Intradermal delivery of a quadrivalent cell-based seasonal influenza vaccine using an adjuvanted skin patch vaccination platform.

All seasonal influenza vaccines for 2021-2022 in the US were quadrivalent and the market continues to be dominated by intramuscular delivery of non-adjuvanted, virion-derived antigens grown in chicken eggs. Up to four new egg-adapted production influenza vaccine strains must be generated each year. The introduction in 2012 of Flucelvax®, which is grown in mammalian suspension cell culture and uses vaccine production strains without adaptive mutations for efficient growth in eggs, represented a major advance in vaccine production technology. Here we demonstrate that Flucelvax can be reformulated and combined with a liposomal adjuvant containing QS-21 (Verndari Adjuvant System 1.1, VAS1.1) or QS-21 and 3D-PHAD (VAS1.2) for intradermal administration using a painless skin patch, VaxiPatch™. VAS1.2 is similar to AS01B, the adjuvant system used in Shingrix® and Mosquirix™. We show that Flucelvax, when reformulated and concentrated using tangential flow filtration (TFF), maintains hemagglutination and single radial immunodiffusion (SRID) potency. Loading the reformulated Flucelvax material onto VaxiPatch arrays conferred high levels of resistance to heat stress and room temperature stability. TFF enriched vaccine antigens were combined with VAS1.1 or VAS1.2 and dispensed in 10nL drops into the pockets of 36 (total 360 nL) stainless steel microneedles arranged in a microarray 1.2 cm in diameter. Using VaxiPatch delivery of 2 µg of antigen, we demonstrated intramusuclar-comparable IgG and hemagglutination inhibition (HAI) immune responses in Sprague Dawley® rats. With addition of VAS1.2, antigen-specific IgG titers were increased as much as 68-fold (47-fold for VAS1.1) with improvements in seroconversion for three of four strains (all four were improved by VAS1.1). TFF-reformulated antigens combined with VAS1.1 or VAS1.2 and delivered by VaxiPatch showed only minor skin reactogenicity after 1 h and no skin reactogenicity after 24 h. These data indicate that VaxiPatch and the VAS system have the potential to be transformative for vaccine delivery.

VaxiPatch™, a novel vaccination system comprised of subunit antigens, adjuvants and microneedle skin delivery: An application to influenza B/Colorado/06/2017.

This work introduces VaxiPatch, a novel vaccination system comprised of subunit glycoprotein vaccine antigens, adjuvants and dermal delivery. For this study, rHA of influenza virus B/Colorado/06/2017 was incorporated into synthetic virosomes, and adjuvant liposomes were formed with QS-21 from Saponaria quillaja, with or without the synthetic TLR4 agonist 3D - (6-acyl) PHAD. These components were concentrated and co-formulated into trehalose with dye. Dermal delivery was achieved using an economical 37-point stainless steel microneedle array, designed for automated fill/finish by microfluidic dispensers used for mass production of immunodiagnostics. Vaccine and adjuvant are deposited to form a sugar glass in a pocket on the side of each of the tips, allowing skin penetration to be performed directly by the rigid steel structure. In this study, Sprague Dawley rats (n = 6 per group) were vaccinated by VaxiPatches containing 0.3 µg of rHA, 0.5 µg QS-21 and 0.2 µg 3D - (6-acyl) PHAD and dye, resulting in antigen-specific IgG titers 100-fold higher than 4.5 µg of FluBlok (p = 0.001) delivered intramuscularly. Similarly, hemagglutination inhibition titers in these animals were 14-fold higher than FluBlok controls (p = 0.01). Non-adjuvanted VaxiPatches were also compared with rHA virosomes injected intramuscularly. Accelerated shelf life studies further suggest that formulated virosomal antigens retain activity for at least two months at 60° C. Further, co-formulation of a dye could provide a visible verification of delivery based on the temporary pattern on the skin. A room-temperature-stable vaccination kit such as VaxiPatch has the potential to increase vaccine use and compliance globally.

Dosimetric Implications of Computerised Tomography-Only versus Magnetic Resonance-Fusion Contouring in Stereotactic Body Radiotherapy for Prostate Cancer.

Background: Magnetic resonance (MR)-fusion contouring is the standard of care in prostate stereotactic body radiotherapy (SBRT) for target volume localisation. However, the planning computerised tomography (CT) scan continues to be used for dose calculation and treatment planning and verification. Discrepancies between the planning MR and CT scans may negate the benefits of MR-fusion contouring and it adds a significant resource burden. We aimed to determine whether CT-only contouring resulted in a dosimetric detriment compared with MR-fusion contouring in prostate SBRT planning. Methods: We retrospectively compared target volumes and SBRT plans for 20 patients treated clinically with MR-fusion contouring (standard of care) with those produced by re-contouring using CT data only. Dose was 36.25 Gy in 5 fractions. CT-only contouring was done on two occasions blind to MR data and reviewed by a separate observer. Primary outcome was the difference in rectal volume receiving 36 Gy or above. Results: Absolute target volumes were similar: 63.5 cc (SD ± 27.9) versus 63.2 (SD ± 26.5), Dice coefficient 0.86 (SD ± 0.04). Mean difference in apex superior-inferior position was 1.1 (SD ± 3.5; CI: −0.4–2.6). Small dosimetric differences in favour of CT-only contours were seen, with the mean rectal V36 Gy 0.3 cc (95% CI: 0.1–0.5) lower for CT-only contouring. Conclusions: Prostate SBRT can be successfully planned without MR-fusion contouring. Consideration can be given to omitting MR-fusion from the prostate SBRT workflow, provided reference to diagnostic MR imaging is available. Development of MR-only work flow is a key research priority to gain access to the anatomical fidelity of MR imaging.

