Effect of the Similarity of Formulations and Excipients of Approved Generic Drug Products on In Vivo Bioequivalence for Putative Biopharmaceutics Classification System Class III Drugs.

One of the potential essential factors that restricts generic industry from applying the Biopharmaceutics Classification System (BCS) Class III biowaiver is adherence to the stringent formulation criteria for formulation qualitative (Q1) sameness and quantitative (Q2) similarity. The present study has investigated formulations and excipients from 16 putative BCS Class III drug substances in a total of 19 drug products via 133 approved abbreviated new drug applications (ANDAs) containing in vivo bioequivalence (BE) studies in human subjects during the time period from 2006 to 2022. We included the BCS Class III drugs in this study by referring to published literature, the World Health Organization (WHO) BCS Class I-IV list, FDA internal assessments, and physicochemical properties (high solubility and low permeability) of specific drug substances. Based upon all 133 approved generic formulations in this study, the highest amount of each different compendial excipient with a total of 40 is defined as its corresponding typical amount that has not shown any potential impact on in vivo drug absorption. In the present study, although only 30.08% of the investigated generic formulations met Q1 the same/Q2 similar formulation criteria for the BCS Class III biowaiver, and while approximately 69.92% failed to meet those criteria with non-Q1/Q2 similar formulations, all test/reference ratios (T/R) and 90% confidence intervals for all instrumental PK parameters (AUC0-t, AUC0-inf, and Cmax) met the bioequivalence (BE) criteria (80-125%). The results of formulation assessment suggest that the commonly used excipients without atypical amounts did not impact absorption of 16 putative BCS Class III drug substances. The rate and extent of absorption of drugs appears to be more dependent upon the biopharmaceutic and physiochemical properties of BCS Class III drug substance and less, or not dependent upon their formulations, excipients, and the excipients class. Our findings may lead to a more flexible formulation design space regarding the stringent BCS Class III formulation criteria.

Social Exclusion and Depression among undergraduate students: the mediating roles of rejection sensitivity and social self-efficacy.

Nowadays, depression has been a prominent mental health problem throughout the world. A common but negative social experience, social exclusion (also known as ostracism) is a great risk factor for individuals' health and adaptation. Undergraduate students are in a development period of challenges and transitions, so they are vulnerable to suffering from depression and negative social experiences. Against this background, the present study aimed to examine the association between social exclusion and undergraduate students' depression as well as the underlying mechanism - the mediating roles of rejection sensitivity and social self-efficacy. Seven hundred sixty-two undergraduate students were recruited to participate in this study, who were asked to complete a set of questionnaires measuring social exclusion, depression, rejection sensitivity, and social self-efficacy. After controlling for gender, social exclusion was positively associated with undergraduate students' depression. And rejection sensitivity and social self-efficacy could significantly mediate this relation through three mediating paths - the separate mediating effects of rejection sensitivity and social self-efficacy, as well as the serial mediating effect of rejection sensitivity and social self-efficacy. These results could not only deepen our understanding of this theme, but also have several practical implications for the intervention of depression, for example, relevant social skill training and cognitive therapy could be adopted to intervene the rejection sensitivity and social self-efficacy.

A compartmentalized culture device for studying the axons of CNS neurons.

We report here the development of a compartmentalized culture device that allows the spatial separation of the somatodendrites and axons of central nervous system (CNS) neurons. The device consists of two compartments separated by a septum constructed by attaching a porous polycarbonate track etch (PCTE) filter on top of a microchannel-filled polydimethylsiloxane (PDMS) membrane. The surface and microchannels of the septum are coated and filled, respectively, with materials that support neuron growth and neurite migration. When rat hippocampal neurons are cultured in the top compartment, axons are the only processes that can migrate through the septum to the bottom compartment. The axons in the bottom compartment can be studied directly in real-time or through immunofluorescence staining after fixation. Axons containing ∼3 µg protein can be isolated from each device for biochemical analyses. In addition, the septum also impedes the movement of small molecules between the top and bottom compartments. This feature allows the somatodendrites and axons of neurons, which occupy the top and bottom compartments of the device, respectively, to be manipulated independently. The potential applications of the device as a tool in diverse studies concerning neuronal axons and in screening reagents that regulate axonal functions have also been discussed.

Nickel-catalyzed C-N bond reduction of aromatic and benzylic quaternary ammonium triflates.

A nickel-catalyzed, efficient C-N bond reduction of aromatic and benzylic ammonium triflates has been developed using sodium isopropoxide as a reducing agent. The high efficiency, mild conditions, and good compatibility with various substituents made this method an effective supplement to the current catalytic hydrogenation reactions. Combining this reductive deamination reaction with directed aromatic functionalization reactions, a powerful strategy for regioselective functionalization of arenes was demonstrated using dialkylamine groups as traceless directing groups.

