Safety of Pharmacotherapy in COVID-19 Patients: A Literature Review.

The safety of COVID-19 pharmacotherapy is a relevant issue, first of all, because of the current lack of experience with using particular medicinal products and with off-label prescribing. The aim of the study was to analyse information on potential adverse drug reactions (ADRs) and their predictors in etiology- and pathogenesis-oriented COVID-19 therapy. According to literature data, the main clinically significant risk factors for COVID-19 patients to develop an ADR are the duration of their hospital stay, combined use of antivirals, polypharmacy, and their history of drug allergies. The most common adverse reactions to antivirals, to virus-neutralising antibodies, and to human anti-COVID-19 immunoglobulin and convalescent plasma are, respectively, gastrointestinal and hepatobiliary disorders;gastrointestinal disorders, neurological disorders, and allergic reactions;and transfusion reactions (fever, chills, etc.). For pathogenesis-oriented therapy with systemic glucocorticosteroids, the most characteristic ADR is hyperglycaemia. Janus kinase inhibitors and interleukin inhibitors are most often associated with gastrointestinal disorders and hypertransaminasemia;neutropenia is also characteristic of a number of interleukin inhibitors. Haemostatic adverse reactions to anticoagulants depend on the patient's dosing regimen and condition. Drug-drug interactions are a common problem in COVID-19 treatment, with the combination of nirmatrelvir and ritonavir showing the largest number of significant interactions attributed to their pharmacokinetics. Currently, there is data on the role of pharmacogenetic biomarkers in the safety and clinical outcomes of COVID-19 therapy. Thus, to improve the safety of COVID-19 therapy, an integrated approach is needed that will take into account both the clinical, demographic, and pharmacogenetic predictors of ADRs and the risk of drug-drug interactions.Copyright © 2023 Safety and Risk of Pharmacotherapy. All rights reserved.

Oral anti-viral therapy for early COVID-19 infection in patients with haematological malignancies: A multicentre prospective cohort.

High rates of lung failure have been reported in haematological patients after SARS-CoV2 infection. An early administration of monoclonal antibodies or anti-virals may improve the prognosis. Oral anti-virals may have a wider use independently of the genetic variations of the virus. Prospective data on anti-virals in haematological malignancies (HMs) are still lacking. Outpatients diagnosed with HM and early COVID-19 infection were prospectively treated with the oral anti-virals nirmatrelvir/ritonavir and molnupiravir. Incidence of lung failure, deaths and adverse events was analysed. Long-term outcome at third month was evaluated. Eighty-two outpatients were evaluable for the study objectives. All patients had been treated for their HM within 12 months. COVID-19-related lung failure was 23.1%. Active HM (aOR = 4.42; p = 0.038) and prolonged viral shedding (aOR = 1.04; p = 0.022) resulted independent predictors of severe infection. The vaccination with three to four doses (aOR = 0.02; p = 0.001) and with two doses (aOR = 0.06; p = 0.006) resulted protective. COVID-19-related deaths at 28 days were 6.1%. All-cause mortality at 90-day follow-up was 13.4% (n. 11) and included opportunistic infections and cardiovascular events. In conclusion, this approach reduced the incidence of lung failure and specific mortality compared to previous cohorts, but patients remain at high risk of further complications.

Efficacy of Sotrovimab (SOT), Molnupiravir (MOL), and Nirmatrelvir/Ritponavir (N/R) and Tolerability of Molnupiravir in Outpatients at High Risk for Severe COVID-19.

