Pharmacokinetic Drug-drug Interactions Research Articles

Comprehensive Physiologically Based Pharmacokinetic Model to Assess Drug-Drug Interactions of Phenytoin.

Regulatory agencies worldwide expect that clinical pharmacokinetic drug-drug interactions (DDIs) between an investigational new drug and other drugs should be conducted during drug development as part of an adequate assessment of the drug's safety and efficacy. However, it is neither time nor cost efficient to test all possible DDI scenarios clinically. Phenytoin is classified by the Food and Drug Administration as a strong clinical index inducer of CYP3A4, and a moderate sensitive substrate of CYP2C9. A physiologically based pharmacokinetic (PBPK) platform model was developed using GastroPlus® to assess DDIs with phenytoin acting as the victim (CYP2C9, CYP2C19) or perpetrator (CYP3A4). Pharmacokinetic data were obtained from 15 different studies in healthy subjects. The PBPK model of phenytoin explains the contribution of CYP2C9 and CYP2C19 to the formation of 5-(4'-hydroxyphenyl)-5-phenylhydantoin. Furthermore, it accurately recapitulated phenytoin exposure after single and multiple intravenous and oral doses/formulations ranging from 248 to 900 mg, the dose-dependent nonlinearity and the magnitude of the effect of food on phenytoin pharmacokinetics. Once developed and verified, the model was used to characterize and predict phenytoin DDIs with fluconazole, omeprazole and itraconazole, i.e., simulated/observed DDI AUC ratio ranging from 0.89 to 1.25. This study supports the utility of the PBPK approach in informing drug development.

Optimizing antidepressant and clozapine co-prescription in clinical practice: A systematic review and expert recommendations

ObjectivesTo synthesize the information relevant for clinical practice on clozapine-antidepressant co-prescription concerning pharmacokinetic drug-drug interactions (DDI), adverse drug reactions (ADRs) associated with the co-prescription, antidepressant add-on for clozapine-resistant symptoms and antidepressant add-on for clozapine-induced ADRs. MethodsArticles were identified with MEDLINE, Web of Sciences and PsycINFO search from inception through April 2023. Data were synthesized narratively. ResultsADRs are most often induced by the co-prescription of antidepressants that inhibit CYP enzymes (fluvoxamine, fluoxetine, paroxetine). Fluvoxamine add-on is hazardous because of its potent inhibition of clozapine metabolism and has few indications (lowering daily number of clozapine tablets, reducing norclozapine-induced metabolic disturbances and other dose-dependent clozapine-induced ADRs). ADR frequency may be reduced by therapeutic drug monitoring and knowledge of other factors impacting clozapine metabolism (pneumonia, inflammation, smoking, etc.). Improvement of negative symptoms is the most documented beneficial effect of antidepressant add-on for clozapine-resistant psychotic symptoms. The add-on antidepressant should be chosen according to its safety profile regarding DDI with clozapine: antidepressants inhibiting clozapine metabolism or increasing the anticholinergic load should be avoided. Other indications of antidepressant add-on (affective or obsessive compulsive symptoms, sialorrhea, and enuresis) are poorly documented. ConclusionAntidepressant add-on to clozapine is associated with potential benefits in clozapine users as this strategy may contribute to reduce the burden of clozapine-resistant symptoms or of clozapine-induced ADRs. Further studies are needed to determine whether antidepressant add-on can reduce the risk of clozapine discontinuation.

Revealing the dynamic landscape of drug-drug interactions through network analysis.

Introduction: The landscape of drug-drug interactions (DDIs) has evolved significantly over the past 60years, necessitating a retrospective analysis to identify research trends and under-explored areas. While methodologies like bibliometric analysis provide valuable quantitative perspectives on DDI research, they have not successfully delineated the complex interrelations between drugs. Understanding these intricate relationships is essential for deciphering the evolving architecture and progressive transformation of DDI research structures over time. We utilize network analysis to unearth the multifaceted relationships between drugs, offering a richer, more nuanced comprehension of shifts in research focus within the DDI landscape. Methods: This groundbreaking investigation employs natural language processing, techniques, specifically Named Entity Recognition (NER) via ScispaCy, and the information extraction model, SciFive, to extract pharmacokinetic (PK) and pharmacodynamic (PD) DDI evidence from PubMed articles spanning January 1962 to July 2023. It reveals key trends and patterns through an innovative network analysis approach. Static network analysis is deployed to discern structural patterns in DDI research, while evolving network analysis is employed to monitor changes in the DDI research trend structures over time. Results: Our compelling results shed light on the scale-free characteristics of pharmacokinetic, pharmacodynamic, and their combined networks, exhibiting power law exponent values of 2.5, 2.82, and 2.46, respectively. In these networks, a select few drugs serve as central hubs, engaging in extensive interactions with a multitude of other drugs. Interestingly, the networks conform to a densification power law, illustrating that the number of DDIs grows exponentially as new drugs are added to the DDI network. Notably, we discovered that drugs connected in PK and PD networks predominantly belong to the same categories defined by the Anatomical Therapeutic Chemical (ATC) classification system, with fewer interactions observed between drugs from different categories. Discussion: The finding suggests that PK and PD DDIs between drugs from different ATC categories have not been studied as extensively as those between drugs within the same categories. By unearthing these hidden patterns, our study paves the way for a deeper understanding of the DDI landscape, providing valuable information for future DDI research, clinical practice, and drug development focus areas.

