OATP1A2-mediated facilitated transport at concentrations below 2 µM, and via micelle-mediated passive diffusion above this. Finally, we quantify the intracellular sequestration and metabolism of rhodamine 123, demonstrating that these are both cell line-dependent factors that may influence the interpretation of transport assays

Subcutaneous versus intravenous daratumumab in patients with relapsed or refractory multiple myeloma (COLUMBA): a multicentre, open-label, non-inferiority, randomised, phase 3 trial

Background: Intravenous daratumumab for treatment of patients with multiple myeloma involves a lengthy infusion that affects quality of life, and infusion-related reactions are common. Subcutaneous daratumumab is thought to be easier to administer and to cause fewer administration-related reactions. In this study (COLUMBA), we tested the non-inferiority of subcutaneous daratumumab to intravenous daratumumab. Methods: In this ongoing, multicentre (147 sites in 18 countries), open-label, non-inferiority, randomised, phase 3 trial, we recruited adult patients (age 6518 years) if they had confirmed relapsed or refractory multiple myeloma according to International Myeloma Working Group criteria; received at least three previous lines of therapy, including a proteasome inhibitor and immunomodulatory drug, or were double refractory to both a proteasome inhibitor and immunomodulatory drug; and had an Eastern Cooperative Oncology Group performance status score of 2 or lower. Patients were randomly assigned (1:1) by a computer-generated randomisation schedule and balanced using randomly permuted blocks to receive daratumumab subcutaneously (subcutaneous group) or intravenously (intravenous group). Randomisation was stratified on the basis of baseline bodyweight ( 6465 kg, 66\u201385 kg, &gt;85 kg), previous therapy lines ( 64four vs &gt;four), and myeloma type (IgG vs non-IgG). Patients received 1800 mg of subcutaneous daratumumab co-formulated with 2000 U/mL recombinant human hyaluronidase PH20 or 16 mg/kg of intravenous daratumumab once weekly (cycles 1\u20132), every 2 weeks (cycles 3\u20136), and every 4 weeks thereafter (28-day cycles) until progressive disease or toxicity. The co-primary endpoints were overall response and maximum trough concentration (Ctrough; cycle 3, day 1 pre-dose). The non-inferiority margin for overall response was defined using a 60% retention of the lower bound (20\ub78%) of the 95% CI of the SIRIUS trial. Efficacy analyses were done by intention-to-treat population. The pharmacokinetic-evaluable population included all patients who received all eight weekly daratumumab doses in cycles 1 and 2 and provided a pre-dose pharmacokinetics blood sample on day 1 of cycle 3. The safety population included all patients who received at least one daratumumab dose. This trial is registered with ClinicalTrials.gov, NCT03277105. Findings: Between Oct 31, 2017, and Dec 27, 2018, 655 patients were screened, of whom 522 were recruited and randomly assigned (subcutaneous group n=263; intravenous group n=259). Three patients in the subcutaneous group and one in the intravenous group did not receive treatment and were not evaluable for safety. At a median follow-up of 7\ub75 months (IQR 6\ub75\u20139\ub73), overall response and Ctrough met the predefined non-inferiority criteria. An overall response was seen in 108 (41%) of 263 patients in the subcutaneous group and 96 (37%) of 259 in the intravenous group (relative risk 1\ub711, 95% CI 0\ub789\u20131\ub737). The geometric means ratio for Ctrough was 107\ub793% (90% CI 95\ub774\u2013121\ub767), and the maximum Ctrough was 593 \u3bcg/mL (SD 306) in the subcutaneous group and 522 \u3bcg/mL (226) in the intravenous group. The most common grade 3 and 4 adverse events were anaemia (34 [13%] of 260 patients evaluable for safety in the subcutaneous group and 36 [14%] of 258 patients in the intravenous group), neutropenia (34 [13%] and 20 [8%]), and thrombocytopenia (36 [14%] and 35 [14%]). Pneumonia was the only serious adverse event in more than 2% of patients (seven [3%] in the subcutaneous group and 11 [4%] in the intravenous group). There was one death resulting from a treatment-related adverse event in the subcutaneous daratumumab group (febrile neutropenia) and four in the intravenous group (sepsis [n=2], hepatitis B reactivation [n=1], and Pneumocystis jirovecii pneumonia [n=1]). Interpretation: Subcutaneous daratumumab was non-inferior to intravenous daratumumab in terms of efficacy and pharmacokinetics and had an improved safety profile in patients with relapsed or refractory multiple myeloma. These data could contribute to the approval of the subcutaneous daratumumab formulation by regulatory bodies. Funding: Janssen Research &amp; Development