Cytomegalovirus Antiviral Resistance Among Kidney Transplant Recipients in a Phase 3 Trial of Letermovir vs Valganciclovir Prophylaxis.

Background: In a phase 3 trial, letermovir was noninferior to valganciclovir for cytomegalovirus (CMV) disease prophylaxis in kidney transplant recipients who were CMV-seronegative and received kidneys from donors who were CMV-seropositive. Genotypic antiviral resistance and CMV glycoprotein B (gB) genotype are reported.

Methods: Plasma samples with detectable CMV DNA were sequenced for the presence of known letermovir and valganciclovir resistance-associated amino acid substitutions (RASs) encoded by CMV gene regions (UL51, UL54, UL56, UL89, UL97) and prevalence of gB (UL55) genotypes (gB1-gB5).

Molnupiravir: Mechanism of action, clinical, and translational science.

Molnupiravir is an oral prodrug of the broadly active, antiviral ribonucleoside analog N-hydroxycytidine (NHC). The primary circulating metabolite NHC is taken up into cells and phosphorylated to NHC-triphosphate (NHC-TP). NHC-TP serves as a competitive substrate for viral RNA-dependent RNA polymerase (RdRp), which results in an accumulation of errors in the viral genome, rendering virus replication incompetent.

Respiratory virus coinfections during the COVID-19 pandemic: epidemiologic analysis and clinical outcomes from the Phase 2/3 molnupiravir trial (MOVe-OUT).

Unlabelled: This exploratory analysis assessed the incidence of respiratory viral coinfections and their impact on clinical outcomes in non-hospitalized adults with mild-to-moderate coronavirus disease-2019 (COVID-19) treated with molnupiravir versus placebo for 5 days in the Phase 2/3 MOVe-OUT trial (NCT04575597), which took place in October 2020 to January 2021 (Phase 2, = 302) and May 2021 to October 2021 (Phase 3, = 1,433). Among 1,735 total randomized participants, 1,674 had a baseline respiratory pathogen panel (NxTAG Respiratory Pathogen Panel for the Luminex MAGPIX instrument) performed and 69 (4.1%) were coinfected with at least one additional respiratory viral pathogen.

Molnupiravir maintains antiviral activity against SARS-CoV-2 variants and exhibits a high barrier to the development of resistance.

Molnupiravir, an oral prodrug of N-hydroxycytidine (NHC), previously demonstrated broad antiviral activity against multiple RNA viruses and has shown a high barrier to the development of resistance. Here, we present the antiviral activity of NHC against recent SARS-CoV-2 variants and the results of resistance selection studies to better understand the potential for viral resistance to NHC. NHC activity against SARS-CoV-2 variants omicron (BA.