Interactions médicamenteuses de type pharmacocinétique avec les inhibiteurs d’ALK: Pharmacokinetic drug-drug interactions with ALK inhibitors

The ALK inhibitors exhibit an inter-patient variability in clinical response (efficacy, toxicity). The pharmacokinetic variability is one of the factors contributing to this clinical variability. Patients treated with ALK inhibitors are candidates to drug-drug interaction since they are commonly polymedicated for the treatment of their comorbidities, pain and/or adverses events related to the antitumor treatment. Given ALK inhibitors exhibit a narrow therapeutic index, some pharmacokinetic drug-drug interactions can therefore result either in supra-therapeutic plasma concentrations raising the toxic risk or in infra-therapeutic concentrations leading to decreased efficacy. Besides, food or phytotherapy can also significantly altered the pharmacokinetics of some ALK inhibitors. This review focuses on the potential pharmacokinetic drug-drug interactions with ALK inhibitors.1877-1203/© 2023 SPLF. Published by Elsevier Masson SAS. All rights reserved.

Mechanisms and Clinical Significance of Pharmacokinetic Drug Interactions Mediated by FDA and EMA-approved Hepatitis C Direct-Acting Antiviral Agents.

The treatment of patients infected with the hepatitis C virus (HCV) has been revolutionised by the development of direct-acting antiviral agents (DAAs) that target specific HCV proteins involved in viral replication. The first DAAs were associated with clinical problems such as adverse drug reactions and pharmacokinetic drug-drug interactions (DDIs). Current FDA/EMA-approved treatments are combinations of DAAs that simultaneously target the HCV N5A-protein, the HCV N5B-polymerase and the HCV NS3/4A-protease. Adverse events and DDIs are less likely with these DAA combinations but several DDIs of potential clinical significance remain. Much of the available information on the interaction of DAAs with CYP drug-metabolising enzymes and influx and efflux transporters is contained in regulatory summaries and is focused on DDIs of likely clinical importance. Important DDIs perpetrated by current DAAs include increases in the pharmacokinetic exposure to statins and dabigatran. Some mechanistic information can be deduced. Although the free concentrations of DAAs in serum are very low, a number of these DDIs are likely mediated by the inhibition of systemic influx transporters, especially OATP1B1/1B3. Other DDIs may arise by DAA-mediated inhibition of intestinal efflux transporters, which increases the systemic concentrations of some coadministered drugs. Conversely, DAAs are victims of DDIs mediated by cyclosporin, ketoconazole, omeprazole and HIV antiretroviral drug combinations, especially when boosted by ritonavir and, to a lesser extent, cobicistat. In addition, concurrent administration of inducers, such as rifampicin, carbamazepine and efavirenz, decreases exposure to some DAAs. Drug-drug interactions that increase the accumulation of HCV N3/4A-protease inhibitors like grazoprevir may exacerbate hepatic injury in HCV patients.

Hydrocodone, Oxycodone, and Morphine Metabolism and Drug-Drug Interactions.

