BACKGROUND:Ganciclovir remains the primary therapeutic for cytomegalovirus (CMV) infections in early infancy, but its pharmacokinetics and dosing in very preterm infants with end-organ CMV disease have not been fully evaluated. METHODS:Premature infants with confirmed CMV infection and receiving ganciclovir as standard of care were enrolled into a pharmacokinetic (PK) sampling study. All infants were <32 weeks gestational age and >500 g at enrollment. Plasma for ganciclovir quantitation was collected at steady state at 0, 1, 2-3, 5-7, and 10-12 hours after the dose. Specimens were shipped and analyzed, and PK parameters were calculated in real time. Noncompartmental and modeling approaches were used for analysis. RESULTS:Eighteen infants were enrolled; their mean gestational age at delivery was 26.7 weeks, and their mean age and weight at enrollment were 42 days and 1519.0 g, respectively. PK assessments were completed in 17. The geometric mean dose and resulting 12-hour area under the curve were 5.19 mg/kg and 52.7 mg · h/L, respectively. A total of 85 ganciclovir concentration-time data points were available for modeling. A 1-compartment power covariate model with weight and serum creatinine on clearance and weight on distribution volume was used. Noncompartmental and modeled PK parameters were similar. CONCLUSIONS:These are the first intravenous ganciclovir population PK data with covariate assessments in premature infants being treated for CMV disease. Results suggest an intravenous dose of 5 mg/kg every 12 hours may be an appropriate starting regimen in of premature infants with congenital CMV. Additional data are needed in this and other populations to better define optimal ganciclovir exposure targets.

Background: Long COVID, the chronic sequela of SARS-CoV-2 infection, has affected millions of people worldwide. However, its pathogenesis and treatment remain unknown. To address this critical gap, the National Institutes of Health (NIH) developed the Researching COVID to Enhance Recovery (RECOVER) Initiative that included the Viral Persistence and Reactivation, and Immune Dysregulation (RECOVER-VITAL) study as one of the first of five NIH-sponsored, integrated platform protocols to support the rigorous and rapid investigation of potential interventions for Long COVID. Methods: Experts across academia, the NIH, and the community of patients and caregivers were brought together to design the RECOVER-VITAL protocol. We present the challenges and rationale underpinning critical components of this protocol and provide evidence for use of the platform for efficient execution of current and future Long COVID clinical trials. Facets of the RECOVER-VITAL protocol, including inclusion criteria, intervention groups, study procedures, investigation of biomarkers, and endpoints, were carefully crafted to advance the current and future science and operations of Long COVID clinical trials, particularly in the absence of existing data. The initial trial within the RECOVER-VITAL platform evaluated two durations of an antiviral drug, nirmatrelvir/ritonavir, to test the proposed etiology of viral persistence on the Long COVID symptom clusters of autonomic dysfunction, cognitive dysfunction, and exercise intolerance. The primary outcome measures were patient-reported, and secondary outcomes included performance-based measures for each of the symptom clusters of interest. Conclusions: The RECOVER-VITAL platform protocol has substantial implications for the design and conduct of future Long COVID clinical trials.

Toxicity from IVT oHSV in the left lateral ventricle and third and fourth ventricles at different time points.

This supplement contains 17 articles addressing various aspects of advances in influenza therapeutics and related strategies (e.g., diagnostics, rapid access strategies, and resistance monitoring) for preventing and treating seasonal, zoonotic, and pandemic influenza. In addition to briefly introducing each article, we highlight shortcomings in current use, knowledge gaps requiring further study, and therapeutics of interest entering or advancing in clinical development.

