Post hoc analysis of reactogenicity trends between dose 1 and dose 2 of the adjuvanted recombinant zoster vaccine in two parallel randomized trials

In two large clinical trials (ZOE-50 [NCT01165177] and ZOE-70 [NCT01165229]), two doses of the adjuvanted recombinant zoster vaccine (RZV) demonstrated >90% efficacy against herpes zoster in adults ≥50 years of age. Solicited adverse events (AEs) were collected for 7 days post-each dose in a study sub-cohort. The incidence of reported solicited AEs was higher for RZV compared to placebo recipients. Since reactogenicity may contribute to a person's willingness to be vaccinated, knowing about expected reactogenicity might help keep high compliance with the second dose. This post hoc analysis assessed the intensity of solicited AEs post-dose 2 reported to the same event's intensity post-dose 1. Intensity was graded from 0 to 3, grade 3 indicating the highest severity. Of the vaccinees who did not experience a specific AE post-dose 1, 72.6-91.7% did not experience the same event after dose 2. Although the frequency of grade 3 AEs post-dose 2 was the highest in participants reporting the same AEs at grade 3 post-dose 1, 65.8-89.3% of vaccinees with grade 3 specific AEs post-dose 1 reported the same AEs at lower intensity post-dose 2. These data can help inform health-care professionals about the frequency and intensity of AEs post-dose 2 with respect to post-dose 1.

2780. Reactogenicity Profile of Adjuvanted Recombinant Zoster Vaccine after Dose 2 According to the Intensity of the Same Event Experienced after Dose 1

Background

In the pivotal clinical trials, ZOE-50 (NCT01165177) and ZOE-70 (NCT01165229), the adjuvanted recombinant zoster vaccine (RZV) showed high efficacy against herpes zoster and postherpetic neuralgia. The incidence of reported solicited events was higher in RZV compared with placebo recipients.

Methods

In these phase III, observer-blind, placebo-controlled trials conducted in 18 countries, adults ≥50 years of age (YOA, ZOE-50) and ≥70 YOA (ZOE-70), randomized 1:1, received 2 doses of RZV or placebo 2 months apart. Injection-site and general events were solicited for 7 days after each dose via diary cards in a participant subset. For this post-hoc analysis, ZOE-50 and ZOE-70 data from participants having completed the diary cards for both RZV doses were pooled. The intensity of each solicited event after dose 2 was stratified by the intensity of the same event after dose 1.

Results

Solicited injection-site and general events were recorded for both RZV doses by 4,676 and 4,668 vaccinees, respectively (Figure 1). Of 1,235 vaccinees with no injection-site event at dose 1, 881 (71.3%) reported no injection-site event and 20 (1.6%) reported a grade 3 event after dose 2. A total of 433 (9.3%) vaccinees reported a grade 3 injection-site event, either after dose 1 or dose 2. Of 244 vaccinees with grade 3 injection-site events at dose 1, 79 (32.4%) also reported a grade 3 event after dose 2. Of 2,312 vaccinees with no general event at dose 1, 1,617 (69.9%) reported no general event and 67 (2.9%) reported a grade 3 event after dose 2. A total of 499 (10.7%) vaccinees reported a grade 3 general event, either after dose 1 or dose 2. Of 222 vaccinees with grade 3 general events at dose 1, 81 (36.5%) also reported a grade 3 general event after dose 2. In general, vaccinees who did not experience a certain event after dose 1, did not experience this event after dose 2 either. Most vaccinees reporting a specific event at high intensity after dose 1, reported the same event at a lower intensity (or not at all) after dose 2 (Figures 2 and 3).

Conclusion

While not powered to predict event intensity of the second RZV dose, our data provides an overview of event intensity after RZV dose 2 according to the intensity of the same event experienced after dose 1.

Funding: GlaxoSmithKline Biologicals SA.

Disclosures

All authors: No reported disclosures.

2779. Efficacy of the Adjuvanted Recombinant Zoster Vaccine According to Sex, Geographic Region, and Geographic Ancestry/Ethnicity: A Post-hoc Analysis

Background

The risk of herpes zoster (HZ) has been reported to vary by sex and ethnicity. In 2 large-scale clinical trials, ZOE-50 (NCT01165177) and ZOE-70 (NCT01165229), the adjuvanted recombinant zoster vaccine (RZV) demonstrated high vaccine efficacy (VE) against HZ and post-herpetic neuralgia (PHN). We present a post-hoc analysis of RZV efficacy against HZ and PHN in the ZOE-50/70 population stratified by sex, geographic region and geographic ancestry/ethnicity.

Methods

The ZOE-50 and ZOE-70 studies were phase III, observer-blind, placebo-controlled trials conducted across 5 geographic regions. Adults ≥ 50 years of age (YOA; ZOE-50) and ≥ 70 YOA (ZOE-70), randomized 1:1, received 2 doses of RZV or placebo 2 months apart. Here, VE against HZ by sub-population was estimated from the ZOE-50 population (≥ 50 YOA) and the pooled ZOE-50/70 population (pooled ≥ 70 YOA), and VE against PHN by sub-population was evaluated in the pooled ≥ 70 YOA.