Awareness of drug interactions involving opioids is critical for patient treatment as they are common therapeutics used in numerous care settings, including both chronic and disease-related pain. Not only do opioids have narrow therapeutic indexes and are extensively used, but they have the potential to cause severe toxicity. Opioids are the classical pain treatment for patients who suffer from moderate to severe pain. More importantly, opioids are often prescribed in combination with multiple other drugs, especially in patient populations who typically are prescribed a large drug regimen. This review focuses on the current knowledge of common opioid drug-drug interactions (DDIs), focusing specifically on hydrocodone, oxycodone, and morphine DDIs. The DDIs covered in this review include pharmacokinetic DDI arising from enzyme inhibition or induction, primarily due to inhibition of cytochrome p450 enzymes (CYPs). However, opioids such as morphine are metabolized by uridine-5'-diphosphoglucuronosyltransferases (UGTs), principally UGT2B7, and glucuronidation is another important pathway for opioid-drug interactions. This review also covers several pharmacodynamic DDI studies as well as the basics of CYP and UGT metabolism, including detailed opioid metabolism and the potential involvement of metabolizing enzyme gene variation in DDI. Based upon the current literature, further studies are needed to fully investigate and describe the DDI potential with opioids in pain and related disease settings to improve clinical outcomes for patients. SIGNIFICANCE STATEMENT: A review of the literature focusing on drug-drug interactions involving opioids is important because they can be toxic and potentially lethal, occurring through pharmacodynamic interactions as well as pharmacokinetic interactions occurring through inhibition or induction of drug metabolism.

Iatrogenic Side Effects of Pain Therapies.

Pain regimens, particularly for chronic cancer and noncancer pain, must balance the important analgesic benefits against potential risks. Many effective and frequently used pain control regimens are associated with iatrogenic adverse events. Interventional procedures can be associated with nerve injuries, vascular injuries, trauma to the spinal cord, and epidural abscesses. Although rare, these adverse events are potentially catastrophic. Pharmacologic remedies for pain must also consider potential side effects that can occur even at therapeutic doses of over-the-counter remedies such as paracetamol (acetaminophen) or nonsteroidal anti-inflammatory drugs. Opioids are effective pain relievers but are associated with many side effects, some of which can be treatment limiting. A prevalent and distressing side effect of opioid therapy is constipation. Opioid-induced constipation is caused by binding to opioid receptors in the gastrointestinal system, making conventional laxatives ineffective. Peripherally acting mu-opioid receptor antagonists are a new drug class that offers the benefits of preserving opioid analgesia without side effects in the gastrointestinal system. An important safety concern, particularly among geriatric patients is the increasingly prevalent condition of polypharmacy. Many senior patients take five or more medications, including some that may be contraindicated in geriatric patients, duplicative of other drugs, have potential pharmacokinetic drug-drug interactions, or may not be the optimal choice for the patient's age and condition. Careful assessment of medications in the elderly, including possibly deprescribing with tapering of certain drugs, may be warranted but should be done systematically and under clinical supervision.

A validated LC-MS/MS bioanalytical method for the pharmacokinetic interaction study of the effect of some co-administered COVID-19 protocol drugs on pholcodine containing antitussive mixture

The symptoms of the viral infection COVID-19, which range from mild to severe, can include fever, coughing, sore throats, malaise, headaches, and a loss of taste or smell. Fever and cough are the most typical symptoms of COVID-19, and in more severe cases, it can make breathing difficult. Hence, in this in-vivo study, we studied the effect of the simultaneous co-administration of COVID-19 treatment drugs (azithromycin, dexamethasone, and hydroxychloroquine) on the pharmacokinetics of the antitussive drugs combination: pholcodine, pseudoephedrine and paracetamol in rats. For the simultaneous determination of pholcodine, pseudoephedrine, and paracetamol in rat plasma, a UPLC-MS/MS technique was developed and approved. a mobile phase made up of 0.15% aqueous formic acid: acetonitrile (20:80, v/v) was used using an Xterra C18 MS column (3.5 m, 4.6 × 50 mm). The detection procedure involved the employment of a multiple reaction monitoring mode utilizing triple-quadrupole tandem mass spectrometer. The concentration range for pholcodine, pseudoephedrine, and paracetamol was linear across 12–1000 ng/ml, 10–550 ng/ml, and 400–30000 ng/ mL, respectively. The results show that the coefficient of variation is satisfactory at quality control samples for all the mentioned drugs, confirming the accuracy and precision of the method. This approach was successfully implemented in a rat drug-drug pharmacokinetic interaction study to determine whether the co-administration of COVID-19 protocol medications would affect the bioavailability of pholcodine, pseudoephedrine and paracetamol. It was found that azithromycin, dexamethasone, and hydroxychloroquine co-administration significantly affect the bioavailability of these drugs, increasing their systemic exposure as a result and this could potentially lead to increasing adverse effects. Therefore, healthcare professionals should consider the potential drug-drug interaction when prescribing these medications to COVID-19 patients.

