Increased warfarin requirements in a patient with chronic hepatitis C infection receiving sofosbuvir and ribavirin

Drug-drug interactions with candidate medications used for COVID-19 treatment: An overview

Drug-drug interaction (DDI) is a common clinical problem that has occurred as a result of the concomitant use of multiple drugs. DDI may occur in patients under treatment with medications used for coronavirus disease 2019 (COVID-19; i.e., chloroquine, lopinavir/ritonavir, ribavirin, tocilizumab, and remdesivir) and increase the risk of serious adverse reactions such as QT-prolongation, retinopathy, increased risk of infection, and hepatotoxicity. This review focuses on summarizing DDIs for candidate medications used for COVID-19 in order to minimize the adverse reactions.

Drug interactions: a review of the unseen danger of experimental COVID-19 therapies

As global health services respond to the coronavirus pandemic, many prescribers are turning to experimental drugs. This review aims to assess the risk of drug-drug interactions in the severely ill COVID-19 patient. Experimental therapies were identified by searching ClinicalTrials.gov for 'COVID-19', '2019-nCoV', '2019 novel coronavirus' and 'SARS-CoV-2'. The last search was performed on 30 June 2020. Herbal medicines, blood-derived products and in vitro studies were excluded. We identified comorbidities by searching PubMed for the MeSH terms 'COVID-19', 'Comorbidity' and 'Epidemiological Factors'. Potential drug-drug interactions were evaluated according to known pharmacokinetics, overlapping toxicities and QT risk. Drug-drug interactions were graded GREEN and YELLOW: no clinically significant interaction; AMBER: caution; RED: serious risk. A total of 2378 records were retrieved from ClinicalTrials.gov, which yielded 249 drugs that met inclusion criteria. Thirteen primary compounds were screened against 512 comedications. A full database of these interactions is available at www.covid19-druginteractions.org. Experimental therapies for COVID-19 present a risk of drug-drug interactions, with lopinavir/ritonavir (10% RED, 41% AMBER; mainly a perpetrator of pharmacokinetic interactions but also risk of QT prolongation particularly when given with concomitant drugs that can prolong QT), chloroquine and hydroxychloroquine (both 7% RED and 27% AMBER, victims of some interactions due to metabolic profile but also perpetrators of QT prolongation) posing the greatest risk. With management, these risks can be mitigated. We have published a drug-drug interaction resource to facilitate medication review for the critically ill patient.

How to overcome cardiovascular challenges in COVID-19 patients: a guide for common practice

The COVID-19 epidemic initially started in Wuhan, China in December 2019 due to SARS-CoV-2. SARS-CoV-2 is genetically similar to the bat beta-coronavirus genus, but the novel specie of this genus can infect humans. The most common clinical features of COVID-19 are fever, cough, myalgia, fatigue, expectoration, and dyspnea. The primary reported mortality rate was about 2-3% in China; however, it reached up to 10% among patients with underlying cardiovascular diseases. The primary epidemiological investigations showed a high prevalence of underlying cardiovascular diseases in more than 40% of infected patients. A high prevalence of hypertension, ischemic heart disease, and diabetes were reported among deceased patients in Italy. Previous experiments in different pandemic situations showed that the cardiovascular system has been affected in many ways. Previous studies on SARS-CoV and MERS-CoV reported that cardiovascular co-morbidities had a direct correlation with the risk of infection, the severity of disease, and the mortality rate. Therefore, brief and available protocols for controlling the negative effects of this novel respiratory infection on the cardiovascular system, especially in a high-risk populations with underlying cardiovascular conditions, is one of the most serious concerns among healthcare providers. Herein, we aimed to review the available data on the cardiac manifestation of COVID-19. Besides, we described useful maps for the better treatment of COVID-19 infection in patients with underlying cardiovascular conditions, as a high-risk group of patients.

Acute Coronary Syndromes and Covid-19: Exploring the Uncertainties

Since an association between myocardial infarction (MI) and respiratory infections has been described for influenza viruses and other respiratory viral agents, understanding possible physiopathological links between severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) and acute coronary syndromes (ACS) is of the greatest importance. The initial data suggest an underestimation of ACS cases all over the world, but acute MI still represents a major cause of morbidity and mortality worldwide and should not be overshadowed during the coronavirus disease (Covid-19) pandemic. No common consensus regarding the most adequate healthcare management policy for ACS is currently available. Indeed, important differences have been reported between the measures employed to treat ACS in China during the first disease outbreak and what currently represents clinical practice across Europe and the USA. This review aims to discuss the pathophysiological links between MI, respiratory infections, and Covid-19; epidemiological data related to ACS at the time of the Covid-19 pandemic; and learnings that have emerged so far from several catheterization labs and coronary care units all over the world, in order to shed some light on the current strategies for optimal management of ACS patients with confirmed or suspected SARS-CoV-2 infection.

Decreased warfarin sensitivity among patients treated with elbasvir and grazoprevir for hepatitis C infection

PURPOSE

We previously reported an interaction with warfarin anticoagulation when initiating treatment with direct-acting antiviral agents for hepatitis C infection. A decreased warfarin sensitivity led to subtherapeutic anticoagulation. To study this interaction further, we expanded our research to include patients treated with the combination of elbasvir and grazoprevir concurrent with warfarin anticoagulation and investigated changes in warfarin sensitivity during and after treatment.

METHODS

Using electronic health records of the Veterans Health Administration, patients starting treatment with elbasvir-grazoprevir for hepatitis C infection concurrent with warfarin anticoagulation were identified. Inclusion required stable warfarin anticoagulation prior to 12 weeks of treatment with elbasvir-grazoprevir. A warfarin sensitivity index (WSI) was calculated at the start of treatment, after 12 weeks after treatment, and at the end of treatment. The primary endpoint was the difference in WSI from pre- to end-treatment. The secondary endpoint was the WSI difference from before treatment to Changes in International Normalized Ratio, warfarin doses, and time in therapeutic range were measured.

RESULTS

In the final sample of 43 patients, the mean WSI decreased during treatment from 0.53 to 0.40, or 25.2%. After treatment, the mean WSI rose to 0.51. Although the mean weekly warfarin dose increased from 40.3 to 44.6 mg during treatment, the mean International Normalized Ratio decreased from 2.40 to 1.96, recovering to 2.59 after treatment. The time spent in therapeutic range decreased from 74.1% before treatment to 39.8% during treatment and back to 64.9% 12 weeks posttreatment.

CONCLUSION

When elbasvir-grazoprevir was added to stable warfarin anticoagulation, warfarin sensitivity decreased significantly during treatment and returned to baseline after treatment.