A highly sensitive cell-based imaging assay has been used to screen a 200,000 compounds library for potential influenza antivirals. Compounds were screened at a concentration of 10 μM against the influenza strain A/Udorn/72 (H3N2) and the duplex capability of the assay was taken advantage of to select compounds with no or low cytotoxicity. The assay was also used for confirmation in concentration-response of the active compounds. In the set of confirmed hits, three major structural clusters, 23 minor clusters and 86 singletons were identified. Further evaluation of anti-influenza activity was performed for two additional influenza strains of the H1N1 subtype, A/WSN/33 and A/California/07/09. Three compounds from cluster A, SRI-44211, SRI-44215 and SRI-44221 showed selectivity indices for the pandemic strain A/California/07/09 in the range of 54.3-252, providing evidence that the core structure of cluster A could play a relevant role in their inhibitory potency and may serve as a starting point for future hit-to-lead optimization efforts.

BACKGROUND:Decreasing the length of hospitalization for an infant with neonatal Herpes simplex virus (HSV) disease could potentially reduce the emotional stress and demands on families and the financial burden on healthcare systems. However, home parenteral acyclovir administration is difficult, and oral acyclovir has reduced bioavailability. Valacyclovir has favorable bioavailability in older children and adults and could be considered for use in a portion of the treatment course. METHODS:Seven infants with neonatal HSV disease were treated with parenteral acyclovir. At the completion of their 14- or 21-day course of parenteral acyclovir, they were switched to valacyclovir suspension 20 mg/kg/dose every 8 hours for at least 2 days before starting oral acyclovir suppressive therapy. While receiving parenteral acyclovir and oral valacyclovir, pharmacokinetic sampling profiles were obtained. RESULTS:Following parenteral acyclovir administration, clearance, volume, half-life and area under the curve from zero to infinity were (mean ± SD): 1.1±0.4 L/h, 3.6 ± 2.0 L, 2.5 ± 1.3 hours and 70.1 ± 41.0 mg h/L. Following valacyclovir administration, oral clearance, apparent distribution volume, absorption rate constant, half-life and area under the curve from zero to infinity were: 3.1 ± 1.8 L/h, 12.3 ± 9.9 L, 3.4 ± 3.1/h, 2.7 ± 1.2 hours and 28.8 ± 16.8 mg h/L. Valacyclovir's estimated mean bioavailability was 38.7%. CONCLUSION:The bioavailability of valacyclovir was lower than that seen in older infants and adults, and the systemic acyclovir exposure following valacyclovir (28.8 mg h/L) was 2.4 times lower than that of parental acyclovir (70.1 mg h/L). Therefore, valacyclovir suspension at the studied dose of 20 mg/kg/dose every 8 hours cannot be recommended for use in a portion of the treatment course for neonatal HSV disease.

Comparison of the protective effect of different pretreatment low doses of IVT oHSV from toxicity after a subsequent treatment dose.

IHC staining of the ependymal lining for CD8+ cells and confirmation of CD8 depletion.

We report the synthesis and evaluation of novel prodrugs of 6-azacytidine (6-AzaCyd) to identify potent and bioavailable inhibitors of influenza A viruses. Prodrug N4-2-propylpentanamide 6-AzaCyd 6a was identified, through a nucleoside prodrug strategy, with a promising potency profile [H1N1-EC90 = 2.6 μM, VTR = 3 at 10 μM; H3N2-EC90 = 3.5 μM, VTR = 2.8 at 10 μM in MDCK cells; EC50 = 2.1 μM from cap snatching polymerase U2-PB2 assay; cytotoxicity CC50 > 40 μM in A549 cells; CC50 > 20 μM in MDCK cells] and an acceptable absorption, distribution, metabolism and excretion (ADME) profile [mouse liver microsome (MLM) t1/2 = 105 min, human liver microsome (HLM) t1/2 = 65 min, Solubility = 77 μM]. Compound 6a also exhibited acceptable pharmacokinetic properties via intraperitoneal (i.p.) route of administration. The details for the synthesis of 6-AzaCyd prodrugs and anti-influenza A activity are described herein.

Body weights of CBA/J, BALB/c and C57BL/6 mice (N = 5/group) after inoculation with 1x107 PFU of IVT oHSV.

Toxicity with repeated doses of IVT oHSV.