Tazemetostat synergistically combats multidrug resistance by the unique triple inhibition of ABCB1, ABCC1, and ABCG2 efflux transporters in vitro and ex vivo

ATP-binding cassette (ABC) drug efflux transporters and drug metabolizing enzymes play crucial roles in pharmacokinetic drug-drug interactions and multidrug tumor resistance (MDR). Tazemetostat (EPZ-6438, Tazverik) is a novel epigenetic drug that has been recently approved for the therapy of advanced epithelioid sarcoma and follicular lymphoma. Additionally, this medication is currently being clinically tested to treat several other cancers such as non-small cell lung cancer (NSCLC). This study aimed to investigate the inhibitory effects of tazemetostat on selected ABC transporters/cytochrome P450 3A4 (CYP3A4) enzyme to comprehensively explore its role in MDR. First, our accumulation and molecular docking studies showed that tazemetostat is a unique triple inhibitor of ABCB1, ABCC1, and ABCG2 transporters. In contrast, tazemetostat exhibited only low level of interaction with the CYP3A4 isozyme. Drug combination assays confirmed that tazemetostat is a multipotent MDR modulator able to synergize with various conventional chemotherapeutics in vitro. Subsequent caspase activity assays and microscopic staining of apoptotic nuclei proved that the effective induction of apoptosis is behind the observed synergies. Notably, a potent MDR-modulatory capacity of tazemetostat was recorded in primary ex vivo NSCLC explants generated from patients’ biopsies. On the contrary, its possible position of pharmacokinetic MDR’s victim was excluded in comparative proliferation assays. Finally, tested drug has not been identified as an inducer of resistant phenotype in NSCLC cell lines. In conclusion, we demonstrated that tazemetostat is a unique multispecific chemosensitizer, which has strong potential to overcome limitations seen in the era of traditional MDR modulators.

Pharmacokinetic parameters, safety and drug-drug interactions of mirtazapine and tizanidine, combined in the new original drug Dorsumio®

Objective: to study the pharmacokinetic parameters and safety of Dorsumio® (mirtazapine + tizanidine, extended-release tablets, 15 mg + 6 mg, JSC Valenta Pharm, Russia) taken once by healthy volunteers in comparison with Calixta®, a monocomponent drug (INN: Mirtazapine, filmcoated tablets, 30 mg, Belupo, Drugs and Cosmetics d.d., Republic of Croatia) and Sirdalud® MR (INN: Tizanidine, modified-release capsules, 6 mg, Novartis Pharma AG, Switzerland) with an evaluation of their drug interactions when taken concomitantly or separately.Material and methods. A two-stage, randomized, comparative cross-over study of the pharmacokinetics and safety of the complex drug Dorsumio® was conducted. In the first stage, volunteers alternated between taking one or two tablets of the study drug in two administration periods; in the second stage, subjects alternated between taking the reference monodrugs Calixta® and Sirdalud® MR alone and in a joint combination in three administration periods. A total of 38 volunteers were randomized into the study, of which 14 subjects participated in the first and 24 in the second stage of the study. Quantitative levels of mirtazapine and tizanidine were determined by high-performance liquid chromatography with tandem mass spectrometry. Based on the data obtained, the main pharmacokinetic parameters reflecting the bioavailability of each drug were calculated, and the mutual influence of their combination on pharmacokinetics was also studied. During the study, vital signs and laboratory parameters of the subjects were monitored, and the occurrence of adverse events (AEs) and serious AEs was recorded.Results. A two-fold increase in the dose of the combination drug Dorsumio® resulted in a comparable increase in the pharmacokinetics of the individual drugs. There was no significant reciprocal effect of mirtazapine and tizanidine on their pharmacokinetic parameters. In one of the subjects participating in the second stage of the study, two mild side effects were registered after the joint use of Calixta® and Sirdalud® MR that did not require medical intervention and resolved on their own without health consequences.Conclusion. There were no differences in the safety profile of the combined use of mirtazapine and tizanidine in the form of a free or fixed combination. It was shown that the investigated drug combination had no mutual influence on the pharmacokinetics of the individual components.

In vivo Metabolism of Nifurtimox and the Drug-Drug Interaction Potential Including its Major Metabolites.

Nifurtimox is an effective treatment for patients with Chagas disease, but knowledge of its biotransformation and excretion is limited. This study aimed to better understand the fate of oral nifurtimox in vivo. We investigated the exposure and excretion pathways of [14C]-labeled nifurtimox and its metabolites in rats. We then quantified the prominent metabolites and nifurtimox in the urine and plasma of patients receiving nifurtimox using LC-HRMS with reference standards and quantified these compounds in rat plasma after a single, high dose of nifurtimox. We also investigated potential drug-drug interactions (DDIs) of these compounds in vitro. In rats, orally administered nifurtimox was rapidly absorbed (tmax 0.5 h) and eliminated (t½ 1.4 h). Metabolism of nifurtimox yielded six predominant metabolites (M-1 to M-6) in urine and plasma, and the dose was excreted equally via the renal and fecal routes with only traces of unchanged nifurtimox detectable due to its instability in excreta. In patients with Chagas disease, only M-6 and M-4 achieved relevant exposure levels, and the total amount of excreted metabolites in urine was higher in fed versus fasted patients, consistent with the higher systemic exposure. For nifurtimox, M-6, and M-4, no potential perpetrator pharmacokinetic DDIs with the main cytochrome P- 450 enzymes and drug transporters were identified in vitro. This contemporary analysis of the complex metabolite profile and associated exposures emerging after oral dosing of nifurtimox in rats and humans, together with the expected low risk for clinically relevant DDIs, expands the understanding of this important anti-trypanosomal drug.