Results

VE was evaluated in 7,340 RZV and 7,413 placebo recipients ≥ 50 YOA (mean age: 62.3 [RZV], 62.2 [placebo] YOA) and 8,250 RZV and 8,346 placebo recipients in pooled ≥ 70 YOA (mean age: 75.5 [RZV, placebo] YOA). VE against HZ and PHN was similar for women and men in the ≥ 50 YOA and pooled ≥ 70 YOA (Tables 1 and 2). Point estimates for VE against HZ by geographic region ranged from 95.7% to 97.2% in ≥ 50 YOA and from 87.3% to 95.1% in pooled ≥ 70 YOA (Table 1). Point estimates for VE against PHN by geographic region ranged from 86.8% to 100% in pooled ≥ 70 YOA. VE was similar across geographic ancestry groups in pooled ≥ 70 YOA: VE point estimates against HZ ranged from 89.6% to 100% and VE against PHN ranged from 87.5% to 100% (Tables 1 and 2). VE against HZ was 88.1% and against PHN was 65.9% in Hispanic participants in pooled ≥ 70 YOA (Tables 1 and 2).

Conclusion

Acknowledging the limitations including the post-hoc character of these analyses and the small number of participants and cases available, our data suggest that RZV is efficacious against HZ and PHN irrespective of sex, geographic region, geographic ancestry, and ethnicity.

Funding: GlaxoSmithKline Biologicals SA.

Disclosures

All authors: No reported disclosures.

Assessment of the “Skin Reservoir” of Urea by Confocal Raman Microspectroscopy and Reverse Iontophoresis in vivo

PURPOSE

To demonstrate the "skin reservoir" of urea by confocal Raman microspectroscopy in vivo and to evaluate its impact on the non-invasive monitoring of the analyte by reverse iontophoresis.

METHODS

Urea was extracted iontophoretically over a 2-h period across the skin of adult volunteers and patients with chronic kidney disease. Confocal Raman microspectroscopic profiles of skin were recorded before and after 30 min of current application.

RESULTS

Urea extraction was higher at the beginning of current passage, but then decreased to achieve stable values after 2 h of iontophoresis. After 30 min of iontophoresis, the Raman spectra highlighted a clear depletion of urea at the surface of the skin. Lactate distribution was also modified both at the surface and deeper into the skin.

CONCLUSIONS

A source of urea in the skin, unrelated to the concentration circulating in the blood, was strongly suggested by extracted urea flux observed over time and by the Raman spectroscopy. This "urea reservoir" must be removed before systemic urea levels can be non-invasively monitored by reverse iontophoresis.

Improvement of the decision efficiency of the accuracy profile by means of a desirability function for analytical methods validation

Validation of analytical methods is a widely used and regulated step for each analytical method. However, the classical approaches to demonstrate the ability to quantify of a method do not necessarily fulfill this objective. For this reason an innovative methodology was recently introduced by using the tolerance interval and accuracy profile, which guarantee that a pre-defined proportion of future measurements obtained with the method will be included within the acceptance limits. Accuracy profile is an effective decision tool to assess the validity of analytical methods. The methodology to build such a profile is detailed here. However, as for any visual tool it has a part of subjectivity. It was then necessary to make the decision process objective in order to quantify the degree of adequacy of an accuracy profile and to allow a thorough comparison between such profiles. To achieve this, we developed a global desirability index based on the three most important validation criteria: the trueness, the precision and the range. The global index allows the classification of the different accuracy profiles obtained according to their respective response functions. A diacetyl-monoxime colorimetric assay for the determination of urea in transdermal iontophoretic extracts was used to illustrate these improvements.

Monitoring of Urea and Potassium by Reverse Iontophoresis In Vitro

PURPOSE

Reverse iontophoresis is an alternative to blood sampling for the monitoring of endogenous molecules. Here, the potential of the technique to measure urea and potassium levels non-invasively, and to track their concentrations during hemodialysis, has been examined.

MATERIALS AND METHODS

In vitro experiments were performed to test (a) a series of subdermal urea and potassium concentrations typical of the pathophysiologic range, and (b) a decreasing profile of urea and potassium subdermal concentrations to mimic those which are observed during hemodialysis.

RESULTS

(a) After 60-120 min of iontophoresis, linear relationships (p < 0.05) were established between both urea and potassium fluxes and their respective subdermal concentrations. The determination coefficients were above 0.9 after 1 h of current passage using sodium as an internal standard. (b) Reverse iontophoretic fluxes of urea and K(+) closely paralleled the decay of the respective concentrations in the subdermal compartment, as would occur during a hemodialysis session.

CONCLUSIONS

These in vitro experiments demonstrate that urea and potassium can be quantitatively and proportionately extracted by reverse iontophoresis, even when the subdermal concentrations of the analytes are varying with time. These results suggest the non-invasive monitoring of urea and potassium to diagnose renal failure and during hemodialysis is feasible, and that in vivo measurements are warranted.

Reverse iontophoresis of lithium: electrode formulation using a thermoreversible polymer

This work investigated the use of a thermoreversible gel as a collector vehicle in reverse iontophoresis applications. A 20% (w/w) aqueous gel of Pluronic F127 was a suitable receptor medium to be used at the cathodal chamber. In vitro iontophoresis experiments investigated the simultaneous extraction of lithium (analyte of interest) and sodium (used as an internal standard) into either a control buffer or a gelled receptor. The gelification process at room temperature provided a suitable consistency and contact with the skin surface during the iontophoresis experiments. Subsequent cooling of the gelled solution to 4 degrees C allows an easy recovery of lithium and sodium for later quantification. Both the lithium extraction fluxes and the lithium to sodium ratio of extraction fluxes were linearly related to the subdermal lithium concentration. On the whole, the results show that thermoreversible polymer solutions offer a simple and convenient way to handle samples in reverse iontophoresis studies.