Bioequivalence and food effect of a fixed-dose combination of macitentan and tadalafil: Adaptive design in the COVID-19 pandemic.

The COVID-19 pandemic has forced clinical studies to accommodate imposed limitations. In this study, the bioequivalence part could not be conducted as planned. Thus, the aim was to demonstrate bioequivalence, using an adaptive study design, of tadalafil in fixed-dose combination (FDC) tablets of macitentan/tadalafil with single macitentan and tadalafil (Canadian-sourced) tablets and assess the effect of food on FDC tablets in healthy subjects. This Phase 1, single-center, open-label, single-dose, two-part, two-period, randomized, crossover study enrolled 62 subjects. Tadalafil bioequivalence as part of FDC of macitentan/tadalafil (10/40 mg) with single-component tablets of macitentan (10 mg) and tadalafil (40 mg) was determined by pharmacokinetic (PK) assessment under fasted conditions. The effect of food on FDC was evaluated under fed and fasted conditions. Fasted 90% confidence intervals (CIs) for geometric mean ratios (GMRs) were within bioequivalence limits for tadalafil and macitentan. Fed and fasted 90% CIs for area under the curve (AUC) GMR were within bioequivalence limits. However, 90% CIs for maximum plasma concentration (Cmax ) GMR for macitentan and tadalafil were outside bioequivalence limits. One FDC-treated subject experienced a serious adverse event of transient ischemic attack (bioequivalence part). To address pandemic-imposed limitations, an adaptive study design was implemented to demonstrate that the FDC tablet was bioequivalent to the free combination of macitentan and tadalafil (Canadian-sourced). No clinically significant differences in PK were determined between fed and fasted conditions; the FDC formulation could be taken irrespective of meals. The FDC formulation under fasted and fed conditions was well tolerated with no clinically relevant differences in safety profiles between the treatment groups. NCT Number: NCT04235270.

A phase I study of high dose camostat mesylate in healthy adults provides a rationale to repurpose the TMPRSS2 inhibitor for the treatment of COVID-19.

Camostat mesylate, an oral serine protease inhibitor, is used to treat chronic pancreatitis and reflux esophagitis. Recently, camostat mesylate and its active metabolite 4-(4-guanidinobenzoyloxy)phenylacetic acid (GBPA) were reported to inhibit the infection of cells by severe acute respiratory syndrome coronavirus 2 by inhibiting type II transmembrane serine protease. We conducted a phase I study to investigate high-dose camostat mesylate as a treatment for coronavirus disease 2019. Camostat mesylate was orally administered to healthy adults at 600 mg 4 times daily under either of the following conditions: fasted state, after a meal, 30 min before a meal, or 1 h before a meal, and the pharmacokinetics and safety profiles were evaluated. In addition, the time of plasma GBPA concentration exceeding the effective concentration was estimated as the time above half-maximal effective concentration (EC50 ) by using pharmacokinetic/pharmacodynamic modeling and simulation. Camostat mesylate was safe and tolerated at all dosages. Compared with the fasted state, the exposure of GBPA after a meal and 30 min before a meal was significantly lower; however, no significant difference was observed at 1 h before a meal. The time above EC50 was 11.5 h when camostat mesylate 600 mg was administered 4 times daily in the fasted state or 1 h before a meal. Based on the results of this phase I study, we are currently conducting a phase III study.

Emergent Drug and Nutrition Interactions in COVID-19: A Comprehensive Narrative Review.

Coronaviruses are a large family of viruses that are known to cause respiratory tract infections ranging from colds to more severe diseases, such as Middle East Respiratory Syndrome (MERS) and the Severe Acute Respiratory Syndrome (SARS). New Coronavirus Disease 2019 (COVID-19), which led to deaths as well as social and economic disruptions, is an ongoing worldwide pandemic caused by Severe Acute Respiratory Syndrome Coronavirus 2 (SARS-CoV-2). Currently, there is no approved treatment for COVID-19. Hence, only supportive care has been approved by the World Health Organization (WHO) for now. Pharmacological agents used for the adjunctive treatment of COVID-19 following the current literature and clinical experiences include antiviral, anti-inflammatory, and anti-malaria drugs, and other traditional or untraditional treatments. However, it has been reported that the use of these drugs may have some negative effects and comorbidities. Moreover, the current data have indicated that the risk of drug-drug interactions may also be high in polypharmacy cases, especially in elderly people, some comorbidity situations, and intensive care unit (ICU) patients. It is highly possible that these situations can not only increase the risk of drug-drug interactions but also increase the risk of food/nutrition-drug interactions and affect the nutritional status. However, this issue has not yet been entirely discussed in the literature. In this review, current information on the possible mechanisms as well as pharmacokinetic and pharmacodynamic effects of some pharmacological agents used in the treatment of COVID-19 and/or their secondary interactions with nutrition were evaluated and some future directions were given.