Pharmacokinetic and Pharmacodynamic Drug-Drug Interactions: Research Methods and Applications.

Because of the high research and development cost of new drugs, the long development process of new drugs, and the high failure rate at later stages, combining past drugs has gradually become a more economical and attractive alternative. However, the ensuing problem of drug-drug interactions (DDIs) urgently need to be solved, and combination has attracted a lot of attention from pharmaceutical researchers. At present, DDI is often evaluated and investigated from two perspectives: pharmacodynamics and pharmacokinetics. However, in some special cases, DDI cannot be accurately evaluated from a single perspective. Therefore, this review describes and compares the current DDI evaluation methods based on two aspects: pharmacokinetic interaction and pharmacodynamic interaction. The methods summarized in this paper mainly include probe drug cocktail methods, liver microsome and hepatocyte models, static models, physiologically based pharmacokinetic models, machine learning models, in vivo comparative efficacy studies, and in vitro static and dynamic tests. This review aims to serve as a useful guide for interested researchers to promote more scientific accuracy and clinical practical use of DDI studies.

Pharmacokinetic Drug-Drug Interactions Involving Antiretroviral Agents: An Update.

Antiretroviral therapy is the recognized treatment for human immunodeficiency virus (HIV) infection involving several antiviral agents. Even though highly active antiretroviral therapy has been proven to be very effective in suppressing HIV replication, the antiretroviral drugs, belonging to different pharmacological classes, present quite complex pharmacokinetic properties such as extensive drug metabolism and transport by membrane-associated drug carriers. Moreover, due to uncomplications or complications in HIV-infected populations, an antiretroviralbased multiple-drug coadministration therapy strategy is usually applied for treatment effect, thus raising the possibility of drug-drug interactions between antiretroviral drugs and common drugs such as opioids, stains, and hormonal contraceptives. Herein, thirteen classical antiretroviral drugs approved by US Food and Drug Administration were summarized. Besides, relative drug metabolism enzymes and transporters known to interact with those antiretroviral drugs were detailed and described. Furthermore, one after the summarized antiretroviral drugs, the drug-drug interactions between two antiretroviral drugs or antiretroviral drug - conventional medical drugs of the past decade were discussed and summarized. This review is intended to deepen the pharmacological understanding of antiretroviral drugs and promote more secure clinical applications for antiretroviral drugs to treat HIV.

Pharmacokinetic Drug-Drug Interactions: A Systematic Review of the Cytochrome P450 (CYP) Isoenzyme 3A4

The cytochrome P450 (CYP) isoenzyme 3A4 or CYP3A4 is a major drug-metabolizing enzyme that has the potential to cause pharmacokinetic drug-drug interactions. Primary research studies have demonstrated CYP3A4-mediated drug-drug interactions through a variety of mechanisms. However, there has been no review during the last 10 years of pharmacokinetic drug-drug interactions mediated by CYP3A4 isoenzymes. It is necessary to systematically review the pharmacokinetic drug-drug interactions mediated by CYP3A4. Source review of articles were retrieved from the PubMed and Scopus databases. The preparation of keywords through the population, intervention, comparison, and outcomes (PICO) method written based on the Boolean operator. Reporting the results of the paper search is presented in the Prisma version 1 2020 flowchart. The risk of bias assessment used COHORT tools and Systematic Review Center for Laboratory Animal Experimentation (SYRCLE) tools. Data was analyzed narratively. Pharmacokinetic drug interactions are mediated by CYP3A4 through the mechanism of induction, activation, inhibition, and inactivation. Induction or activation of CYP3A4 can cause an increase in CYP3A4 expression, so that the drug is metabolized more quickly and has the potential to lose drug efficacy. Inhibition and inactivation of CYP3A4 causes plasma drug levels to increase and drug elimination time to last longer. CYP3A4 plays a major role in the bioactivation of drugs that cause hepatotoxicity through the formation of reactive metabolites. The use of drugs needs to be monitored to avoid pharmacokinetic drug interactions.

