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Journal of Clinical Microbiology Feb 2021
PubMed: 33826526
DOI: 10.1128/JCM.00119-20 -
Antiviral Research Sep 2021Because ganciclovir resistance mutations in the cytomegalovirus UL97 gene most commonly occur at codons 460, 520 and 590-607, diagnostic genotyping for drug resistance...
Because ganciclovir resistance mutations in the cytomegalovirus UL97 gene most commonly occur at codons 460, 520 and 590-607, diagnostic genotyping for drug resistance has often omitted the analysis of codons below 440. However, the UL97 kinase inhibitor maribavir selects for distinctive resistance mutations at codons 409 and 411, and ganciclovir/maribavir resistance mutations have also been described in the ATP binding region starting at codon 335. Expanded genotypic testing of UL97 codons 335-440 in 1535 clinical specimens disclosed 10 uncharacterized sequence variants that were phenotyped for ganciclovir and maribavir susceptibility. Notable findings included low-grade ganciclovir resistance conferred by amino acid substitutions K359N and E362D, decreased maribavir susceptibility of L348V, and maribavir hypersensitivity of V345I and E362D. Recently published substitutions F342Y and K359E/Q were also confirmed. The data indicate that mutations in the UL97 ATP binding region may arise in clinical specimens to affect the interpretation of ganciclovir and maribavir resistance. This region should now be included in the standard diagnostic genotyping of UL97, especially with the introduction of maribavir into therapeutic use.
Topics: Adenosine Triphosphate; Amino Acid Substitution; Antiviral Agents; Benzimidazoles; Codon; Cytomegalovirus; Cytomegalovirus Infections; Drug Resistance, Viral; Ganciclovir; Genotyping Techniques; Humans; Mutation; Phenotype; Phosphotransferases (Alcohol Group Acceptor); Ribonucleosides
PubMed: 34273445
DOI: 10.1016/j.antiviral.2021.105139 -
Journal of Clinical Pharmacology Feb 2023Maribavir, an orally bioavailable antiviral, has shown superior activity against posttransplant cytomegalovirus infection compared with conventional antivirals. It is... (Randomized Controlled Trial)
Randomized Controlled Trial
Maribavir, an orally bioavailable antiviral, has shown superior activity against posttransplant cytomegalovirus infection compared with conventional antivirals. It is primarily metabolized in the liver. This open-label, single-center study evaluated the effect of hepatic impairment on the pharmacokinetics of maribavir in nontransplant participants. A single 200-mg dose of maribavir was administered orally under fasting conditions to participants with moderate hepatic impairment (Child-Pugh class B) (n = 10) and healthy controls (n = 10) matched for age, weight, sex, and smoking status. Compared with participants with normal hepatic function, maximum plasma concentration (C ) and area under the plasma concentration-time curve (AUC) from time 0 to infinity values for maribavir in participants with moderate hepatic impairment were 1.346-fold (90%CI of geometric mean ratio, 1.091-1.660) and 1.261-fold (0.889-1.787) higher, respectively. However, C and AUC values for unbound maribavir were comparable. For VP 44469, the main metabolite of maribavir, the C and AUC from time 0 to infinity values were 1.190-fold (0.836-1.693) and 1.309-fold (1.007-1.702) higher, respectively, in participants with moderate hepatic impairment. In total, 7 mild treatment-emergent adverse events were reported, all in the moderate hepatic impairment group. Dysgeusia was the most frequently reported treatment-emergent adverse event, at a frequency of 50%. These results indicated that total maribavir concentrations were mildly increased in participants with moderate hepatic impairment, while unbound concentrations were unaffected. Similar maribavir pharmacokinetics in participants with moderate hepatic impairment and normal hepatic function suggest that dose adjustment may not be required for patients with moderate hepatic impairment.
Topics: Humans; Area Under Curve; Liver Diseases; Benzimidazoles; Ribonucleosides
PubMed: 36089648
DOI: 10.1002/jcph.2155 -
Journal of Clinical Pharmacology Jan 2020Maribavir is an investigational drug being evaluated in transplant recipients with cytomegalovirus infection. To understand potential drug-drug interactions, we examined...
Maribavir is an investigational drug being evaluated in transplant recipients with cytomegalovirus infection. To understand potential drug-drug interactions, we examined the effects of multiple doses of maribavir on cytochrome P450 (CYP) 2D6 and P-glycoprotein (P-gp) activity using probe substrates in healthy volunteers. During this phase 1 open-label study (NCT02775240), participants received the probe substrates digoxin (0.5 mg) and dextromethorphan (30 mg) before and after maribavir (400 mg twice daily for 8 days). Serial plasma samples were analyzed for digoxin, dextromethorpha, dextrorphan, and maribavir concentrations. Pharmacokinetic parameters were calculated (noncompartmental analysis) and analyzed with a linear mixed-effects model for treatment comparison to estimate geometric mean ratios (GMRs) and 90% confidence intervals (CIs). CYP2D6 polymorphisms were genotyped using polymerase chain reaction. Overall, 17 of 18 participants (94.4%) completed the study. All participants were genotyped as CYP2D6 intermediate/extensive metabolizers. GMR (90%CI) of digoxin C , AUC , and AUC with and without maribavir was 1.257 (1.139-1.387), 1.187 (1.088-1.296), and 1.217 (1.110-1.335), respectively, outside the "no-effect" window (0.8-1.25). GMR (90%CI) of dextromethorphan AUC and AUC ratio of dextromethorphan/dextrorphan were 0.877 (0.692-1.112) and 0.901 (0.717-1.133), respectively, marginally outside the no-effect window, although large variability was observed in these pharmacokinetic parameters. Pharmacokinetic parameters of dextrorphan were unaffected. Maribavir inhibited P-gp activity but did not affect CYP2D6 activity. Maribavir's effect on the pharmacokinetics of P-gp substrates should be evaluated individually, and caution should be exercised with P-gp substrates with narrow therapeutic windows.
