Conflicting meal recommendations for oral oncology drugs: pose risks to patient care?

Pooled Analysis of Gastric Emptying in Patients With Obesity: Implications for Oral Absorption Projection

PURPOSE

Gastric emptying time is one of limiting factors that determines the pharmacokinetic properties of drugs administered by mouth. Despite the high prevalence of obesity worldwide, modifications in gastric emptying time have not been systematically addressed in this set of patients. The current analysis aims to quantitatively address obesity-related changes in gastric emptying time of solids, semisolids, and liquids compared with lean individuals, highlighting the relevant pharmacokinetic implications of oral drug absorption in patients with obesity.

METHODS

We searched the Cochrane Library, PubMed, Web of Science, and Embase for all relevant articles published until November 1, 2020. Differences in gastrointestinal variables in relation to gastric emptying between obese and lean individuals were quantified by weighted mean difference (WMD) and ratio of means (RoM). Robustness of the analyses was evaluated by subgroup analysis and publication bias test.

FINDINGS

A total of 17 studies with 906 participants were included. The gastric half-emptying time of solids (WMD, -10.4 minutes; P = 0.001; RoM, 0.90; P = 0.01) and liquids (WMD, -6.14 minutes; P < 0.001; RoM, 0.83, P = 0.03) was significantly shorter in individuals with obesity compared with lean individuals. These findings were confirmed by the subgroup analyses and publication bias tests.

IMPLICATIONS

Our pooled analysis systemically quantifies the differences in gastric half-emptying time between individuals with obesity and lean individuals, facilitating better understanding and prediction of drug absorption in individuals with obesity through physiologically based pharmacokinetic approaches. Obesity is associated with a faster transit of both solids and liquids through the stomach.

Effect of food on the pharmacokinetics of the WEE1 inhibitor adavosertib (AZD1775) in patients with advanced solid tumors

PURPOSE

To support future dosing recommendations, the effect of food on the pharmacokinetics of adavosertib, a first-in-class, small-molecule reversible inhibitor of WEE1 kinase, was assessed in patients with advanced solid tumors.

METHODS

In this Phase I, open-label, randomized, two-period, two-sequence crossover study, the pharmacokinetics of a single 300 mg adavosertib dose were investigated in fed versus fasted states.

RESULTS

Compared with the fasted state, a high-fat, high-calorie meal (fed state) decreased adavosertib maximum plasma concentration (Cmax) by 16% and systemic exposure (area under the plasma concentration-time curve [AUC]) by 6%; AUC0-t decreased by 7% and time to maximum plasma concentration was delayed by 1.97 h (P = 0.0009). The 90% confidence interval of the geometric least-squares mean treatment ratio for AUC and AUC0-t was contained within the no-effect limits (0.8-1.25), while that of Cmax crossed the lower bound of the no-effect limits. Adverse events (AEs) related to adavosertib treatment were reported by 20 (64.5%) of the 31 patients treated in this study. Grade ≥ 3 AEs were reported by four (12.9%) patients (one in the fed state, three in the fasted state); two of these AEs were considered treatment-related by the investigator. Three serious AEs were reported in three (9.7%) patients; these were not considered treatment-related. No patients discontinued because of treatment-related AEs, and no new safety signals were reported.

CONCLUSION

A high-fat meal did not have a clinically relevant effect on the systemic exposure of adavosertib, suggesting that adavosertib can be administered without regard to meals.

Gastric-acid-mediated drug-drug interactions with direct-acting antiviral medications for hepatitis C virus infection: clinical relevance and mitigation strategies

Drug-drug interactions (DDIs) between direct-acting antiviral (DAA) medications and acid-reducing agents mediated by gastric acid represent an important issue in drug development and treatment, which could lead to impaired bioavailability and subtherapeutic plasma concentrations of DAA drugs and subsequently compromised treatment outcomes. However, identification of clinically relevant drug interactions associated with elevated gastric pH is not well characterized. Here, we present the first comprehensive analysis of the gastric-acid-mediated drug interactions with all novel DAA medications by analyzing and revisiting in vitro data, prospective DDI trials and retrospective assessments based upon Phase II and III studies, aiming toward an in-depth understanding of the clinical implications and mitigation strategies to circumvent such interactions.