Pharmacokinetics and Drug-Drug Interaction of Ocedurenone (KBP-5074) in vitro and in vivo.

Ocedurenone (KBP-5074) is a novel nonsteroidal mineralocorticoid receptor antagonist that has demonstrated safety and efficacy in clinical trials in patients with uncontrolled hypertension and stage 3b/4 chronic kidney disease. This study evaluated the involvement of cytochrome P450 (CYP) isozymes and drug transporters in the biotransformation of ocedurenone, and whether ocedurenone inhibited or induced CYP enzymes and transporters. Clinical pharmacokinetic drug-drug interaction (DDI) of ocedurenone with CYP3A inhibitor and inducer were investigated in healthy volunteers. In vitro tests were conducted to determine which CYP enzymes were involved in ocedurenone's metabolism and whether ocedurenone inhibited or induced these CYP enzymes; ocedurenone substrate characteristics for efflux and uptake transporters and its inhibitory potential on major drug transporters were also assessed. A clinical DDI study was conducted in healthy volunteers to evaluate the effects of a strong CYP3A inhibitor (itraconazole) and inducer (rifampin) on ocedurenone's pharmacokinetics. The in vitro study showed that ocedurenone was primarily metabolized by CYP3A4 and that it did not inhibit CYP enzymes. Ocedurenone appeared to be a substrate of BCRP and P-gp efflux transporters and inhibited BCRP, BSEP, MDR1, MATE1 and 2-K, OATP1B1/3, and OCT1. The clinical DDI study showed that itraconazole reduced ocedurenone's oral clearance by 51% and increased area under the plasma concentration-time curve extrapolated to infinity(AUC0-inf) by104%, while rifampin increased its oral clearance by 6.4-fold and decreased plasma AUC0-inf by 84%. Ocedurenone was shown to be a CYP3A substrate, with no inhibition potential on major drug metabolizing CYP enzymes and transporters at clinical efficacious doses. Ocedurenone did not induce CYP1A2 and 3A4 activity in cultured human primary hepatocytes. Clinical DDI study indicated ocedurenone was well tolerated when administered as a single 0.5-mg dose both alone and with itraconazole or rifampin, and while itraconazole had a weak effect on ocedurenone's pharmacokinetics, rifampin had a significant effect reducing systemic exposures.

Pharmacokinetic and Pharmacodynamic Drug-Drug Interactions between Evogliptin and Empagliflozin or Dapagliflozin in Healthy Male Volunteers.

Evogliptin is a novel dipeptidyl peptidase-4 inhibitor (DPP4i) for glycemic control in patients with type 2 diabetes mellitus(T2DM). This study evaluated the pharmacokinetic (PK) and pharmacodynamic (PD) interactions between evogliptin and sodium glucose cotransporter-2 inhibitors (SGLT2i) in healthy volunteers since combination therapy of DPP4i and SGLT2i has been considered as effective option for T2DM treatment. A randomized, open-label, multiple-dose, two-arm, three-period, three treatments, two-sequence crossover study was conducted in healthy Korean volunteers. In arm 1, subjects were administered 5 mg of evogliptin once daily for 7 days (EV), 25 mg of empagliflozin once daily for 5 days (EP), and the combination once daily for 5 days (EV+EP). In arm 2, subjects were administered 5 mg of evogliptin once daily for 7 days (EV), 10 mg of dapagliflozin once daily for 5 days (DP), and the combination once daily for 5 days (EV+DP). Serial blood samples were collected for PK analysis, and oral glucose tolerance tests were conducted for PD analysis. In each arm, a total of 18 subjects completed the study. All adverse events were mild with no serious adverse events. The geometric mean ratio and confidence interval of the main PK parameters (Cmax,ss and AUCτ,ss ) between EV and either EP or DP alone were not significantly altered by co-administration. Administration of EV+EP or EV+DP did not result in significant PD changes, as determined by the glucose-lowering effect. Administration of EV+EP or EV+DP had no significant effects on the PK profiles of each drug. All treatments were well-tolerated.

Gut Microbiota-Mediated Pharmacokinetic Drug-Drug Interactions between Mycophenolic Acid and Trimethoprim-Sulfamethoxazole in Humans.