OBJECTIVE: The main goal of this study was to assess the potential clinical impact of an outpatient administration of available antivirals including SOT, N/R, and MOL to COVID-19 patients at high risk for disease progression. METHODS: We conducted a retrospective analysis on 2606 outpatient individuals with mild to moderate COVID-19 at risk for disease progression, hospitalization, or death. After receiving either SOT (420/2606), MOL (1788/2606), or N/R (398/2606), patients were followed-up with regarding primary (hospitalization rate) and secondary (treatment and side effects) outcomes by phone. RESULT: A total of 2606 patients were treated at the outpatient clinic (SOT: 420; N/R: 398; MOL: 1788). 3.2% of the SOT patients (1 ICU admission), 0.8% of the MOL patients (2 ICU admissions), and none of the N/R patients were hospitalized. 14.3% of the N/R patients reported strong to severe side effects, exceeding SOT (2.6%) and MOL (5%) patients. A reduction in COVID symptoms after the treatment was experienced by 43% of patients in both the SOT and MOL groups and by 67% of patients in the N/R group, respectively. Women had a higher chance of symptom improvement with MOL (OR 1.2, 95%CI 1.0-1.5). CONCLUSION: All antiviral treatment options effectively prevented hospitalization in high-risk COVID-19 patients and were well tolerated. Side effects were pronounced in patients with N/R.

Estimation of Intangible Costs for Factors Associated with Oral Antiviral Drugs for COVID-19 Treatment: A Conjoint Analysis in Japan.

INTRODUCTION: During the recent coronavirus disease 2019 (COVID-19) pandemic, preferences for factors associated with vaccines have been evaluated. Three oral antiviral drugs have been approved in Japan for patients with mild-to-moderate I COVID-19 symptoms. Although preferences for the drugs may also depend on various factors, these have not been fully evaluated. METHODS: A conjoint analysis was performed based on an online survey in August 2022 to estimate the intangible costs of factors associated with oral antiviral drugs for COVID-19. Respondents were individuals aged 20-69 across Japan. The attributes included the company (Japanese/foreign) that developed the drug, formulation and size of the drug, frequency of administration per day, number of tablets/capsules per dose, number of days until no longer infectious to others, and out-of-pocket expenses. A logistic regression model was applied to estimate the utility of each level for each attribute. The intangible costs were calculated by comparing the utility to the out-of-pocket attribute. RESULTS: Responses were collected from 11,303 participants. The difference between levels was the largest for companies that developed a drug; the intangible costs were JPY 5390 higher for the foreign company than for the Japanese company. The next largest difference was in the number of days until one is no longer infectious. For the same formulation, the intangible cost was lower for small sizes than large sizes. For similar-sized tablets and capsules, the intangible cost was lower for tablets than capsules. These tendencies were similar regardless of COVID-19 infection history and the presence of risk factors for severe COVID-19 in the respondents. CONCLUSION: Intangible costs for factors associated with oral antiviral drugs among the Japanese population were estimated. The results may change as the number of people with a history of COVID-19 infection increases and significant progress is made regarding treatments.

Molnupiravir, Nirmatrelvir/Ritonavir, or Sotrovimab for High-Risk COVID-19 Patients Infected by the Omicron Variant: Hospitalization, Mortality, and Time until Negative Swab Test in Real Life.