Nine-year Follow-up for a Study of Diffusion-weighted Magnetic Resonance Imaging in a Prospective Prostate Cancer Active Surveillance Cohort.

BACKGROUND: In active surveillance (AS) for prostate cancer there are few data on long-term outcomes associated with novel imaging markers. OBJECTIVE: To determine long-term outcomes with respect to the apparent diffusion coefficient (ADC) derived from diffusion-weighted magnetic resonance imaging (DW-MRI) in a prospective AS cohort. Early results have already been published; we now present findings with long-term follow-up. DESIGN, SETTING, AND PARTICIPANTS: A subset of patients (n=86) underwent pre-enrolment DW-MRI in a prospective AS study between 2002 and 2006. Inclusion criteria were untreated prostate cancer, clinical T1/T2a/N0M0, Gleason ≤ 3+4, and prostate-specific antigen (PSA) <15 ng/ml. Protocol follow-up was by biopsy at 18-24 mo and then every 24 mo, with regular PSA measurement. INTERVENTION: Men underwent baseline DW-MRI in addition to standard sequences. ADC was measured from the index lesion on T2-weighted images. To avoid influencing treatment decisions, DW-MRI sequence results were not available to the AS study investigators. OUTCOME MEASUREMENTS AND STATISTICAL ANALYSIS: Baseline ADC was analysed with respect to time to radical treatment (TRT) and time to adverse histology (TAH). Kaplan-Meier analysis and univariate and multivariate regression analyses were performed. RESULTS AND LIMITATIONS: The median follow-up was 9.5 yr (interquartile range 7.9-10.0 yr). On univariate analysis, ADC below the median was associated with shorter TAH (hazard ratio [HR] 2.13, 95% confidence interval [CI] 1.17-3.89; p<0.014) and TRT (HR 2.54, 95% CI 1.49-4.32; p<0.001). Median TRT was 9.3 yr (95% CI 7.0-11.6 yr) for patients with ADC above the median and only 2.4 yr (95% CI 1.5-6.0 yr) for ADC below the median. For TRT, addition of ADC to a multivariate model of baseline variables resulted in a significant improvement in model fit (HR 1.33, 95% CI 1.14-1.54; p<0.001). Receiver operating characteristic analysis for TRT revealed an area under the curve of 0.80 (95% CI 0.70-0.88). The number of variables included in the multivariate model was limited by sample size. CONCLUSIONS: Long-term follow-up for this study provides strong evidence that ADC is a useful marker when selecting patients for AS. Routine DW-MRI is now being evaluated in our ongoing AS study for initial assessment and as an alternative to repeat biopsy. PATIENT SUMMARY: Before entering a study of close monitoring for the initial management of prostate cancer, patients had a type of magnetic resonance imaging scan that looks at the movement of water within cancers. These scans may help in predicting whether patients should receive close monitoring or whether immediate treatment should be given.

An evaluation of a college exercise leader program: using exercise science students as advocates for behavior modification.

BACKGROUND: The purpose of this study was to evaluate a college's exercise leadership program, which was developed to help students, faculty and staff implement behavior changes necessary to begin and maintain a comprehensive exercise program. METHODS: From 2006-2011, a total 66 subjects were recruited and each was assigned to a student exercise leader. Based on comprehensive baseline assessments, each student designed an individualized exercise program for his/her subject. At program completion, the subjects were reassessed. RESULTS: Paired t tests were used to find significant statistical changes (P < .05) among the fitness components. Significant changes as a function of the 6-week exercise program were observed in body weight, body fat percentage, waist circumference, 1-mile walk time, sit-ups, push-ups, and trunk flexion. CONCLUSIONS: Getting started is the most difficult step, but beginning an exercise program has immediate benefits. Institutions of higher education are addressing issues of wellness as a means for increasing graduation, retention, and productivity rates among their campus constituents. These efforts are part of a collaborative effort initiated by the American College Health Association known as Healthy Campus 2020. The findings from this study have a direct impact on programmatic efforts.

Role of synaptic inhibition in turtle respiratory rhythm generation.

In vitro brainstem and brainstem-spinal cord preparations were used to determine the role of synaptic inhibition in respiratory rhythm generation in adult turtles. Bath application of bicuculline (a GABA(A) receptor antagonist) to brainstems increased hypoglossal burst frequency and amplitude, with peak discharge shifted towards the burst onset. Strychnine (a glycine receptor antagonist) increased amplitude and frequency, and decreased burst duration, but only at relatively high concentrations (10-100 microM). Rhythmic activity persisted during combined bicuculline and strychnine application (50 microM each) with increased amplitude and frequency, decreased burst duration, and a rapid onset-decrementing burst pattern. The bicuculline-strychnine rhythm frequency decreased during mu-opioid receptor activation or decreased bath P(C)(O(2)). Synaptic inhibition blockade in the brainstem of brainstem-spinal cord preparations increased burst amplitude in spinal expiratory (pectoralis) nerves and nearly abolished spinal inspiratory activity (serratus nerves), suggesting that medullary expiratory motoneurons were mainly active. Under conditions of synaptic inhibition blockade in vitro, the turtle respiratory network was able to produce a rhythm that was sensitive to characteristic respiratory stimuli, perhaps via an expiratory (rather than inspiratory) pacemaker-driven mechanism. Thus, these data indicate that the adult turtle respiratory rhythm generator has the potential to operate in a pacemaker-driven manner.