Mycophenolic acid (MPA) and trimethoprim-sulfamethoxazole (TMP-SMX) are commonly prescribed together in certain groups of patients, including solid organ transplant recipients. However, little is known about the pharmacokinetic drug-drug interactions (DDIs) between these two medications. Therefore, the present study aimed to determine the effects of TMP-SMX on MPA pharmacokinetics in humans and to find out the relationship between MPA pharmacokinetics and gut microbiota alteration. This study enrolled 16 healthy volunteers to take a single oral dose of 1000 mg mycophenolate mofetil (MMF), a prodrug of MPA, administered without and with concurrent use of TMP-SMX (320/1600 mg/day) for five days. The pharmacokinetic parameters of MPA and its glucuronide (MPAG) were measured using high-performance liquid chromatography. The composition of gut microbiota in stool samples was profiled using a 16S rRNA metagenomic sequencing technique during pre- and post-TMP-SMX treatment. Relative abundance, bacterial co-occurrence networks, and correlations between bacterial abundance and pharmacokinetic parameters were investigated. The results showed a significant decrease in systemic MPA exposure when TMP-SMX was coadministered with MMF. Analysis of the gut microbiome revealed altered relative abundance of two enriched genera, namely the genus Bacteroides and Faecalibacterium, following TMP-SMX treatment. The relative abundance of the genera Bacteroides, [Eubacterium] coprostanoligenes group, [Eubacterium] eligens group, and Ruminococcus appeared to be significantly correlated with systemic MPA exposure. Coadministration of TMP-SMX with MMF resulted in a reduction in systemic MPA exposure. The pharmacokinetic DDIs between these two drugs were attributed to the effect of TMP-SMX, a broad-spectrum antibiotic, on gut microbiota-mediated MPA metabolism.

Pharmacokinetic interaction of voriconazole and clarithromycin in Pakistani healthy male volunteers: a single dose, randomized, crossover, open-label study.

Background: Voriconazole an antifungal drug, has a potential for drug-drug interactions (DDIs) with administered drugs. Clarithromycin is a Cytochromes P450 CYP (3A4 and 2C19) enzyme inhibitor, and voriconazole is a substrate and inhibitor of these two enzymes. Being a substrate of the same enzyme for metabolism and transport, the chemical nature and pKa of both interacting drugs make these drugs better candidates for potential pharmacokinetic drug-drug interactions (PK-DDIs). This study aimed to evaluate the effect of clarithromycin on the pharmacokinetic profile of voriconazole in healthy volunteers. Methods: A single oral dose, open-label, randomized, crossover study was designed for assessing PK-DDI in healthy volunteers, consisting of 2weeks washout period. Voriconazole, either alone (2mg × 200mg, tablet, P/O) or along with clarithromycin (voriconazole 2mg × 200mg, tablet + clarithromycin 500mg, tablet, P/O), was administered to enrolled volunteers in two sequences. The blood samples (approximately 3 cc) were collected from volunteers for up to 24h. Plasma concentrations of voriconazole were analyzed by an isocratic, reversed-phase high-performance-liquid chromatography ultraviolet-visible detector (RP HPLC UV-Vis) and a non-compartmental method. Results: In the present study, when voriconazole was administered with clarithromycin versus administered alone, a significant increase in peak plasma concentration (Cmax) of voriconazole by 52% (geometric mean ratio GMR: 1.52; 90% CI 1.04, 1.55; p = 0.000) was observed. Similarly, the area under the curve from time zero to infinity (AUC0-∞) and the area under the concentration-time curve from time zero to time-t (AUC0-t) of voriconazole also significantly increased by 21% (GMR: 1.14; 90% CI 9.09, 10.02; p = 0.013), and 16% (GMR: 1.15; 90% CI 8.08, 10.02; p = 0.007), respectively. In addition, the results also showed a reduction in the apparent volume of distribution (Vd) by 23% (GMR: 0.76; 90% CI 5.00, 6.20; p = 0.051), and apparent clearance (CL) by 13% (GMR: 0.87; 90% CI 41.95, 45.73; p = 0.019) of voriconazole. Conclusion: The alterations in PK parameters of voriconazole after concomitant administration of clarithromycin are of clinical significance. Therefore, adjustments in dosage regimens are warranted. In addition, extreme caution and therapeutic drug monitoring are necessary while co-prescribing both drugs. Clinical Trial Registration: clinicalTrials.gov, Identifier NCT05380245.

