Pharmacokinetics of Lopinavir and Ritonavir in Patients Hospitalized With Coronavirus Disease 2019 (COVID-19).

Abstract

Letters20 October 2020Pharmacokinetics of Lopinavir and Ritonavir in Patients Hospitalized With Coronavirus Disease 2019 (COVID-19)FREEChristian Schoergenhofer, MD, PhD, Bernd Jilma, MD, Thomas Stimpfl, PhD, Mario Karolyi, MD, and Alexander Zoufaly, MDChristian Schoergenhofer, MD, PhDMedical University of Vienna, Vienna, Austria (C.S., B.J., T.S.)Search for more papers by this author, Bernd Jilma, MDMedical University of Vienna, Vienna, Austria (C.S., B.J., T.S.)Search for more papers by this author, Thomas Stimpfl, PhDMedical University of Vienna, Vienna, Austria (C.S., B.J., T.S.)Search for more papers by this author, Mario Karolyi, MDKaiser-Franz-Josef-Hospital, Vienna, Austria (M.K., A.Z.)Search for more papers by this author, and Alexander Zoufaly, MDKaiser-Franz-Josef-Hospital, Vienna, Austria (M.K., A.Z.)Search for more papers by this authorAuthor, Article, and Disclosure Informationhttps://doi.org/10.7326/M20-1550 SectionsAboutVisual AbstractPDF ToolsAdd to favoritesDownload CitationsTrack CitationsPermissions ShareFacebookTwitterLinkedInRedditEmail Background: The coronavirus disease 2019 (COVID-19) pandemic has rapidly spread around the world, and the lack of effective treatment has fueled a global search for the “magic bullet” against the disease caused by severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2). As of 29 April 2020, a total of 997 COVID-19 trials were registered at ClinicalTrials.gov, of which more than 30 are investigating the effects of lopinavir and ritonavir.Lopinavir is the main antiviral agent, whereas ritonavir acts as a pharmacokinetic “booster” that increases lopinavir plasma concentrations by inhibiting cytochrome 3A4 enzymes (1). The combination is an approved antiretroviral therapy for adults with HIV-1 infection. However, in vitro data also suggest antiviral activity of lopinavir against SARS-CoV-1, with a half-maximal effective concentration (EC50) of 4.1 µg/mL; Middle East respiratory syndrome-CoV, with an EC50 of 10.8 µg/mL; and, only recently, SARS-CoV-2, with an EC50 of 16.4 µg/mL (2). Importantly, the EC50 for HIV-1 is 0.07 µg/mL, more than 200-fold lower than for SARS-CoV-2 (1). Recently, Cao and colleagues published negative results of a placebo-controlled trial in patients hospitalized with COVID-19 in which lopinavir treatment did not affect mortality, clinical performance, or viral loads (3).Objective: To measure trough levels of lopinavir and ritonavir in patients with COVID-19.Methods and Findings: In this series of 8 patients who were admitted to a “normal care” ward because of COVID-19, we quantified trough plasma concentrations of lopinavir and ritonavir by liquid chromatography–tandem mass spectrometry. Patients with concomitant intake of relevant CYP3A4 inducers or inhibitors were excluded. Patients were hospitalized and received 400 mg of lopinavir and 100 mg of ritonavir twice daily for 3 to 10 days before analysis, which was done in the morning shortly before the next dose. Assuming a half-life of 4 to 6 hours for lopinavir, steady-state conditions may be assumed for all patients. Analysis of trough levels was chosen because they provide more robust pharmacokinetic information for single time–point assessments and were frequently investigated in HIV trials, which makes the data comparable.Trough concentrations of lopinavir ranged from 6.2 to 24.3 µg/mL (median, 13.6 µg/mL) (Table). Interestingly, in this small sample, trough concentrations seemed to be associated with C-reactive protein (Spearman correlation coefficient rS = 0.81). All patients had an unremarkable disease course and were discharged from the normal care ward. Specific adverse effects of lopinavir and ritonavir were not observed.Table. Lopinavir and Ritonavir Trough Concentrations in Patients Hospitalized With COVID-19Discussion: We report the first pharmacokinetic data of lopinavir and ritonavir in patients hospitalized with COVID-19. Lopinavir trough levels were approximately 2-fold higher in our population than in patients with HIV receiving the same dose (7.1 µg/mL) (1). This may have been caused by inflammation-induced downregulation of cytochrome P450 enzyme activity and reduced drug metabolism, which is mediated by proinflammatory cytokines, including interleukin (IL)-1, IL-6, and tumor necrosis factor-α (4). The observed correlation of drug concentrations with C-reactive protein, a downstream marker of IL-6, supports this hypothesis and is notable because C-reactive protein levels were not exceedingly