Varicella-Zoster Virus Reactivation and Increased Vascular Risk in People Living with HIV: Data from a Retrospective Cohort Study

BACKGROUND

The increased vascular risk associated with varicella-zoster virus (VZV) reactivation is extensively established in the general population. This retrospective cohort study investigates whether this observation holds for People Living with HIV (PLWH), a group already confronting heightened cardiovascular risk.

METHODS

Among PLWH who initiated antiretroviral therapy (ART) at our center and have been under our care for >24 months since 1st January 2005, individuals with a history of herpes zoster (HZ) were identified, and their features were compared with those of PLWH with no history of HZ. The prevalence of ischemic events (deep venous thrombosis, stroke, and acute myocardial infarction) was calculated and compared using the chi-square test. An odds ratio (O.R.) and a 95% confidence interval (C.I.) for ischemic events following HZ were evaluated through univariate and multivariate logistic regression.

RESULTS

Overall, 45/581 PLWH reported HZ. Ischemic events followed HZ significantly more often than not (13% vs. 5%, p = 0.01). Positive serology for both VZV and HZ correlated with increased ischemic risk (O.R. 4.01, 95% C.I. 1.38-11.6, p = 0.01 and O.R. 3.14, 95% C.I. 1.12-7.68, p = 0.02, respectively), though chronic heart disease demonstrated stronger predictive value in multivariate analysis(O.R. 8.68, 95% C.I. 2.49-29.50, p = 0.001).

CONCLUSIONS

VZV potentially exacerbates vascular risk in PLWH, particularly in the presence of other predisposing factors. Further research is needed to confirm our data.

Congenital and Perinatal Varicella Infections

Varicella-zoster virus (VZV) is a human pathogen of the α-herpesvirus family. Some fetuses infected in utero around 8-20 weeks of pregnancy show signs of congenital varicella syndrome (CVS). Infants born to mothers who develop varicella within 5 days before and 2 days after delivery can experience severe disease with increased mortality. The best diagnostic modality is polymerase chain reaction (PCR), which can be done using vesicular swabs or scrapings, scabs from crusted lesions, tissue from biopsy samples, and cerebrospinal fluid. The prevention and management of varicella infections include vaccination, anti-VZV immunoglobulin, and specific antiviral drugs. In this article, we have reviewed the characteristics of VZV, clinical manifestations, management of perinatal infections, and short- and long-term prognosis.

A case of reactivation of varicella-zoster virus after BNT162b2 vaccine second dose?

We report a case of itchy papulovesicular rash consistent with varicella-zoster virus reactivation after Pfizer-BioNTech vaccine second dose administration. While there have been cases of varicella-zoster virus reactivation due to COVID-19 or COVID-19 vaccine inoculation in older individuals with pre-existing conditions, this case report describes the first case of varicella-zoster virus reactivation on a healthy, young male in the absence of pre-existing conditions. The mechanisms underlying varicella-zoster virus reactivation in patients with COVID-19 are unknown and should be further characterized.

Pharmacokinetics and Safety of Amenamevir in Healthy Subjects: Analysis of Four Randomized Phase 1 Studies

Introduction

Amenamevir (ASP2151) is a nonnucleoside antiherpesvirus compound available for the treatment of varicella–zoster virus infections. In this article we summarize the findings of four phase 1 studies in healthy participants.

Methods

Four randomized phase 1 studies investigated the safety and pharmacokinetics of single and multiple doses of amenamevir, including the assessment of age group effect (nonelderly vs elderly), food effect, and the relative bioavailability of two formulations. Amenamevir was administered orally at various doses as a single dose (5–2400 mg) or daily (300 or 600 mg/day) for 7 days.

Results

Following single and multiple oral doses, amenamevir demonstrated a less than dose proportional increase in the pharmacokinetic parameters area under the plasma drug concentration versus time curve from time zero to infinity (AUC_inf) and C_max. After single and multiple oral 300-mg doses of amenamevir, no apparent differences in pharmacokinetics were observed between nonelderly and elderly participants. In contrast, with the amenamevir 600-mg dose both the area under the plasma drug concentration versus time curve from time zero to 24 h and C_max were slightly increased and renal clearance was decreased in elderly participants. The pharmacokinetics of amenamevir was affected by food, with AUC_inf increased by about 90%. In the bioavailability study, AUC_inf and C_max were slightly lower following tablet versus capsule administration (decreased by 14 and 12%, respectively), with relative bioavailability of 86%. The different amenamevir doses and formulations were safe and well tolerated; no deaths or serious adverse events were reported.