A clinical pharmacokinetic drug-drug interaction study between dextromethorphan and emvododstat, a potent anti-SARS-CoV-2 dihydroorotate dehydrogenase inhibitor

PurposeA therapeutic agent that targets both viral replication and the hyper-reactive immune response would offer a highly desirable treatment for severe acute respiratory syndrome corona virus 2 (SARS-CoV-2, coronavirus disease 2019, COVID-19) management. Emvododstat (PTC299; 4-chlorophenyl 6-chloro-1-[4-methoxyphenyl]-1,3, 4,9-tetrahydro-2H-pyrido[3,4-b]indole-2-carboxylate) was found to be a potent inhibitor of immunomodulatory and inflammation-related processes by inhibition of dihydroorotate dehydrogenase to reduce the severity of SARS-CoV-2 infections This drug interaction study was performed to determine if emvododstat was an inhibitor of CYP2D6.MethodsPotential drug-drug interactions between emvododstat and a CYP2D6 probe substrate (dextromethorphan) were investigated by measuring plasma dextromethorphan and metabolite (dextrorphan) concentrations before and after emvododstat administration. On day 1, 18 healthy subjects received an oral dose of 30 mg dextromethorphan followed by a 4-day washout period. On day 5, subjects received an oral dose of 250 mg emvododstat with food. Two hours later, 30 mg dextromethorphan was administered.ResultsWhen given with emvododstat, plasma dextromethorphan concentrations increased substantially, while metabolite levels (dextrorphan) remained essentially the same. Maximum plasma dextromethorphan concentration (Cmax) increased from 2006 to 5847 pg/mL. Dextromethorphan exposure (AUC) increased from 18,829 to 157,400 h·pg/mL for AUC0-last and from 21,585 to 362,107 h·pg/mL for AUC0-inf following administration of emvododstat. When dextromethorphan parameters were compared before and after emvododstat, least squares mean ratios (90% confidence interval) were found to be 2.9 (2.2, 3.8), 8.4 (6.1, 11.5), and 14.9 (10.0, 22.1) for Cmax, AUC0-last, and AUC0-inf, respectively.ConclusionEmvododstat appears to be a strong CYP2D6 inhibitor. No drug-related treatment emergent adverse effects (TEAEs) were considered to be severe or serious.Trial registrationEudraCT 2021-004626-29, 11 May 2021.

Knowledge gaps and educational needs for common cancer therapy-related cardiovascular toxicities and related drug interactions.

e13672 Background: Unprecedented growth in novel oncolytic agents has led to an increase in the complexity of cancer management, including cancer therapy-related cardiovascular toxicities (CTR-CVTs) and related pharmacodynamic (PD) and pharmacokinetic (PK) drug-drug interactions (DDIs). The intent of this survey is to assess the landscape of CTR-CVTs including health care provider (HCP) educational needs. Methods: A 20-question survey was distributed to HCPs primarily specializing in cardiology, oncology, hematology and cardio-oncology. The survey was distributed on email listservs of targeted organizations, including the International Cardio-Oncology Society. In addition to demographics, the survey assessed CTR-CVTs and related DDIs encountered. Perceived knowledge gaps were also assessed. Data was analyzed and summarized utilizing descriptive statistics. Results: Of 220 survey respondents, 46% were pharmacists and 54% were other HCPs ( > 80% physicians). Respondents predominately practiced in North America (59%) or Europe (20%), with the majority at academic medical centers (65% academic, 35% community) and primarily specializing in cardiology (71%, cardiology, 26% oncology, 14% hematology). Types of malignancies managed were primarily solid tumors (74%), however hematological malignancy management was also common ( > 60%). All HCPs reported encountering the following CTR-CVTs most commonly: cancer therapy-related cardiac dysfunction (CTRCD) (88%), hypertension (HTN) (79%) and thromboembolic disease (71%). Overall, pharmacists reported managing CTR-CVTs less frequently than other HCPs, especially regarding atrial fibrillation/flutter, coronary artery disease/vasospasm and bradycardia/AV block. The most common cardio-oncology-related PD DDIs encountered were CTRCD and QT prolongation/Torsades de Pointes (QTP/TdP). The most frequently managed cardio-oncology-related PK DDIs included antiarrhythmic agents, direct-acting oral anticoagulants and antiplatelet agents. All HCPs reported greatest comfort managing anthracycline/HER2 targeted therapy-associated CTRCD and least comfort managing arsenic-associated QTP. Immune checkpoint inhibitor-associated myocarditis (74%), immune modulator-associated thrombosis/thrombotic events (64%), Bruton tyrosine kinase inhibitor associated bleeding (58%) and atrial fibrillation (55%) were ranked of highest educational need. Overall, responses for PD/PK DDIs and educational recommendations were similar between pharmacists and other HCPs. Conclusions: This survey provides insight on the most commonly encountered CTR-CVTs and related DDIs as well as knowledge gaps of HCPs managing CTR-CVTs. These specific areas should be targeted for future educational initiatives to optimize the cardiovascular care of patients with cancer.