Background. Several drugs which are easy to administer in outpatient settings have been authorized and endorsed for high-risk COVID-19 patients with mild-moderate disease to prevent hospital admission and death, complementing COVID-19 vaccines. However, the evidence on the efficacy of COVID-19 antivirals during the Omicron wave is scanty or conflicting. Methods. This retrospective controlled study investigated the efficacy of Molnupiravir or Nirmatrelvir/Ritonavir (Paxlovid®) or Sotrovimab against standard of care (controls) on three different endpoints among 386 high-risk COVID-19 outpatients: hospital admission at 30 days; death at 30 days; and time between COVID-19 diagnosis and first negative swab test result. Multivariable logistic regression was employed to investigate the determinants of hospitalization due to COVID-19-associated pneumonia, whereas time to first negative swab test result was investigated by means of multinomial logistic analysis as well as Cox regression analysis. Results. Only 11 patients (overall rate of 2.8%) developed severe COVID-19-associated pneumonia requiring admission to hospital: 8 controls (7.2%); 2 patients on Nirmatrelvir/Ritonavir (2.0%); and 1 on Sotrovimab (1.8%). No patient on Molnupiravir was institutionalized. Compared to controls, hospitalization was less likely for patients on Nirmatrelvir/Ritonavir (aOR = 0.16; 95% CI: 0.03; 0.89) or Molnupiravir (omitted estimate); drug efficacy was 84% for Nirmatrelvir/Ritonavir against 100% for Molnupiravir. Only two patients died of COVID-19 (rate of 0.5%), both were controls, one (a woman aged 96 years) was unvaccinated and the other (a woman aged 72 years) had adequate vaccination status. At Cox regression analysis, the negativization rate was significantly higher in patients treated with both antivirals-Nirmatrelvir/Ritonavir (aHR = 1.68; 95% CI: 1.25; 2.26) or Molnupiravir (aHR = 1.45; 95% CI: 1.08; 1.94). However, COVID-19 vaccination with three (aHR = 2.03; 95% CI: 1.51; 2.73) or four (aHR = 2.48; 95% CI: 1.32; 4.68) doses had a slightly stronger effect size on viral clearance. In contrast, the negativization rate reduced significantly in patients who were immune-depressed (aHR = 0.70; 95% CI: 0.52; 0.93) or those with a Charlson index ≥5 (aHR = 0.63; 0.41; 0.95) or those who had started the respective treatment course 3+ days after COVID-19 diagnosis (aOR = 0.56; 95% CI: 0.38; 0.82). Likewise, at internal analysis (excluding patients on standard of care), patients on Molnupiravir (aHR = 1.74; 95% CI: 1.21; 2.50) or Nirmatrelvir/Ritonavir (aHR = 1.96; 95% CI: 1.32; 2.93) were more likely to turn negative earlier than those on Sotrovimab (reference category). Nonetheless, three (aHR = 1.91; 95% CI: 1.33; 2.74) or four (aHR = 2.20; 95% CI: 1.06; 4.59) doses of COVID-19 vaccine were again associated with a faster negativization rate. Again, the negativization rate was significantly lower if treatment started 3+ days after COVID-19 diagnosis (aHR = 0.54; 95% CI: 0.32; 0.92). Conclusions. Molnupiravir, Nirmatrelvir/Ritonavir, and Sotrovimab were all effective in preventing hospital admission and/or mortality attributable to COVID-19. However, hospitalizations also decreased with higher number of doses of COVID-19 vaccines. Although they are effective against severe disease and mortality, the prescription of COVID-19 antivirals should be carefully scrutinized by double opinion, not only to contain health care costs but also to reduce the risk of generating resistant SARS-CoV-2 strains. Only 64.7% of patients were in fact immunized with 3+ doses of COVID-19 vaccines in the present study. High-risk patients should prioritize COVID-19 vaccination, which is a more cost-effective approach than antivirals against severe SARS-CoV-2 pneumonia. Likewise, although both antivirals, especially Nirmatrelvir/Ritonavir, were more likely than standard of care and Sotrovimab to reduce viral shedding time (VST) in high-risk SARS-CoV-2 patients, vaccination had an independent and stronger effect on viral clearance. However, the effect of antivirals or COVID-19 vaccination on VST should be considered a secondary benefit. Indeed, recommending Nirmatrelvir/Ritonavir in order to control VST in high-risk COVID-19 patients is rather questionable since other cheap, large spectrum and harmless nasal disinfectants such as hypertonic saline solutions are available on the market with proven efficacy in containing VST.

[Translated article] Paradoxical interaction between nirmatrelvir/ritonavir and voriconazole in a patient with COVID-19.

This case is based on a drug interaction between nirmatrelvir/ritonavir (approved drug for COVID-19) and voriconazole is presented, possibly derived from the bidirectional effect of ritonavir on the 2 main voriconazole metabolizing enzymes (cytochrome P450 3A and 2C19) ritonavir inhibits the former and induces the latter respectively. According to the main pharmacotherapeutic information databases, in the interaction between both drugs, a decrease in the area under the curve of voriconazole is expected due to the inducing effect of its metabolism; however, in the case we present, unexpectedly, a paradoxical effect occurs, according to what is described in literature, with the result of sustained supratherapeutic levels of voriconazole. Given the short treatment period with nirmatrelvir/ritonavir (5 days), the induction effect of ritonavir proposed in the studies on which the recommendations are based, where treatment with ritonavir is longer, does not occur.

Potential herb‒drug interactions between anti-COVID-19 drugs and traditional Chinese medicine.