Topics: ATP Binding Cassette Transporter, Subfamily B, Member 1; Adult; Antiviral Agents; Benzimidazoles; Cytochrome P-450 CYP2D6; Cytomegalovirus Infections; Dextromethorphan; Digoxin; Drug Interactions; Female; Genotype; Healthy Volunteers; Humans; Male; Middle Aged; Ribonucleosides; Young Adult
PubMed: 31385617
DOI: 10.1002/jcph.1504 -
Viruses Jul 2023Solid organ transplant recipients (SOTRs) are at high risk of human herpesvirus (HHV)-related morbidity and mortality due to the use of immunosuppressive therapy. We aim... (Review)
Review
Solid organ transplant recipients (SOTRs) are at high risk of human herpesvirus (HHV)-related morbidity and mortality due to the use of immunosuppressive therapy. We aim to increase awareness and understanding of HHV disease burden in SOTRs by providing an overview of current prevention and management strategies as described in the literature and guidelines. We discuss challenges in both prevention and treatment as well as future perspectives.
Topics: Humans; Organ Transplantation; Herpesviridae Infections; Herpesvirus 6, Human; Herpes Simplex; Transplant Recipients
PubMed: 37515280
DOI: 10.3390/v15071595 -
The Journal of Infectious Diseases Sep 2022In separate phase 2 trials, 120 patients received maribavir for cytomegalovirus (CMV) infection failing conventional therapy (trial 202) and 119 received maribavir for...
BACKGROUND
In separate phase 2 trials, 120 patients received maribavir for cytomegalovirus (CMV) infection failing conventional therapy (trial 202) and 119 received maribavir for asymptomatic infection (trial 203). Overall, 172 cleared their CMV infection (CMV DNA <200 copies/mL) within 6 weeks.
METHODS
Baseline and posttreatment plasma samples were tested for mutations in viral genes UL97, UL54, and/or UL27. Selected viral mutants were phenotyped for drug susceptibility.
RESULTS
Baseline samples revealed UL54 mutations newly phenotyped as conferring resistance to standard DNA polymerase inhibitor(s), including K493N, P497S, K513T, L565V, V823A, A987V, and E989D. Of 29 patients (including 25 from trial 202) who cleared but later experienced recurrent CMV infection while on maribavir, 23 had available UL97 genotyping data; 17 had known resistance mutations (T409M or H411Y) and 5 additional had UL97 C480F alone. The newly phenotyped mutation C480F conferred high-grade maribavir resistance and low-grade ganciclovir resistance. Among 25 who did not respond to >14 days of therapy, 9 showed T409M or H411Y and 4 others showed C480F alone.
CONCLUSIONS
After maribavir therapy (400-1200 mg twice daily), UL97 mutations T409M, H411Y, or C480F emerge to confer maribavir resistance in patients with recurrent CMV infection while on therapy or no response to therapy.
CLINICAL TRIALS REGISTRATION
NCT01611974 and EudraCT 2010-024247-32.
Topics: Humans; Cytomegalovirus; Drug Resistance, Viral; Antiviral Agents; Phosphotransferases (Alcohol Group Acceptor); Cytomegalovirus Infections; Ganciclovir; Mutation; Phenotype
PubMed: 32726419
DOI: 10.1093/infdis/jiaa462 -
Current Infectious Disease Reports Nov 2019Transplant recipients are at risk for cytomegalovirus (CMV) infection and associated morbidity and mortality. We summarize recently introduced or currently investigated... (Review)
Review
PURPOSE OF REVIEW
Transplant recipients are at risk for cytomegalovirus (CMV) infection and associated morbidity and mortality. We summarize recently introduced or currently investigated modalities for prevention and treatment of CMV infection in hematopoietic cell (HCT) and solid organ transplant (SOT) recipients.
RECENT FINDINGS
Letermovir was recently approved for CMV prevention in HCT recipients. Data from real world studies support its role to improve outcomes in this population. Letermovir is currently under investigation for broader patient populations and indications. Maribavir is in late stages of development for CMV treatment and may provide a safer alternative to currently available anti-CMV drugs. Promising CMV vaccine candidates and adoptive cell therapy approaches are under evaluation. CMV immune monitoring assays are predicted to play a more central role in our clinical decision making. In recent years, major advances have been made in CMV prevention and treatment in transplant recipients. Rigorous research is ongoing and is anticipated to further impact our ability to improve outcomes in this population.
