Food Effect on the Pharmacokinetics of VC004, a Tropomyosin Receptor Kinase Inhibitor: A Randomized Crossover Trial in Healthy Chinese Subjects.

BACKGROUND AND OBJECTIVE: VC004 is a novel next-generation tropomyosin receptor kinase (TRK) inhibitor that is approved for the treatment of advanced or metastatic NTRK fusion-positive solid tumors and abrogated the drug resistance of the first-generation TRK inhibitors. The objective of the present study was to evaluate the effect of food on the pharmacokinetics and safety of VC004. METHODS: The study was a randomized, open-label, two-period crossover, single-dose, phase I clinical trial. A total of 16 healthy subjects participated the trial. Subjects fasted for 10 h before drug administration in both fasting and fed states. Subjects received VC004 50 mg orally in the fasting state and after a high caloric food in the fed state. Blood samples at the designated time points were collected to determine the plasma concentration of VC004. Safety evaluation in both the fasted and fed periods were assessed via vital sign monitoring and clinical laboratory tests. RESULTS: The maximum plasma concentration (Cmax) of VC004 in fed group decreased by 32.8%, corresponding with the slower absorption rate (time to Cmax (Tmax) delayed by almost 3 h) compared with the fasting group. Ratios of geometric means (GMRs) and 90% confidence intervals (90% CIs) of Cmax, the area under the curve of plasma concentration-time from zero to the last measurable concentration (AUC0-t), and AUC from zero to infinity (AUC0-∞) for VC004 between the two states were 67.18 (58.16-77.60), 103.59 (95.04-112.92) and 103.55 (95.63-112.11), respectively. No serious adverse events (AEs) occurred; only three grade 1 or grade 2 adverse events occurred in the fasted group, who recovered by the end of the study. CONCLUSIONS: The intake of high calorie food decreased the absorption rate and increased the Tmax of VC004, while the AUC values were similar in both groups. No serious adverse event was reported. In conclusion, food does not alter the pharmacokinetics and safety profile of VC004 in a clinically meaningful manner. TRIAL REGISTRATION: ClinicalTrials.gov ID: NCT055528120.

Effect of a moderate CYP3A inducer efavirenz on the pharmacokinetics of fuzuloparib: An open-label, fixed sequence study in Chinese healthy male subjects.

To evaluate the potential drug-drug interaction (DDI), safety and tolerability of fuzuloparib co-administered with a moderate CYP3A inducer efavirenz in healthy male subjects. Eighteen healthy male subjects were enrolled in a single-center, single-arm, open-label, fixed-sequence study. Fuzuloparib was administered as a single oral 50 mg under a fasting state on day 1, efavirenz (600 mg once daily) was given on days 4-17 before bed time, concomitantly with fuzuloparib on day 18, and for the follow-up 3 additional days (days 19-20). Pharmacokinetic sampling was performed following each fuzuloparib dose. Safety and tolerability were assessed during the whole process via clinical laboratory tests. Ratios of least-squares means (GMRs) and 90% geometric confidence interval (90% CI) of maximum plasma concentration (Cmax), the area under the curve of plasma concentration-time from zero to the last measurable concentration (AUC0 - t) and the area under the curve of blood concentration from zero to infinity (AUC0-∞) for fuzuloparib combined with efavirenz to fuzuloparib alone were 0.473 (0.394, 0.568), 0.220 (0.185, 0.263) and 0.221 (0.185, 0.263), respectively. Co-administration with efavirenz led to 53% and 78% decreases in fuzuloparib Cmax and AUC0-∞. All 18 subjects enrolled in this study were included in the safety analysis set. A total of 16 subjects had 62 AEs during the study period. No serious adverse events (SAE) were reported. Most treatment-emergent adverse events were grade 1 or 2 based on CTCAE. Only one grade 3 adverse event was observed. Concomitant intake of fuzuloparib with the moderate CYP3A inhibitor efavirenz resulted in a decrease in fuzuloparib AUC0-∞ and Cmax of 78% and 53% respectively. The results suggested that concomitant moderate CYP3A inducers should be avoided during the administration of fuzuloparib, or else the dosage adjustments should be required. (This trial was registered at http://www.chinadrugtrials.org.cn . The registration No. is CTR20211022, and the date of registration is 2021-05-13).

Phase I study to evaluate of the gastric pH-dependent drug interaction between famitinib and the proton pump inhibitor omeprazole in healthy subjects.