Coronavirus disease 2019 (COVID-19), caused by severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2), has spread worldwide. Effective treatments against COVID-19 remain urgently in need although vaccination significantly reduces the incidence, hospitalization, and mortality. At present, antiviral drugs including Nirmatrelvir/Ritonavir (PaxlovidTM), Remdesivir, and Molnupiravir have been authorized to treat COVID-19 and become more globally available. On the other hand, traditional Chinese medicine (TCM) has been used for the treatment of epidemic diseases for a long history. Currently, various TCM formulae against COVID-19 such as Qingfei Paidu decoction, Xuanfei Baidu granule, Huashi Baidu granule, Jinhua Qinggan granule, Lianhua Qingwen capsule, and Xuebijing injection have been widely used in clinical practice in China, which may cause potential herb-drug interactions (HDIs) in patients under treatment with antiviral drugs and affect the efficacy and safety of medicines. However, information on potential HDIs between the above anti-COVID-19 drugs and TCM formulae is lacking, and thus this work seeks to summarize and highlight potential HDIs between antiviral drugs and TCM formulae against COVID-19, and especially pharmacokinetic HDIs mediated by metabolizing enzymes and/or transporters. These well-characterized HDIs could provide useful information on clinical concomitant medicine use to maximize clinical outcomes and minimize adverse and toxic effects.

Triple combination therapy with two antivirals and monoclonal antibodies for persistent or relapsed SARS-CoV-2 infection in immunocompromised patients.

INTRODUCTION: Severely immunocompromised patients are at risk for prolonged or relapsed COVID-19 leading to increased morbidity and mortality. We aimed to evaluate efficacy and safety of combination treatment in immunocompromised COVID-19 patients. METHODS: We included all immunocompromised patients with prolonged/relapsed COVID-19 treated with combination therapy with two antivirals (remdesivir plus nirmatrelvir/ritonavir, or molnupiravir in case of renal failure) plus, if available, anti-spike monoclonal antibodies (Mabs), between February and October 2022. The main outcomes were virological response at day 14 (negative SARS-CoV-2 swab) and virological and clinical response (alive, asymptomatic, with negative SARS-CoV-2 swab) at day 30 and the last follow-up. RESULTS: Overall, 22 patients (Omicron variant in 17/18) were included: 18 received full combination of two antivirals and Mabs and 4 received two antivirals only; in 20/22 (91%) two antivirals were nirmatrelvir/ritonavir plus remdesivir. Nineteen (86%) patients had hematological malignancy, 15 (68%) had received anti-CD20 therapy. All were symptomatic; 8 (36%) required oxygen. Four patients received second course of combination treatment. Response rate at day 14, 30 and last follow-up was, respectively, 75% (15/20 evaluable), 73% (16/22) and 82% (18/22). Day 14 and 30 response rates were significantly higher when combination therapy included Mabs. Higher number of vaccine doses was associated with better final outcome. Two patients (9%) developed severe side effects: bradycardia leading to remdesivir discontinuation and myocardial infarction. CONCLUSION: Combination therapy including two antivirals (mainly remdesivir and nirmatrelvir/ritonavir) and Mabs was associated with high rate of virological and clinical response in immunocompromised patients with prolonged/relapsed COVID-19.

Prevalence of inappropriate use of nirmatrelvir-ritonavir antiviral therapy in hospitalized patients: A multi-centre retrospective study in China.

BACKGROUND: Nirmatrelvir-ritonavir (NMVr) is a recently developed antiviral agent for treating coronavirus disease 2019 (COVID-19); however, data describing its appropriate use are scarce. This study examined the prevalence of inappropriate use of NMVr in a Chinese hospital setting. METHODS: A multi-centre retrospective chart review was performed for all hospitalized patients who received NMVr between 15 December 2022 and 15 February 2023 in four university-affiliated hospitals in Hangzhou, China. A multi-disciplinary team of experts developed the evaluation criteria. A group of senior clinical pharmacists examined and verified the suitability of NMVr prescriptions. RESULTS: In total, 247 patients received NMVr during the study period, of which 13.4% (n=31) met all the criteria for appropriate use of NMVr. The main types of inappropriate use of NMVr were delayed initiation of treatment (n=147, 59.5%), no dose adjustment for moderate renal impairment (n=46, 18.6%), use in patients with severe-to-critical COVID-19 (n=49, 19.8%), presence of contra-indicated drug‒drug interactions with other medications (n=36, 14.6%), and prescription for patients without a confirmed diagnosis of COVID-19 (n=36, 14.6%). CONCLUSIONS: The proportion of inappropriate use of NMVr was particularly high in the Chinese hospital setting, highlighting the urgent need to improve the appropriate use of NMVr.