PubMed: 31732823
DOI: 10.1007/s11908-019-0699-0 -
Current Opinion in Organ Transplantation Apr 2024Human cytomegalovirus (CMV) continues to be the most important infectious complication following solid organ transplantation (SOT). (Review)
Review
PURPOSE OF REVIEW
Human cytomegalovirus (CMV) continues to be the most important infectious complication following solid organ transplantation (SOT).
RECENT FINDINGS
Universal prophylaxis and preemptive therapy are the most adopted strategies for prevention of CMV disease globally. Prophylaxis with valganciclovir is the most widely used approach to CMV prevention, however leukopenia and late onset CMV disease after discontinuation of prophylaxis requires new strategies to prevent this complication. The use of assays detecting CMV-specific T cell-mediated immunity may individualize the duration of antiviral prophylaxis after transplantation. Letermovir has been recently approved for prophylaxis in kidney transplant recipients. CMV-RNAemia used together with CMV-DNAemia in the viral surveillance of CMV infection provides accurate information on viral load kinetics, mostly in patients receiving letermovir prophylaxis/therapy. The development of refractory and resistant CMV infection remains a major challenge and a new treatment with maribavir is currently available. In the present paper we will review the most recent advances in prevention and treatment of CMV diseases in SOT recipients.
SUMMARY
Recent findings, summarized in the present paper, may be useful to optimize prevention and treatment of CMV infection in SOT.
Topics: Humans; Antiviral Agents; Cytomegalovirus Infections; Valganciclovir; Transplant Recipients; Organ Transplantation; Acetates; Quinazolines
PubMed: 38288947
DOI: 10.1097/MOT.0000000000001139 -
Clinical and Translational Science Nov 2020Maribavir is an orally bioavailable benzimidazole riboside in clinical development for treatment of cytomegalovirus infection in patients who undergo transplantation....
Maribavir is an orally bioavailable benzimidazole riboside in clinical development for treatment of cytomegalovirus infection in patients who undergo transplantation. Maribavir was evaluated in a thorough QT (TQT) study to determine any effects on cardiac repolarization. The effect of maribavir 100 and 1,200 mg oral doses on the baseline-adjusted and placebo-adjusted corrected QT (QTc) interval (delta delta QTc (ddQTc)) and other electrocardiogram (ECG) parameters was assessed in a randomized, phase I, placebo-controlled, four-period crossover study in healthy participants (men and women ages 18-50 years). Additionally, maribavir pharmacokinetics, safety, and tolerability were investigated. Moxifloxacin (400 mg) was used as a positive control to demonstrate the study's ability to detect QT prolongation. Digital 12-lead Holter ECG monitoring was performed over 22 hours following study drug administration. Individual, Fridericia's, and Bazett's QTc intervals were calculated. Of 52 randomized participants (29 ± 8.1 years old; 31 men (60%)), 50 (96%) completed the study. For both 100-mg and 1200-mg doses of maribavir, analysis of ddQTc demonstrated that the upper bound of the two-sided 90% confidence interval was below the 10-ms threshold at all time points. The concentration-effect analysis demonstrated no relationship between ddQTc and plasma concentrations of maribavir (and its metabolite). There were no clinically meaningful changes in heart rate and systolic blood pressure. The most common adverse event was dysgeusia; no serious adverse events were reported. This TQT study demonstrated that maribavir did not have impact on cardiac repolarization.
Topics: Administration, Oral; Adolescent; Adult; Antiviral Agents; Benzimidazoles; Blood Pressure; Cross-Over Studies; Dose-Response Relationship, Drug; Double-Blind Method; Dysgeusia; Electrocardiography; Female; Healthy Volunteers; Heart Rate; Humans; Long QT Syndrome; Male; Middle Aged; Moxifloxacin; Ribonucleosides; Young Adult
PubMed: 32506738
DOI: 10.1111/cts.12814 -
CPT: Pharmacometrics & Systems... May 2023Maribavir was approved by the US Food and Drug Administration for the treatment of patients aged ≥12 years and weighing ≥35 kg with posttransplant...
Population pharmacokinetic modeling and simulation of maribavir to support dose selection and regulatory approval in adolescents with posttransplant refractory cytomegalovirus.
Maribavir was approved by the US Food and Drug Administration for the treatment of patients aged ≥12 years and weighing ≥35 kg with posttransplant cytomegalovirus infection/disease refractory (with/without resistance) to valganciclovir, ganciclovir, cidofovir, or foscarnet, with an oral dose of 400 mg twice daily. With no pediatric clinical data available and difficulty in trial recruitment, population pharmacokinetic modeling and simulations were conducted to predict the pharmacokinetics and inform maribavir dosing in adolescents.
Topics: United States; Humans; Adolescent; Cytomegalovirus; Antiviral Agents; Ganciclovir; Cytomegalovirus Infections; Benzimidazoles; Ribonucleosides
PubMed: 36789522
DOI: 10.1002/psp4.12943