ABSTRACT
Since the impact of food on innovative drugs exposure will increase the risk of evaluation failures for safety and effectiveness, food effect study is routinely completed before multiple ascending dose (MAD) trials for innovative drugs. The prediction performance of physiologically-based pharmacokinetic absorption model (absorption PBPK model) in the application of food effect prediction has improved, we proposed a new strategy to explore food effect based on the absorption PBPK model. Based on the accurate prediction by absorption PBPK model, the food effect studies for qualified innovative drugs would be nested in MAD clinical trials to intend replacing the early independent food effect study. That would be promising to reduce costs and time for drug development, and also to provide the template for early food effect study in China.
ABSTRACT
Chloroquine (CQ) phosphate has been suggested to be clinically effective in the treatment of coronavirus disease 2019 (COVID-19). To develop a physiologically-based pharmacokinetic (PBPK) model for predicting tissue distribution of CQ and apply it to optimize dosage regimens, a PBPK model, with parameterization of drug distribution extrapolated from animal data, was developed to predict human tissue distribution of CQ. The physiological characteristics of time-dependent accumulation was mimicked through an active transport mechanism. Several dosing regimens were proposed based on PBPK simulation combined with known clinical exposure-response relationships. The model was also validated by clinical data from Chinese patients with COVID-19. The novel PBPK model allows in-depth description of the pharmacokinetics of CQ in several key organs (lung, heart, liver, and kidney), and was applied to design dosing strategies in patients with acute COVID-19 (Day 1: 750 mg BID, Days 2-5: 500 mg BID, CQ phosphate), patients with moderate COVID-19 (Day 1: 750 mg and 500 mg, Days 2-3: 500 mg BID, Days 4-5: 250 mg BID, CQ phosphate), and other vulnerable populations (.., renal and hepatic impairment and elderly patients, Days 1-5: 250 mg BID, CQ phosphate). A PBPK model of CQ was successfully developed to optimize dosage regimens for patients with COVID-19.
ABSTRACT
Objective To investigate radiation-induced alternations of phospholipids in epithelial cells,and to provide experimental evidence for understanding the mechanism of radiation-induced intestinal injury.Methods The intestinal epithelial cells(IEC-6)in rats were divided into three groups:normal control group,8 Gy X-ray irradiation group and 12 Gy X-ray irradiation group.Phospholipids were extracted at 6 h or 24 h after radiation and then measured by high-performance liquid chromatography and mass spectrometry(HPLC-MS).Results At 6 h after radiation,the phospholipids in 8 Gy irradiation group didn't vary significantly,while those in 12 Gy irradiation group changed.The PG,PI and Lyso PC were significantly up-regulated(F=5.37,9.60,9.88,P＜0.05).However,at 24 h after radiation,many PE and PG species in both irradiation groups declined(F=5.15-99.77,P＜0.05)and SM species increased in 12 Gy irradiation group(F=4.35-7.92,P＜0.05).Conclusions The ionizing radiation could disorder phospholipid metabolism in IEC-6 cells with a dose-dependent manner.