Update on COVID-19 Therapy in Pediatric Age.

With the extension of the COVID-19 pandemic, the large use of COVID-19 vaccines among adults and the emergence of SARS-CoV-2 variants means that the epidemiology of COVID-19 in pediatrics, particularly among younger children, has substantially changed. The prevalence of pediatric COVID-19 significantly increased, several severe cases among children were reported, and long-COVID in pediatric age was frequently observed. The main aim of this paper is to discuss which types of treatment are presently available for pediatric patients with COVID-19, which of them are authorized for the first years of life, and which are the most important limitations of COVID-19 therapy in pediatric age. Four different antivirals, remdesivir (RVD), the combination nirmatrelvir plus ritonavir (Paxlovid), molnupiravir (MPV), and the monoclonal antibody bebtelovimab (BEB), are presently approved or authorized for emergency use for COVID-19 treatment by most of the national health authorities, although with limitations according to the clinical relevance of disease and patient's characteristics. Analyses in the literature show that MPV cannot be used in pediatric age for the risk of adverse events regarding bone growth. The other antivirals can be used, at least in older children, and RDV can be used in all children except in neonates. However, careful research on pharmacokinetic and clinical data specifically collected in neonates and children are urgently needed for the appropriate management of pediatric COVID-19.

Adverse Events of SARS-CoV-2 Therapy: A Pharmacovigilance Study of the FAERS Database.

BACKGROUND: Over the past 2 years of the several strategies recommended to help fight COVID-19, nirmatrelvir/ritonavir is a novel drug shown in the EPIC-HR phase 2 to 3 clinical trial to lower COVID-19-related death or hospitalization at day 28 when compared with placebo. OBJECTIVE: Our study's aim was to explore the reported adverse events (AEs) associated with nirmatrelvir/ritonavir use for COVID-19. METHOD: We conducted a retrospective analysis using the FDA Adverse Event Reporting System (FAERS) database for AEs, listing nirmatrelvir/ritonavir as the primary drug between January and June 2022. The primary outcome was the incidence of reported AEs associated with nirmatrelvir/ritonavir. The OpenFDA database was queried using Python 3.10 to collect the AEs and Stata 17 was used to analyze the database. Adverse events were analyzed by associated medication, with "Covid-19" excluded. RESULTS: A total of 8098 reports were identified between January and June 2022. Most reported complaints in the AE system were COVID-19 and disease recurrence. The most common symptomatic AEs were dysgeusia, diarrhea, cough, fatigue, and headache. Event rates significantly rose between April and May. Disease recurrence and dysgeusia were the most commonly reported complaints for the top 8 concomitant drugs identified. Cardiac arrest, tremor, akathisia, and death were reported in 1, 3, 67, and 5 cases, respectively. CONCLUSIONS AND RELEVANCE: This is the first retrospective study done on reported AEs associated with nirmatrelvir/ritonavir use for COVID-19. COVID-19 and disease recurrence were the most reported AEs. Further monitoring of the FAERS database is warranted to periodically reassess the safety profile of this medication.

Nirmatrelvir/ritonavir use in patients with COVID-19 on hemodialysis: a case series

Patients undergoing hemodialysis (HD) are particularly vulnerable to coronavirus disease 2019 (COVID-19) and are at increased risk of developing severe infection. However, given the exclusion of such patients from clinical trials, there are limited data regarding the effectiveness of the antiviral drug nirmatrelvir/ritonavir (N/R) in patients on HD. We prescribed N/R to four patients on HD with COVID-19 after obtaining informed consent. Their clinical symptoms were improved at approximately 3 days after N/R administration. The viral load was reduced after approximately 10 days. The main adverse effects were nausea and vomiting. Rational dosage adjustment obtained good tolerance but did not influence the efficacy. These results suggest that N/R may be a promising agent for patients on HD with COVID-19.