To evaluate the potential gastric pH-dependent drug-drug interaction (DDI), safety and tolerability of famitinib co-administered with omeprazole in healthy subjects. Twenty healthy subjects were enrolled in a single-center, single-arm, open-label, fixed-sequence study. Famitinib was administered as a single oral 25 mg under a fasting condition on day 1, omeprazole (40 mg once daily) was given on days 10-14, concomitantly with famitinib on day 15, and for the follow-up 7 additional days (days 16-22). Blood samples were collected for the pharmacokinetic analysis of famitinib and its metabolite SHR116637 following each famitinib dose. Safety and tolerability were assessed during the whole progress via clinical laboratory tests. The least-squares geometric mean ratios (GMRs) (90% CI) of Cmax, AUC0-t and AUC0-∞ for famitinib combined with omeprazole to famitinib alone were 0.989 (0.953, 1.027), 0.956 (0.907, 1.007) and 0.953(0.905, 1.005) respectively. For the metabolite SHR116637, their GMRs (90% CI) of the above parameters were 0.851 (0.786, 0.920), 0.890 (0.838, 0.946)and 0.887 (0.835, 0.943), indicating the absence of significant differences in the parameters. During the treatment period, 9(45%) subjects reported 16 treatment emergent adverse events (TEAE), among which 6 subjects (30%) reported 9 TEAEs and 1 subject (5%) reported 1 TEAE during famitinib or omeprazole administered alone respectively, 5 subjects (25.0%) reported 6 TEAEs during in the combined administration phase. Omeprazole did not have a significant influence on the pharmacokinetics (PK) of famitinib and SHR116637, and the safety profile was good upon co-administration. ClinicalTrials.gov identifier NCT 05,041,920.

Effects of rifampicin on antineoplastic drug pyrotinib maleate pharmacokinetics in healthy subjects.

PURPOSE: Pyrotinib (PTN), an irreversible EGFR/HER2 dual tyrosine kinase inhibitor used for treating HER2-positive breast cancer, is primarily metabolized by cytochrome P450 (CYP)3A4 isozyme. Rifampicin (RIF) is a strong index CYP3A4 inducer. Therefore, the study aimed to elucidate the effect of RIF on PTN pharmacokinetics (PK) in Chinese healthy volunteers. METHODS: This phase I, open-label study investigated the effects of steady-state RIF administration on single-dose PK of PTN. 18 healthy participants were enrolled in this trial, who received a single oral dose of 400 mg of PTN on days 1 and 13, and were administrated with RIF 600 mg qd on days 6 through 16. RIF was administrated on an empty stomach, PTN were administrated orally in the morning 30 min after the start of the standard meal. Serial PK samples for PTN were collected on days 1 and days 13. Safety assessments were performed via clinical laboratory tests throughout the study. RESULTS: 18 subjects were enrolled and 16 completed the study. RIF significantly reduced PTN exposure: Geometric least-squares mean ratios (90% CI) for PTN + RIF versus PTN alone were 0.04 (0.034,0.049), 0.04 (0.037,0.054), and 0.11 (0.09,0.124) for area under the curve from time zero to time of last quantifiable concentration (AUC0 - t), area under the curve from time zero to infinity (AUC0-∞ ), and maximum observed plasma concentration(Cmax), respectively. PTN alone and co-administered with RIF was well tolerated. CONCLUSION: The exposure of PTN was significantly affected by the action of RIF. The findings suggest that concomitant strong CYP3A4 inducers should be avoided during PTN treatment. Concurrent administration of PTN and RIF was well tolerated.

Mechanisms and pharmacokinetic/pharmacodynamic profiles underlying the low nephrotoxicity and ototoxicity of etimicin.

