Nicolas Venisse1,2. 1. INSERM CIC1402, University Hospital of Poitiers, University of Poitiers, Poitiers Cedex, 86021, France. 2. Biology-Pharmacy-Public Health Department, University Hospital of Poitiers, 2 Rue de la Milétrie, Poitiers Cedex, 86021, France.
Pharmacologists, pharmacists, and other drug experts have been at the forefront during the COVID‐19 outbreak. Pharmacological expertise was required in various areas such as the daily health care of patients admitted to our hospitals [1], the implementation of pharmacokinetic and pharmacokinetic‐pharmacodynamic studies in clinical trials of repurposed drugs [2], and even in providing up‐to‐date information to the general population [3].Assessment of drug–drug interactions is one of the areas of pharmacological expertise that directly contributes to patient health care through the effective and safe management of pharmacotherapy. Indeed, drug–drug interactions are an underrecognized source of medical errors, which have major health consequences and significantly increase health costs. This has been thoroughly demonstrated in the aging population presenting with increasing multimorbidity and polypharmacy. Thereby, assessing drug–drug interactions is of primary importance in the context of COVID‐19 therapy where older patients and those presenting with co‐morbidities (hypertension, diabetes, chronic kidney disease, etc.) are those particularly at risk for severe illness. It is also of primary importance for the COVID‐19 patients admitted in intensive care units and receiving treatments for critical care and complications.In their review published in this new issue of Fundamental and Clinical Pharmacology, Lemaitre et al. [4] propose to extensively analyze the potential for drug–drug interactions of drugs being tested to treat COVID‐19. They considered drug–drug interactions from a pharmacokinetic point of view at each step of the ADME process and also from a pharmacodynamic point of view. For that purpose, they used data from various sources: (i) dedicated interaction studies using a cross‐over design, (ii) data from retrospective studies and case reports, and (iii) quantitative prediction using in vivo data. Drugs of interest were those currently being tested to treat COVID‐19: hydroxychloroquine, favipiravir, remdesivir, lopinavir, interferon, tocilizumab, sarilumab, anakinra, and azithromycin. One should acknowledge that COVID‐19 treatment is a fast‐moving area and that, at this time, there is still no high‐quality evidence to support the efficacy of these drugs in COVID‐19. In their review, Lemaitre et al. [4] not only propose a quantitative assessment of drug–drug interaction but also make some suggestions for alternatives and for dosing adjustment. In some cases, therapeutic drug monitoring is proposed to guide dosing adjustment. Of note, the French agency for AIDS and viral hepatitis research (ANRS) and the French Society of Pharmacology and Therapeutics recently issued a document providing recommendations for therapeutic monitoring of drugs used for COVID‐19 treatment (https://sfpt‐fr.org/recommandations‐et‐publications/1162‐recommandations‐anrs‐sfpt‐pour‐le‐stp‐du‐lopinavir‐ritonavir‐et‐de‐l‐hydroxychloroquine‐chez‐les‐patients‐trait%C3%A9s‐pour‐une‐infection‐%C3%A0‐sars‐cov‐2).This review was endorsed by two representative societies in clinical pharmacology: the French Society of Pharmacology and Therapeutics (SFPT) and the International Association of Therapeutic Drug Monitoring and Clinical Toxicology (IATDMCT). Members of both societies are actively involved in the fight against COVID. The SFPT has developed a ‘Question and Answer’ website on the proper use of drugs during the COVID‐19 pandemic dedicated to the general population (https://sfpt‐fr.org/covid19), and the IATDMCT has proposed a list of resources for information on COVID‐19 (https://www.iatdmct.org/rss/7‐news/556‐covid‐19‐resources.html). Both societies have proposed position papers [5] and review articles on the pharmacotherapy of COVID‐19 [6].This review by Lemaitre et al. [4] offers healthcare providers and researchers involved in the fight against the pandemic a resource for understanding the core principles of drug–drug interactions in this era of COVID‐19 and for finding useful information for effective and safe pharmacotherapy.