Maribavir: a new oral anti-cytomegalovirus drug

Crystal structures of pure 3-(4-bromo-2-chloro-phen-yl)-1-(pyridin-4-yl)benzo[4,5]imidazo[1,2-d][1,2,4]triazin-4(3H)-one and contaminated with 3-(4-bromo-phen-yl)-1-(pyridin-4-yl)benzo[4,5]imidazo[1,2-d][1,2,4]triazin-4(3H)-one

The side product of the cyclo-condensation reaction between ethyl benzimidazole-2-carboxyl-ate and the nitrile imine of the corresponding hydrazonyl chloride, C20H11BrClN5O, crystallized in two crystal forms. Form (1) is a co-crystal of the target compound (without any chlorine substituent) and a side product containing a Cl atom in position 2 of the bromo-phenyl group, C20H12BrN5O·0.143C20H11BrClN5O. (2) contains the pure side product. The slightly different conformation of the ring systems leads to a different packing of (1) and (2), but both crystal structures are dominated by π-π inter-actions.

1-(Pyridin-4-yl)-3-(2,4,6-trichlorophenyl)benz[4,5]imidazo[1,2-d][1,2,4]triazin-4(3H)-one

In the title compound, C20H10Cl3N5O, the 13-membered ring system makes dihedral angles of 78.64 (9)° with the trichlorophenyl ring and 62.60 (10)° with the pyridine ring. The crystal packing is dominated by π–π interactions between the 13-membered ring systems [centroid–centroid distance = 3.6655 (11)°].

CMV: Prevention, Diagnosis and Therapy

Cytomegalovirus (CMV) is the most common infection after organ transplantation and has a major impact on morbidity, mortality and graft survival. Optimal prevention, diagnosis and treatment of active CMV infection enhance transplant outcomes, and are the focus of this section. Methods to prevent CMV include universal prophylaxis and preemptive therapy; each has its merits, and will be compared and contrasted. Diagnostics have improved substantially in recent years, both in type and quality, allowing for more accurate and savvy treatment; advances in diagnostics include the development of an international standard, which should allow comparison of results across different methodologies, and assays for cellular immune function against CMV. Therapy primarily involves ganciclovir, now rendered more versatile by data suggesting oral therapy with valganciclovir is not inferior to intravenous therapy with ganciclovir. Treatment of resistant virus remains problematic, but is enhanced by the availability of multiple novel therapeutic agents.

International consensus guidelines on the management of cytomegalovirus in solid organ transplantation

Cytomegalovirus (CMV) remains one of the most common infections after solid organ transplantation, resulting in significant morbidity, graft loss, and occasional mortality. Management of CMV varies considerably among transplant centers. A panel of experts on CMV and solid organ transplant was convened by The Infectious Diseases Section of The Transplantation Society to develop evidence and expert opinion-based consensus guidelines on CMV management including diagnostics, immunology, prevention, treatment, drug resistance, and pediatric issues.

A randomized, double-blind, pharmacokinetic study of oral maribavir with tacrolimus in stable renal transplant recipients

Maribavir is being developed as a novel agent for the prevention or treatment of cytomegalovirus infections after stem cell and organ transplantation. This was a randomized, double-blind, placebo-controlled study designed to evaluate the potential pharmacokinetic interaction of concomitant administration of maribavir and tacrolimus. Twenty-five adult renal transplant recipients with stable renal function and stable dosing regimens of tacrolimus were randomized (20 maribavir 400 mg p.o. q12 h: 5 placebo). Tacrolimus whole blood concentration profiles were determined before and after 7 days of co-administration with maribavir. When co-administered with maribavir, tacrolimus mean C(max) increased 38%, tacrolimus trough concentrations (12 h post-dose) increased 57% and tacrolimus AUC((0-tau)) increased 51%. Apparent oral clearance of tacrolimus decreased 34% and T(max) was delayed by 0.5 h. There were no serious adverse events and no subject prematurely discontinued treatment. Because of the limited 7-day dosing course, the adverse event profile could not be adequately assessed. However, as seen with other maribavir studies, dysgeusia was common (90% of maribavir subjects and 20% of placebo subjects). In conclusion, co-administration of maribavir 400 mg twice daily increases exposure to tacrolimus. Routine therapeutic drug monitoring of tacrolimus blood concentrations should be included both at initiation and completion of maribavir treatment.