Regulation of drug release performance using mixed doxorubicin-doxorubicin dimer nanoparticles as a pH-triggered drug self-delivery system

A mixed drug self-delivery system(DSDS)with high drug content(>50%)was developed to regulate pHtriggered drug release,based on two doxorubicin(DOX)-DOX dimmers:D-DOX_(ADH) and D-DOX_(car) conjugated with acid-labile dynamic covalent bonds(hydrazone and carbamate,respectively)and stabilized with PEGylated D-DOX_(ADH)(D-DOX_(ADH)-PEG).Owing to the different stability of the dynamic covalent bonds in the two dimers and the noncovalent interaction between them,pH-triggered drug release could be easily regulated by adjusting the feeding ratios of the two DOX-DOX dimers in the mixed DSDS.Similar in vitro cellular toxicity was achieved with the mixed DSDS nanoparticles prepared with different feeding ratios.The mixed DSDS nanoparticles had a similar DOX content and diameter but different drug releasing rates.The MTT assays revealed that a high anti-tumor efficacy could be achieved with the slowrelease mixed DSDS nanoparticles.

Integrating traditional Chinese (herbal) medicines into risk based regulation-With focus on non-clinical requirements to demonstrate safety

Within the public health sector of Hong Kong(China),there is a consensus around the important role of traditional Chinese medicines.For Hong Kong(China)to play a bridging role to bring Chinese medicines to the global market requires a concerted effort from the government,academic institutes and industries.The release of the final version of the European Medicines Agencies guidance document,which details the acceptance of minimum requirements to nonclinical package in bibliographical applications,grants the opportunity for well-established and traditional herbal medicines to demonstrate an‘acceptable safe’status for registration in the European Union.It is anticipated that this minimum nonclinical package can be applied to demonstrate the safe use of many traditional Chinese medicines regardless of their eligibility to be registered under the simplified procedure within the European Union.This paper conceptualizes an integration of a simplified evaluation route for eligible proprietary Chinese medicines(pCm)with long history of use into the existing drug regulatory framework in Hong Kong(China).Such integration utilizing the minimum nonclinical package,based on bibliographical data or expert report,as proof of evidence to demonstrate safety for pCm with long history of use requires less demand in scientific resources.With Hong Kong(China)conducting‘first hand’review for eligible pCm,it provides an option for overseas and local pharmaceutical companies to register their products in Hong Kong(China)without the need to rely on issuance of Certificate of Pharmaceutical Product from other countries.This could bring eligible pCm with long history of use to reach international risk-based standard and to be marketed globally as‘medicines’to reach their full therapeutic potential.An important process to positioning Hong Kong(China)to compete with other countries in promoting importation and exportation of pCm to better serve the global health.

Institutional changes of China's drug regulation and improvement solutions

Drug regulation is the most important policy to ensure drug safety.In this article,we analyzed institutional changes and problems in China＇s drug regulation.In addition,suggestions were provided to enhance the capacity of drug regulation,including a clearer functional positioning for drug regulation,increased resource inputs in drug regulation at central level,a more rational allocation of vertical drug regulatory functions,and an improved supervision mechanism for regulatory departments.

An overview of expedited approaches in China's drug review and approval regulation

Nowadays, CFDA has released a series of reform documents in drug registration review system, which may optimize the new drug evaluation model to accelerate the development of drugs. In this review, we summarized the qualifications and features of expedited approaches in drug review and approval in China, and compared these approaches with FDA. In conclusion, the expedited programs of drug approval in China have been gradually established and translated into policy benefits for drug makers and patients.