high in our population. High levels of IL-6 are associated with disease severity (5), and IL-6–blocking therapies are being investigated in several clinical trials. Thus, drug metabolism may be even more impaired in more severe cases of COVID-19. Furthermore, clinicians should be aware that anti-inflammatory treatments may severely affect the pharmacokinetics of cytochrome enzyme–dependent drugs.This analysis has limitations. Only trough levels were quantified, and more detailed pharmacokinetics were not available. Also, there are no data on the half-maximal effective dose of lopinavir for SARS-CoV-2 in vivo.Currently, more than 30 trials of lopinavir and ritonavir treatment of COVID-19 are registered, and according to ClinicalTrials.gov, doses range from 200 to 400 mg of lopinavir and from 50 to 100 mg of ritonavir twice daily (the patients in our analysis received the latter dose for each drug). Unfortunately, lopinavir is almost completely bound by plasma proteins, and only 1% to 2% are free and active (1). To translate drug concentrations in vitro to unbound (and therefore active) concentrations in vivo, a correction for protein binding is required (1, 2). Unbound drug concentrations of lopinavir are far from reaching the EC50 of SARS-CoV-2 (16.4 µg/mL), although they clearly suffice to inhibit HIV-1.In conclusion, despite the approximately 2-fold higher lopinavir trough concentrations in our sample of patients with COVID-19 compared with patients with HIV, approximately 60- to 120-fold higher concentrations are required to reach the assumed EC50 at trough levels, making effective treatment of COVID-19 with lopinavir and ritonavir at the currently used doses unlikely.References1. Croxtall JD, Perry CM. Lopinavir/ritonavir: a review of its use in the management of HIV-1 infection. Drugs. 2010;70:1885-915. [PMID: 20836579] doi:10.2165/11204950-000000000-00000 CrossrefMedlineGoogle Scholar2. Choy KT, Wong AY, Kaewpreedee P, et al. Remdesivir, lopinavir, emetine, and homoharringtonine inhibit SARS-CoV-2 replication in vitro. Antiviral Res. 2020;178:104786. [PMID: 32251767] doi:10.1016/j.antiviral.2020.104786 CrossrefMedlineGoogle Scholar3. Cao B, Wang Y, Wen D, et al. A trial of lopinavir-ritonavir in adults hospitalized with severe Covid-19. N Engl J Med. 2020;382:1787-1799. [PMID: 32187464] doi:10.1056/NEJMoa2001282 CrossrefMedlineGoogle Scholar4. Schoergenhofer C, Hobl EL, Schellongowski P, et al. Clopidogrel in critically ill patients. Clin Pharmacol Ther. 2018;103:217-223. [PMID: 28913918] doi:10.1002/cpt.878 CrossrefMedlineGoogle Scholar5. Liu F, Li L, Xu M, et al. Prognostic value of interleukin-6, C-reactive protein, and procalcitonin in patients with COVID-19. J Clin Virol. 2020;127:104370. [PMID: 32344321] doi:10.1016/j.jcv.2020.104370 CrossrefMedlineGoogle Scholar Comments0 CommentsSign In to Submit A Comment Stephanie RUIZ(1), Didier CONCORDET(2), Sarah BAKLOUTI(3), Jean-Marie CONIL(1), Peggy GANDIA(2-3)1: Service de Réanimation, CHU de Toulouse, France ; 2: INTHERES, INRA ENVT, Toulouse, France; 3: Laboratoire de Pharmacocinétique et Toxicologie, CHU de Toulouse, France27 May 2020 Lopinavir in COVID-19 patients: an examination of lung exposure Due to the lack of information on lopinavir exposure in COVID-19 patients, total plasma concentrations (i.e. the sum of free and bound lopinavir to plasma proteins) were monitored in many European countries. Trough total concentrations (i.e. the value measured on a blood sample collected just before drug administration) are 3 to 4 times higher than the values reported in HIV patients treated with the same dosage regimen (1, 2), suggesting over-exposure in COVID-19 patients. These values have prompted clinicians to reduce the dose or even stop treatment. Unfortunately, using total concentration as a marker of exposure for highly bound drugs is a well-known pharmacokinetic mistake (3), repeated once again for COVID-19 patients. Lopinavir is highly bound to plasma proteins (>98%), mainly to α1 acid glycoprotein (AAG) and to a lesser extent to albumin (1). Since AAG concentrations are highly elevated during acute inflammation in COVID-19 patients, higher bound and total lopinavir exposure are expected while unbound exposure remains unchanged (4). Therefore, measuring unbound lopinavir concentrations is critical for drug dosage adjustment. On the other hand, the crucial information remains the drug concentration at the infectious site (i.e. the lung). Unfortunately, this information is not available. A lung biopsy would appear to be the most informative approach. However, in such fragile and unstable patients, this