Effects of poly I:C alone and combined with oHSV in vitro and in vivo.

Time to recover baseline body weight in mice pretreated with low-dose oHSV prior to a standard treatment dose.

Interferon β (IFN β) levels over time in the CSF after a single 50 µg IVT dose of poly I:C or saline (N = 2 mice/group/time point).

BACKGROUND:BK polyomavirus (BKV) can cause permanent loss of allograft function due to BKV-associated nephropathy (BKVN) in kidney transplant recipients. Besides immunosuppression reduction, there are no consistently effective interventions for BKV infection. Study purpose was to define natural history of BKV infection, identify risk factors for BKV reactivation and BKVN in kidney transplant recipients, and inform the design/conduct of future clinical trials of BKV-targeted therapeutics. METHODS:We conducted a multicenter prospective observational study of incident kidney transplant recipients at six U.S. transplant centers. Participants were monitored every 4 weeks for BKV reactivation and followed for up to 24 months post-transplant. We used regression models (logistic, survival, mixed models) to study relationships between BK viremia/BKVN, clinical characteristics, and allograft function. RESULTS:We enrolled 335 participants. Fifty-eight (17%) developed BK viremia, 6 (2%) developed biopsy-proven BKVN, and 29 (9%) developed suspected/presumed BKVN (defined as BKV viral load > 10,000 copies/mL without biopsy). Male donor sex was associated with lower odds for BK viremia, whereas recipient Black race was associated with two-fold increased odds for BK viremia. Recipient female sex was associated with more rapid clearance of BK viremia. Persistent BK viremia/BKVN was associated with poorer allograft function by 24 months post-transplant. CONCLUSIONS:We identified multiple donor and recipient demographic factors associated with risk for BKV infection and poorer allograft function by 24 months post-transplant. This may help design future clinical trials of therapies to prevent or mitigate the deleterious impact of BKV reactivation on kidney transplant outcomes.

Congenital cytomegalovirus (CMV) and herpes simplex virus (HSV) infections are among the most common viral infections of the newborn in the developed world. CMV infections can cause sensorineural hearing loss, and both CMV and HSV infections can lead to impaired neurodevelopment. Diagnostic and treatment efforts have been investigated for the past 45 years. With the development of polymerase chain reaction (PCR) for diagnosis and its quantitation as well as studies of the pharmacokinetics and pharmacodynamics of ganciclovir/valganciclovir (CMV) and acyclovir (HSV), significant improvement in outcome has been achieved. For example, studies utilizing ganciclovir and valganciclovir demonstrate improved hearing and Bailey Developmental scores; however, therapy requires six months of treatment with valganciclovir. With neonatal HSV infections, high-dose acyclovir decreases mortality for two classifications of disease - encephalitis and disseminated multiorgan infection. Like congenital CMV infections, neonatal HSV requires long-term suppressive therapy following a course of IV acyclovir. Regardless, outcome for both diseases is unsatisfactory, and improved treatment approaches must be developed. The current review addresses these two members of the Herpesviridae family: the diseases they cause in the newborn, the current shortcomings and a consideration of future needs. Both viruses establish latency and are reactivated throughout an individual’s lifetime, ergo eradication at the present is impossible. The discussion is limited to these two life-threatening diseases. The successful lessons learned from combination therapies of human immunodeficiency virus and hepatitis C virus infections must be applied to these diseases. If improvement can be documented, it will have direct implications for managing diseases caused by both viruses in older individuals. It is the aim of the review to provide the reader with knowledge of the field, providing a reference to future needs and opportunities.