Nirmatrelvir/ritonavir for patients with SARS-CoV-2 infection and impaired kidney function during the Omicron surge.

Background: Nirmatrelvir/ritonavir has demonstrated effectiveness in high-risk patients with coronavirus disease 2019 (COVID-19). However, investigations on the efficacy and safety of nirmatrelvir/ritonavir in patients with kidney dysfunction are limited. Methods: Data were collected from the patients admitted to a COVID-19 referral center in Shanghai, China. Patients were at least 18 years of age and had a baseline estimated glomerular filtration rate (eGFR) of <60 ml/min/1·73 m2. The primary endpoint was a composite of all-cause mortality, intensive care unit admission, or cardiovascular events. The secondary endpoint was viral shedding. Results: Among the 195 participants, 73 received nirmatrelvir/ritonavir. A lower risk of the primary endpoint was observed in nirmatrelvir/ritonavir recipients compared with non-recipients [adjusted HR 0.56 (95% CI: 0.32-0.96); p = 0.035]. Nirmatrelvir/ritonavir recipients experienced a shorter duration of viral shedding [adjusted HR 3·70 (95%CI: 2.60-5.28); p < 0.001) and faster viral load clearance versus non-recipients. Among the nirmatrelvir/ritonavir users, earlier initiation of nirmatrelvir/ritonavir within 5 days since COVID-19 diagnosis was related with shorter viral shedding time (adjusted HR 7.84 [95% CI: 3.28-18.76]; p < 0.001) compared to late initiation. No patients reported serious adverse events during treatment. Conclusion: Our findings support the early initiation of nirmatrelvir/ritonavir for high-risk patients with impaired kidney function. This could improve patient outcomes and shorten the viral shedding period.

Nirmatrelvir-ritonavir compared with other antiviral drugs for the treatment of COVID-19 patients: A systematic review and meta-analysis.

At present, there are some differences in the research results of nirmatrelvir-ritonavir compared with other antiviral drugs for the treatment of COVID-19 patients. We aimed to evaluate the efficacy and safety of nirmatrelvir-ritonavir compared with other antiviral drugs and the impact of different antiviral drugs on the short- and long-term effects of COVID-19. PubMed, Embase, CENTRAL (Cochrane Central Register of Controlled Trials), Web of Science, Google Scholar, and MedRxiv were searched to identify relevant studies from inception to March 30, 2023. We conducted a meta-analysis to estimate the effects of nirmatrelvir-ritonavir compared with other antiviral drugs for the treatment of COVID-19 patients and safety outcomes. The RoB1 and ROBINS-I were used to assess the bias risk of the included studies. Revman 5.4 software was used for meta-analysis (PROSPERO Code No: CRD42023397816). Twelve studies were included, including 30 588 COVID-19 patients, of whom 13 402 received nirmatrelvir-ritonavir. The meta-analysis results showed that the nirmatrelvir-ritonavir group had a lower proportion of patients than the control group in terms of long-term mortality (odds ratio [OR] = 0.29, 95% confidence interval [CI]: 0.13-0.66), hospitalization (OR = 0.44, 95% CI: 0.37-0.53, short term; OR = 0.52, 95% CI: 0.36-0.77, long term), and disease progression (OR = 0.56, 95% CI: 0.38-0.83, short term; OR = 0.60, 95% CI: 0.48-0.74, long term), and nirmatrelvir ritonavir showed little difference in safety compared to the control group. Nirmatrelvir-ritonavir can reduce the mortality and hospitalization of COVID-19 patients compared with other antiviral drugs. Further large-scale studies remain to validate these findings.

Nirmatrelvir/ritonavir treatment in SARS-CoV-2 positive kidney transplant recipients - a case series with four patients.