Conclusion

Amenamevir had less than dose proportional pharmacokinetic characteristics. Age may have an influence on amenamevir pharmacokinetics; however, the effect was considered minimal. The pharmacokinetics of amenamevir were affected by food, with AUC_inf almost doubling when amenamevir was administered with food. The concentration versus time profile of the tablet was slightly lower than that of the capsule; the relative bioavailability of the tablet versus the capsule was 86%. Amenamevir was safe and well tolerated in the dose range investigated.

Funding

Astellas Pharma.

Trial registration

ClinicalTrials.gov identifiers NCT02852876 (15L-CL-002) and NCT02796118 (15L-CL-003).

Electronic supplementary material

The online version of this article (10.1007/s12325-017-0642-4) contains supplementary material, which is available to authorized users.

Pharmacokinetic Evaluation of the Interactions of Amenamevir (ASP2151) with Ketoconazole, Rifampicin, Midazolam, and Warfarin in Healthy Adults

Introduction

Amenamevir is a nonnucleoside antiherpes virus compound available for treating herpes zoster infections. Four studies aimed to determine any potential interactions between amenamevir and ketoconazole, rifampicin, midazolam, or warfarin in healthy male participants.

Methods

Two studies were open-label studies that evaluated the effects of multiple doses of ketoconazole (400 mg) and rifampicin (600 mg) on the pharmacokinetics of a single oral dose of amenamevir. The other two studies were randomized, double-blind, parallel-group studies that evaluated the effects of multiple doses of amenamevir on the pharmacokinetics of a single dose of midazolam (7.5 mg) and warfarin (25 mg). A drug interaction was considered to occur if the 90% confidence interval (CI) of the least squares geometric mean ratio (GMR) of amenamevir to the comparator was outside the prespecified interval of 0.80–1.25.

Results

Interactions were observed between amenamevir and ketoconazole, rifampicin, and midazolam, but not between amenamevir and warfarin. After a single 400-mg dose of amenamevir, the GMRs of amenamevir plus ketoconazole or rifampicin versus amenamevir alone for C_max and the area under the plasma concentration–time curve from time zero to infinity (AUC_inf) were 1.30 (90% CI 1.17–1.45) and 2.58 (90% CI 2.32–2.87), respectively, for ketoconazole and 0.42 (90% CI 0.37–0.49) and 0.17 (90% CI 0.15–0.19), respectively, for rifampicin. Following multiple doses of amenamevir (400 mg), the GMRs of midazolam plus amenamevir versus midazolam alone for AUC_inf and C_max were 0.53 (90% CI 0.47–0.61) and 0.63 (90% CI 0.50–0.80), respectively. After a single dose of warfarin, the (S)-warfarin and (R)-warfarin mean C_max increased and mean AUC_inf decreased in the presence of amenamevir; however, the 90% CIs of the GMRs for these parameters remained within the predefined limits.

Conclusion

These findings confirm that amenamevir (as a cytochrome P450 3A4 substrate) can interact with ketoconazole or rifampicin, and (as a cytochrome P450 3A4 inducer) can interact with midazolam; however, no interaction between amenamevir and (S)-warfarin was observed, indicating that amenamevir is not an inducer of cytochrome P450 2C9.

Funding

Astellas Pharma.

Trial registration

EudraCT2007-002227-33 (study 15L-CL-008), EudraCT2007-002228-14 (study 15L-CL-009), EudraCT2007-002761-13 (study 15L-CL-010), and EudraCT2007-002779-14 (study 15L-CL-018).

Shingles vaccination: background and advice for community nurses

Shingles (or zoster) is a reactivation of an existing varicella-zoster virus (VZV) infection. During the initial infection, VZV causes a systemic disease known as varicella or chickenpox, and this initial infection normally occurs early in childhood in the absence of routine vaccination. Although varicella is normally a mild disease, shingles is associated with significant morbidity and some mortality, particularly in older people. The most significant severe consequence is post-herpetic neuralgia. There is an effective vaccine available for this, known as Zostavax, which is a live-attenuated VZV vaccine. Guidelines in the UK recommend that this is offered to everyone when they become 70 years of age, plus those aged 79 years as part of a catch-up campaign, with those between these ages not being eligible. It is important for all health-care professionals, including district and community nurses, to proactively promote this vaccine, so that those eligible can make an informed decision about whether to receive it.