Etimicin (ETM), a fourth-generation aminoglycosides (AGs), is now widely clinically used in China due to its high efficacy and low toxicity. However, the mechanisms underlying its low nephrotoxicity and ototoxicity remain unclear. In the present study we compared the antibacterial and toxicity profiles of etimicin, gentamicin (GM, a second-generation AG), and amikacin (AMK, a third-generation AG), and investigated their pharmacokinetic properties in the toxicity target organs (kidney and inner ear) and subcellular compartments. We first demonstrated that ETM exhibited superior antibacterial activities against clinical isolates to GM and AMK, and it exerted minimal nephrotoxicity and ototoxicity in rats following multi-dose administration. Then, we conducted pharmacokinetic studies in rats, showed that the three AGs accumulated in the kidney and inner ear with ETM being distributed to a lesser degree in the two toxicity target organs as compared with GM and AMK high-dose groups. Furthermore, we conducted in vitro experiments in NRK-52E rat renal tubular epithelial cells and HEI-OC1 cochlear hair cells, and revealed that all the three AGs were distributed predominantly in the mitochondria with ETM showing minimal accumulation; they not only directly inhibited the activity of mitochondrial complexes IV and V but also inhibited mitochondrial function and its related PGC-1α-NRF1-TFAM pathway; ETM caused minimal damage to the mitochondrial complex and mitochondrial biogenesis. Our results demonstrate that the minimal otonephrotoxicity of ETM results from its lesser accumulation in mitochondria of target cells and subsequently lesser inhibition of mitochondrial function. These results provide a new strategy for discovering novel AGs with high efficacy and low toxicity.

Apatinib, a selective VEGFR2 inhibitor, improves the delivery of chemotherapeutic agents to tumors by normalizing tumor vessels in LoVo colon cancer xenograft mice.

Tumor vascular normalization has been proposed as a therapeutic strategy for malignant neoplasms, which can also interpret the synergistic effect of anti-angiogenesis agents combined with chemotherapy. Apatinib (Apa), a highly selective VEGFR2 inhibitor, attracts much attentions due to its encouraging anticancer activity, especially in the clinical trials of combined treatment. In this study, we investigated whether Apa could promote vascular normalization in tumor in a certain time window. Mice bearing LoVo colon cancer xenograft were orally administrated Apa (150 mg kg-1 per day) for 5, 7, 10, or 12 days. Apa significantly inhibited tumor growth and decreased the microvessel density. Using multi-photon microscopy and electron microscopy, we found that Apa improved tumor vessel morphology by pruning distorted vessel branches and decreased the gap between endothelial cells after a 7-day treatment. Furthermore, Apa decreased vessel leakage and increased pericyte coverage on vascular endothelial cells, suggesting that tumor vessels were more mature and integrated. The intratumoral distribution of adriamycin (ADR) in Apa group was improved from day 7 to 10 without change in plasma drug concentration. Tumor blood perfusion was also increased in this window, and the expression of hypoxia induced factor 1α was downregulated, suggesting the effect of Apa on alleviating tumor hypoxic micro-environment. In conclusion, Apa may improve the effective perfusion of tumor vessels and increase the intratumoral distribution of ADR in a certain time window via normalizing tumor vessels. This normalization window (7 to 10 days of treatment) may contribute to develop a regimen of combined medication in clinic use of Apa.

Development and validation of a sensitive LC-MS/MS method without derivatization/ion-pairing agents for etimicin quantification in rat plasma, internal ear and kidney.

Etimicin (ETM), which belongs to the newest generation of aminoglycosides (AGs), has been proven to not only maintain but also strengthen the advantages of former AGs with relatively less toxicity. Now, it is widely applied for the treatment of bacterial infections in the clinic. Nevertheless, nephrotoxicity and ototoxicity are unavoidable issues for AGs, and while ETM is no exception, the seriousness of these issues is different. To explore the reason why ETM exhibits less toxicity and to better direct the optimization and development of new AGs, it is of great necessity and importance to monitor the pharmacokinetic behaviors of ETM in its potential toxicity target organs, the kidney and internal ear, as well as in plasma. Therefore, a novel, sensitive and efficient LC-MS/MS method without derivatization or ion-pairing agents had been developed and validated for quantification of ETM in rat plasma, kidney and internal ear for the first time. This method showed good linearity over the range of 50-2000ng/mL for rat plasma/internal ear and 100-5000ng/mL for rat kidney. The precision was less than 4.4% and the accuracy was below 4.8%. Recovery and matrix effects were 71.3%-82.8% and 97.6%-108.5%, respectively. After intravenous administration of a single dose of ETM, plasma drug concentrations fit well with a two-compartmental model, and the AUC0-∞, t1/2α, t1/2ß, MRT and CL were 127.96±5.52µg*h/mL, 0.53±0.03h, 3.32±1.11h, 1.01±0.03h and 234.80±10.05mL/h/kg, respectively. Particularly, ETM showed a considerably long half-life in kidney and internal ear, up to 155.96±19.95h and 83.11±26.60h, respectively, which might contribute greatly to its toxicity.