BACKGROUND: Despite vaccination coronavirus disease 2019 (COVID-19)-associated mortality caused by severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) remains high in kidney transplant recipients. Nirmatrelvir is a protease inhibitor with activity against SARS-CoV-2. Nirmatrelvir reduces the risk for mortality and hospitalization, which is approved for treating adults at risk for severe disease. Nirmatrelvir is metabolized by the cytochrome P-450 (CYP) 3A4 isozyme CYP3A4 and is therefore co-administered with the irreversible CYP3A4 inhibitor ritonavir, which results in a drug interaction with tacrolimus. A limited number of patients with nirmatrelvir/ritonavir and tacrolimus therapy after kidney transplantation have been reported to date. It has been reported that tacrolimus was paused during the five-day nirmatrelvir/ritonavir therapy and subtherapeutic tacrolimus levels were observed after finishing nirmatrelvir/ritonavir in two patients. Therefore, optimization of tacrolimus dosing is urgently needed in transplant recipients receiving nirmatrelvir/ritonavir treatment. CASE PRESENTATION: Here, we present our first-hand experience with four patients receiving tacrolimus therapy following kidney transplantation and nirmatrelvir/ritonavir therapy due to COVID-19. Tacrolimus was paused during nirmatrelvir/ritonavir therapy in all patients, which resulted in stable therapeutic tacrolimus levels. Tacrolimus was continued directly after finishing nirmatrelvir/ritonavir to avoid subtherapeutic levels in the first patient treated. This patient received his usual tacrolimus maintenance dose, which resulted in toxic levels. Based on this observation, tacrolimus therapy was continued 24 h after finishing nirmatrelvir/ritonavir treatment at a reduced dose in the subsequent patients. In these patients, therapeutic to supratherapeutic tacrolimus levels were observed despite the therapeutic break and dose reduction. DISCUSSION AND CONCLUSIONS: Based on altered CYP3A4 metabolism, tacrolimus levels have to be closely monitored after treatment with nirmatrelvir/ritonavir. Our study suggests that tacrolimus treatment should be paused during nirmatrelvir/ritonavir medication and be continued 24 h after completing nirmatrelvir/ritonavir therapy at a reduced dose and under close monitoring. Based on the limited number of patients in this study, results must be interpreted with caution.

Real-world effectiveness of Azvudine versus nirmatrelvir-ritonavir in hospitalized patients with COVID-19: A retrospective cohort study.

Chinese guidelines prioritize the use of Azvudine and nirmatrelvir-ritonavir in COVID-19 patients. Nevertheless, the real-world effectiveness of Azvudine versus nirmatrelvir-ritonavir is still lacking, despite clinical trials showing their effectiveness compared with matched controls. To compare the effectiveness of Azvudine versus nirmatrelvir-ritonavir treatments in real-world clinical practice, we identified 2118 hospitalized COVID-19 patients, with a follow-up of up to 38 days. After exclusions and propensity score matching, we included 281 Azvudine recipients and 281 nirmatrelvir-ritonavir recipients who did not receive oxygen therapy at admission. The lower crude incidence rate of composite disease progression outcome (7.83 vs. 14.83 per 1000 person-days, p = 0.026) and all-cause death (2.05 vs. 5.78 per 1000 person-days, p = 0.052) were observed among Azvudine recipients. Azvudine was associated with lower risks of composite disease progression outcome (hazard ratio [HR]: 0.55; 95% confidence interval [CI]: 0.32-0.94) and all-cause death (HR: 0.40; 95% CI: 0.16-1.04). In subgroup analyses, the results of composite outcome retained significance among patients aged <65 years, those having a history of disease, those with severe COVID-19 at admission, and those receiving antibiotics. These findings suggest that Azvudine treatment showed effectiveness in hospitalized COVID-19 patients compared with nirmatrelvir-ritonavir in terms of composite disease progression outcome.

Possible nirmatrelvir/ritonavir-induced bradycardia in a patient with asymptomatic COVID-19.