[Pharmacokinetics of SN-38 in rats and tissue distribution of 7-ethyl-10-hydroxycamptothecin in mice after intravenous injection of irinotecan hydrochloride nanoparticles].

The paper reported an investigation of the pharmacokinetics of SN-38 (7-ethyl-10-hydroxy-camptothecin) in rats and the tissue distribution in mice after injection of irinotecan hydrochloride nanoparticles (CPT-11) via tail veins. An LC-MS/MS method was established to determine the concentrations of SN-38 in whole blood of rats and in different tissues of mice. The pharmacokinetics and tissue distribution of SN-38 were compared after the intravenous injection of CPT-11 NPs and CPT-11 solution. Compared with irinotecan solution, the elimination half-life of SN-38 was prolonged from 2.17 h to 2.67 h after the intravenous injection of CPT-11 NPs, but its AUC had little change. After the injection of CPT-11 NPs in mice, over time, the concentrations of CPT-11-metabolized SN-38 in CPT-11 NPs were significantly higher in the whole blood, colon and lungs than those in CPT-11 solution, followed by in the spleen and liver, but those in the heart and brain had no change. However, the amount of SN-38 in the kidneys was reduced with time. CPT-11 NPs could prolong SN-38's (one of its metabolites) blood circulation time in rats and significantly increased the concentration of CPT-11-metabolized SN-38 in the whole blood, colon and lungs of mice. CPT-11 NPs made SN-38 efficiently target-bind to the colon and lungs of mice.

[Pharmacokinetic interaction of pioglitazone hydrochloride and atorvastatin calcium in Beagle dogs].

The object of this study is to investigate the pharmacokinetic interaction of pioglitazone hydrochloride and atorvastatin calcium in healthy adult Beagle dogs following single and multiple oral dose administration. A randomized, cross-over study was conducted with nine healthy adult Beagle dogs assigned to three groups. Each group was arranged to take atorvastatin calcium (A), pioglitazone hydrochloride (B), atorvastatin calcium and pioglitazone hydrochloride (C) orally in the first period, to take B, C, A in the second period, and to take C, A, B in the third period for 6 days respectively. The blood samples were collected at the first and the sixth day after the administration, plasma drug concentrations were determined by LC-MS/MS, a one-week wash-out period was needed between each period. The pharmacokinetic parameters of drug combination group and the drug alone group were calculated by statistical moment method, calculation of C(max) and AUC(0-t) was done by using 90% confidence interval method of the bioequivalence and bioavailability degree module DAS 3.2.1 software statistics. Compared with the separate administration, the main pharmacokinetic parameters (C(max) and AUC(0-t)) of joint use of pioglitazone hydrochloride and atorvastatin calcium within 90% confidence intervals for bioequivalence statistics were unqualified, the mean t(max) with standard deviation used paired Wilcoxon test resulted P > 0.05. There was no significant difference within t1/2, CL(int), MRT, V/F. Pioglitazone hydrochloride and atorvastatin calcium had pharmacokinetic interaction in healthy adult Beagle dogs.

Multidrug release based on microneedle arrays filled with pH-responsive PLGA hollow microspheres.

This work presents an approach to codelivering transdermally two model drugs, Alexa 488 and Cy5, in sequence, based on a system of polyvinylpyrrolidone microneedles (PVP MNs) that contain pH-responsive poly(d,l-lactic-co-glycolic acid) hollow microspheres (PLGA HMs). The MN system provides the green fluorescence of Alexa 488 in PVP MNs, the red fluorescence of the DiI-labeled PLGA shell of HMs, and the cyan fluorescence of Cy5 in their aqueous core. Combined together, the prepared MN arrays support the localization of the HMs and the monitoring of the release profiles of model drugs within the skin tissues. The key component of this system is NaHCO(3), which can be easily incorporated into HMs. After HMs are treated with an acidic solution (simulating the skin pH environment), protons (H(+)) can rapidly diffuse through the free volume in the PLGA shells to react with NaHCO(3) and form a large number of CO(2) bubbles. This effect generates pressure inside the HMs and creates pores inside their PLGA shells, releasing the encapsulated Cy5. Test MNs were strong enough to be inserted into rat skin without breaking. The PVP MNs were significantly dissolved within minutes, and the first model drug Alexa 488, together with HMs, were successfully deposited into the tissues. Once in the acidic environment of the skin, the released HMs started to release Cy5 and continued to spread throughout the neighboring tissues, in a second step of the release of the drug. This approach can be used clinically to codeliver sequentially and transcutaneously a broad range of drugs.