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Purpose: To speed the review and approval of drugs and address pressing medical needs, China began to advocate for the implementation of the conditional approval process in 2017. We aimed to assess the implementation of the conditional approval process in China and further analyze its potential problems and future challenges., Methods: This study examined the new drug approval with conditions in China between 2018 and 2021, based on an analysis of drug technical review documents from the Center for Drug Evaluation (CDE). Using publicly available information, we further analyzed the characteristics and results of pivotal clinical trials of conditionally approved drugs, postmarketing study requirements and progress., Findings: Between 2018 and 2021, China conditionally approved 50 drugs, with 80% (40/50) being antineoplastic agents. Premarketing pivotal trials predominantly used single-arm clinical trials (83.7%, 41/49), while postmarketing trials mainly employed randomized controlled clinical trials (81.0%, 34/42). In oncology drugs, conditionally approved drugs with progression-free survival (PFS) and overall survival (OS) as primary endpoints achieved significant clinical value in terms of efficacy. However, there were also pivotal clinical trials with response rate (RR) as the primary endpoint that demonstrated lower clinical benefits (8.9% of drugs with RR below 20%). Safety analysis revealed substantial variations in the proportions of grade ≥3 adverse events (AEs) and serious adverse events (SAEs) across pivotal trials (Grade ≥ 3 AEs: 9.0%-99.0%; SAEs: 8.0%-83.0%). For nononcology drugs, pivotal trials also demonstrated an acceptable risk-benefit ratio but exhibited methodological issues. Meanwhile, Most postmarketing studies lacked completion date restrictions (43.2%, 17/47), and no requirements were specified for the transition to full approval. Furthermore, surrogate endpoints were primarily utilized both pre- and postmarketing, but the rational selection of surrogate endpoints remains to be investigated., Implications: The conditional approval process expedites patient access to drugs for serious diseases. However, challenges pertaining to evidence assessment during approval and design flaws in postmarketing studies exist in China's conditional approval system, necessitating future improvements., Competing Interests: Declaration of Competing Interest The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (Copyright © 2023 Elsevier Inc. All rights reserved.)

Two electrochemical signals ascribed to xanthine/guanine and hypanthine/adenine in MCF-7 cells were detected at 0.726 and 1.053 V, respectively. Based on the intensity of signals, the genistein-induced proliferation and suppression of MCF-7 cells could be evaluated. The results showed that with the increase of genistein dose at the range of 10(-9) to 10(-6)M, the two electrochemical signals of MCF-7 cell suspension increased due to the proliferation, whereas the tendency at the high dosage range of more than 10(-5)M was decreased. The proliferation and cytotoxicity obtained by the electrochemical method were in agreement with those obtained by cell counting and the MTT [3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium] method. Thus, the two-signal electrochemical method is an effective way to evaluate the effect of drugs on cell activity based on purine metabolism., (Copyright © 2014 Elsevier Inc. All rights reserved.)

An in situ electrochemical method of cell viability, which integrated cell culture, pretreatment and detection in a cell culture dish, was developed. The method significantly improved the electrochemical response of cells, simplified the operation process, reduced the experiment time, avoided the use of trypsin, and was applied in the study of the effectiveness of antitumor drugs on tumor suppression. [ABSTRACT FROM AUTHOR]

Abstract: DNA G-quadruplex is an attractive drug target for anticancer therapy. Most G-quadruplex ligands have little selectivity, due to π-stacking interaction with common G-tetrads surface. Thanks to the varieties of G-quadruplex grooves, the groove-binding ligand is expected to create high selectivity. Therefore, developing novel molecular geometries that target G-quadruplex groove has been paid growing attention. In this work, steroid FG, a special nonplanar and nonaromatic small molecule, interacting with different conformations of G-quadruplexes has been studied by molecular docking and molecular dynamics simulations. The results showed the selectivity of the hydrophobic group of steroid FG for the wide groove of antiparallel G-quadruplex. The methyl groups on the tetracyclic ring of steroid represent the specific binding ability for the small hydrophobic cavity formed by reversed stacking of G-tetrads in antiparallel G-quadruplex groove. This work provides new insight for developing new classes of G-quadruplex groove-binding ligands. [Copyright &y& Elsevier]

An in situ electrochemical method was used to assess the cytotoxicity of chlorophenols using human breast cancer (MCF-7) and cervical carcinoma (HeLa) cells as models. On treatment with different chlorophenols, the electrochemical responses of the selected cells, resulting from the oxidation of guanine and xanthine in the cytoplasm, indicated the cell viability. In addition, the in situ in vitro electrochemical method was further compared with the traditional MTT (3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide) assays. Although similar cytotoxicity data were obtained from both methods, the effective concentrations of chlorophenols that inhibited 50% cell growth (EC 50 values) from the electrochemical method were only slightly lower than those from the MTT assay. These results indicate that the in situ in vitro electrochemical method paves a simple, rapid, strongly responsive, and label-free way to the cytotoxicity assessment of different chlorophenol pollutants. [ABSTRACT FROM AUTHOR]