option would be highly intrusive. An alternative approach is to evaluate lopinavir concentration in the lung epithelial lining fluid (ELF). This information was available for two critically ill COVID-19 patients from Toulouse University Hospital (France) (60 and 64 years old, BMI at 36 and 20, and SAPS II at 43 and 38 respectively). They presented severe ARDS and were intubated. The ELF (0.47; 3.88 mg/l) and plasma concentrations (8.86; 7.75 mg/l) were available 15 and 8 days after the treatment initiation, with a ratio of 0.05 and 0.5 respectively. In both cases, ELF values were lower than the EC50 (26 µM or 16.3 mg/l) reported for SARS-CoV-2 (4). Even if our data are very sparse, they could help to explain the failure of lopinavir to reduce the SARS-CoV2 viral load as already discussed (5) and suggest that increasing the lopinavir dose to reach effective lung concentrations is necessary but at the cost of more side effects. 1. Boffito M, Hoggard P, Lindup W. 2004. Lopinavir Protein Binding In Vivo Through the 12-Hour Dosing Interval. Ther Drug Monit 26:35–39. 2. Gregoire M, Le Turnier P, Gaborit BJ, Veyrac G, Lecomte R, Boutoille D, Canet E, Imbert B-M, Bellouard R, Raffi F. 2020. Lopinavir pharmacokinetics in COVID-19 patients. J Antimicrob Chemother. 3. Rolan PE. 1994. Plasma protein binding displacement interactions--why are they still regarded as clinically important? Br J Clin Pharmacol 37:125–128. 4. Choy K-T, Wong AY-L, Kaewpreedee P, Sia SF, Chen D, Hui KPY, Chu DKW, Chan MCW, Cheung PP-H, Huang X, Peiris M, Yen H-L. 2020. Remdesivir, lopinavir, emetine, and homoharringtonine inhibit SARS-CoV-2 replication in vitro. Antiviral Res 178:104786. 5. Cao B, Wang Y, Wen D. 2020. A Trial of Lopinavir-Ritonavir in Adults Hospitalized with Severe Covid-19. N Engl J Med. Christian Schoergenhofer, MD, PhD1, Bernd Jilma, MD1, Thomas Stimpfl, PhD2, Mario Karolyi, MD3 and Alexander Zoufaly, MD31 Department of Clinical Pharmacology, Medical University of Vienna 2 Clinical Department of Laboratory Medicine, Medical University of Vienna 3 Department of Medicine 4, Kaiser-Franz-Josef-Hospital,2 June 2020 Authors' Response We fully agree that (i) protein binding must be taken into account and (ii) drug concentrations at the infectious site (e.g. in the lungs) are more relevant than plasma concentrations, because after all it is where antimicrobial substances have to fight infections. Thus, we appreciate that the authors shared their interesting data which confirm the lopinavir plasma concentrations found in our patients (1), but also demonstrating lopinavir concentrations in epithelial lining fluid (ELF). These data, support our conclusion that lopinavir concentrations are far from reaching effective concentrations to conquer SARS-COV-2. However, ELF drug concentrations should only be interpreted with caution, because of well-known methodological issues (2). To interpret any concentrations in ELF its concentration in bronchoalveolar lavage (BAL) fluid has to be calculated. This is mostly done by quantification of urea, because it is a small, non-polar molecule which can diffuse freely across membranes. The concentration of urea is therefore assumed to be equal in plasma and in ELF, while the instilled fluid during BAL is free of urea (3), so that the dilution may easily be calculated. However, it is important to note that this method is frequently inaccurate, because urea concentrations in BAL may be affected by various factors including the “dwelling time”, during which urea may diffuse into the instilled fluid (3). Thus, ELF volume is frequently overestimated. Also drug concentrations may be over-estimated by intracellular drug contents of lysed cells. Moreover, the protein concentration in ELF needs to be considered, which may vary substantially depending on vascular permeability and the local or systemic inflammatory response (3). Total protein concentrations in ELF are much lower compared to whole blood, but may increase significantly during inflammation (3, 4) and manifold in pneumonia (5). Thus, the degree of protein binding in ELF (or lung tissue) is difficult to estimate, but also has to be considered to draw any definitive conclusions. Possibly further validation of analytical methods may also be necessary. Importantly, the median trough plasma concentrations of lopinavir of 13.6µg/mL, and for that matter also the presented ELF drug concentrations, are below the EC50 for SARS-COV-2 even without adjustment for protein binding. Hence, based on these considerations effective treatment of COVID-19 with lopinavir at the currently used doses seems highly unlikely.