Although neonates are commonly exposed to vaginal herpes simplex virus (HSV)-2, neonatal herpes is rare. Therefore, we analyzed paired infant and maternal HSV-2 isolates from two cases of mother-to-infant transmission to identify viral factors contributing to vertical transmission. Sixteen infant isolates with neonatal herpes and 27 genital isolates in their third trimester were included. The infant isolates were significantly more temperature-independent than the maternal isolates. Sequence comparison revealed viral UL13 protein kinase (UL13-PK) mutation in the infant isolates in both cases. In the expanded cohort, infant isolates (5/18) had significantly more UL13-PK mutations than genital isolates (1/29). Isolates within 8 days post-birth (3/4) had a significantly higher frequency of UL13-PK mutation than those after 9 days (2/14), suggesting a close association between UL13-PK mutations and vertical transmission. Elongation factor 1-delta was identified as a target of UL13-PK by proteomic analysis of UL13-PK-positive and -negative HepG2 cells. The mixed infant isolates with the intact and mutated UL13-PK conferred altered cell tropism, temperature independence adapting to fetal temperature, and better growth properties in Vero and hepatoblastoma HepG2 cells than in HSV-2 with intact and mutated UL13-PK alone, indicating that viral UL13-PK mutation is essential for vertical HSV-2 transmission.

BACKGROUND:BK polyomavirus-associated nephropathy (BKPyVAN) is an important cause of allograft dysfunction and failure in kidney transplant recipients (KTRs) and there are no proven effective treatments. Case reports and in vitro data support the potential activity of cidofovir against BK polyomavirus (BKPyV). METHODS:We report the results of a phase I/II, double-blind, placebo-controlled randomized dose-escalation trial of cidofovir in KTRs with biopsy-confirmed BKPyVAN and estimated glomerular filtration rate ≥30 mL/min. Intravenous cidofovir (0.25 mg/kg/dose or 0.5 mg/kg/dose) or placebo was administered on days 0, 7, 21, and 35, with final follow-up through day 49. RESULTS:The trial was prematurely discontinued due to slow accrual after 22 KTRs had completed the study. Cidofovir was safe and tolerated at the doses and duration studied. The proportion of subjects with any adverse event (AE) was similar between groups (9/14 [64%] in the combined cidofovir dose groups and 6/8 [75%] in the placebo group); 84% of AEs were mild. BKPyV DNAemia reduction by day 49 was similar between groups (>1 log10 reduction in (2/9 [22.2%] of 0.25 mg/kg group, 1/5 [20%] of 0.5 mg/kg group, and 2/8 [25%] of placebo group). CONCLUSIONS:These preliminary results indicate that low-dose cidofovir was safe and tolerated but had no significant BKPyV-specific antiviral effect in KTRs with BKPyVAN.

OBJECTIVE:The objective of this study was to determine if valganciclovir initiated after 1 month of age improves congenital cytomegalovirus-associated sensorineural hearing loss. STUDY DESIGN:We conducted a randomized, double-blind, placebo-controlled phase 2 trial of 6 weeks of oral valganciclovir at US (n = 12) and UK (n = 9) sites. Patients of ages 1 month through 3 years with baseline sensorineural hearing loss were enrolled. The primary outcome was change in total ear hearing between baseline and study month 6. Secondary outcome measures included change in best ear hearing and reduction in cytomegalovirus viral load in blood, saliva, and urine. RESULTS:Of 54 participants enrolled, 35 were documented to have congenital cytomegalovirus infection and were randomized (active group: 17; placebo group: 18). Mean age at enrollment was 17.8 ± 15.8 months (valganciclovir) vs 19.5 ± 13.1 months (placebo). Twenty (76.9%) of the 26 ears from subjects in the active treatment group did not have worsening of hearing, compared with 27 (96.4%) of 28 ears from subjects in the placebo group (P = .09). All other comparisons of total ear or best ear hearing outcomes were also not statistically significant. Saliva and urine viral loads decreased significantly in the valganciclovir group but did not correlate with change in hearing outcome. CONCLUSIONS:In this randomized controlled trial, initiation of antiviral therapy beyond the first month of age did not improve hearing outcomes in children with congenital cytomegalovirus-associated sensorineural hearing loss. CLINICAL TRIAL REGISTRATION:ClinicalTrials.gov identifier NCT01649869.