COVID-19 emerged in 2019 and was declared a pandemic by the World Health Organization in March 2020. COVID-19 is highly transmissible and can lead to bilateral pneumonia with severe respiratory failure. COVID-19 has led to more than 6.5 million deaths worldwide. The significant morbidity and mortality due to COVID-19 have resulted in the development of treatment modalities, such as novel antivirals, to reduce hospitalizations and progression of disease. In 2021, the US Food and Drug Administration authorized nirmatrelvir/ritonavir for emergency use in nonhospitalized patients with COVID-19. Nirmatrelvir is a newly developed protease inhibitor and is combined with a commonly used pharmacokinetic boosting agent, ritonavir. Given the novelty of nirmatrelvir/ritonavir, potential adverse effects remain uncertain. In this case, we describe a patient who was initiated on a course of nirmatrelvir/ritonavir and developed symptomatic bradycardia.

Neutralizing Antibody Responses After Severe Acute Respiratory Syndrome Coronavirus 2 BA.2 and BA.2.12.1 Infection Do Not Neutralize BA.4 and BA.5 and Can Be Blunted by Nirmatrelvir/Ritonavir Treatment.

The factors contributing to the rapid emergence of severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) BA.4 and BA.5 subvariants in populations that experienced recent surges of BA.2 and BA.2.12.1 infections are not understood. Neutralizing antibodies (NAbs) are likely to protect against severe disease if present in sufficient quantity. We found that after BA.2 or BA.2.12.1 infection, NAb responses were largely cross-neutralizing but were much less effective against BA.5. In addition, individuals who were infected and treated early with nirmatrelvir/ritonavir (Paxlovid) had lower NAb levels than untreated individuals.

Prevalence of Potential Drug-drug Interactions With Ritonavir-containing COVID-19 Therapy in the United States: An Analysis of the National Health and Nutrition Examination Survey.

PURPOSE: The evolving epidemiology and treatment landscape of COVID-19 necessitates research into potential drug-drug interactions (pDDIs) from the use of new treatments for COVID-19, particularly those that contain ritonavir, a potent inhibitor of the cytochrome P350 3A4 (CYP3A4) metabolic pathway. In this study, we assessed the prevalence of pDDIs between medications for chronic conditions metabolized through the CYP3A4 metabolic pathway and ritonavir-containing COVID-19 medications in the US general population. METHODS: This study combined National Health and Nutrition Examination Survey (NHANES) waves 2015 to 2016 and 2017 to March 2020 to observe pDDI prevalence between ritonavir-containing therapy and coadministered medications among US adults 18 years or older. CYP3A4-mediated medications were identified from affirmative medication questionnaire response and associated prescription examination by surveyors. CYP3A4-mediated medications with associated pDDIs with ritonavir and assessed pDDI severity (minor, major, moderate, and severe) were obtained from the University of Liverpool's COVID-19 online drug interaction checker, Lexicomp, and US Food and Drug Administration fact sheets. pDDI prevalence and severity were evaluated by demographic characteristics and COVID-19 risk factors. FINDINGS: A total of 15,685 adult participants were identified during the 2015 to 2020 NHANES waves. Survey participants used a mean (SD) of 2.7 (1.8) drugs with likelihood of a pDDI. The weighted prevalence of major to contraindicated pDDIs among the US population was 29.3%. Prevalence rates among those 60 years and older, with serious heart conditions, with moderate chronic kidney disease (CKD), with severe CKD, with diabetes, and with HIV were 60.2%, 80.7%, 73.9%, 69.5%, 63.4%, and 68.5%, respectively. Results remained largely unchanged after removal of statins from the list of drugs associated with ritonavir-based pDDIs. IMPLICATIONS: Approximately one-third of the US population would be at risk for a major or contraindicated pDDI should they receive a ritonavir-containing regimen, and this risk increases significantly among individuals 60 years or older and with comorbidities such as serious heart conditions, CKD, diabetes, and HIV. The state of polypharmacy in the US population and the quickly changing COVID-19 landscape indicate significant risk of pDDIs among those requiring treatment with ritonavir-containing COVID-19 medications. Practitioners should take polypharmacy, age, and comorbidity profile into account when prescribing COVID-19 therapies. Alternative treatment regimens should be considered, especially for those of older age and those with risk factors for progression to severe COVID-19.