Immune response and reactogenicity of intradermal administration versus subcutaneous administration of varicella-zoster virus vaccine: an exploratory, randomised, partly blinded trial.

BACKGROUND: The licensed live, attenuated varicella-zoster virus vaccine prevents herpes zoster in adults older than 50 years. We aimed to determine whether intradermal administration of zoster vaccine could enhance vaccine immunogenicity compared with conventional needle subcutaneous administration. METHODS: In this randomised, dose-ranging study, adults aged 50 years or older who had a history of varicella or who had resided in a country with endemic varicella-zoster virus infection for 30 years or more were eligible. Participants received the approved full or a 1/3 dose of zoster vaccine given subcutaneously or one of four intradermal doses (full, 1/3, 1/10, or 1/27 dose) using the MicronJet600 device. The two subcutaneous doses and the four intradermal doses were randomised (1·5:1:1:1:1:1) by computer generated sequence with randomisation stratified by age (50-59 years or 60 years or older). The primary immunogenicity endpoint was the change from baseline in IgG antibody to varicella-zoster virus-specific glycoproteins (gpELISA) measured at 6 weeks. All patients were included in the primary and safety analyses. This study is registered with ClinicalTrials.gov, number NCT01385566. FINDINGS: Between Sept 2, 2011, and Jan 13, 2012, 224 participants were enrolled from three clinics in the USA and 223 were randomly assigned: 52 to receive the full dose subcutaneous zoster vaccine, 34 to receive the 1/3 dose subcutaneous zoster vaccine, 34 to receive the full dose intradermal zoster vaccine, 35 to receive the 1/3 dose intradermal zoster vaccine, 34 to receive the 1/10 dose intradermal zoster vaccine, and 34 to receive the 1/27 dose intradermal zoster vaccine. Full dose zoster vaccine given subcutaneously resulted in a gpELISA geometric mean fold-rise (GMFR) of 1·74 (90% CI 1·48-2·04) at 6 weeks post-vaccination compared with intradermal administration which resulted in a significantly higher gpELISA GMFR of 3·25 (2·68-3·94; p<0·0001), which also remained high at 18 months. An apparent dose-response relation was observed with intradermal administration (1/3 dose subcutaneous GMFR 1·64 [90% CI 1·36-1·99], 1/3 dose intradermal 2·58 (2·13-3·13), 1/10 dose intradermal 2·22 [1·83-2·69], and 1/27 dose intradermal 1·64 [1·35-2·00]). Each partial dose of zoster vaccine given intradermaly had a gpELISA GMFR comparable to that of full dose zoster vaccine given subcutaneously. Transient erythema and induration were more common after intradermal administration (31% erythema for full subcutaneous dose and 77% for intradermal dose). INTERPRETATION: Intradermal zoster vaccine showed a greater increase in varicella-zoster virus gpELISA antibody compared with subcutaneous zoster vaccine at comparable doses. Larger and longer studies of intradermal administration of live, attenuated zoster vaccine are needed to provide convincing evidence of improved cell mediated immunity. FUNDING: Merck & Co Inc.

Pre-vaccination inflammation and B-cell signalling predict age-related hyporesponse to hepatitis B vaccination.

Aging is associated with hyporesponse to vaccination, whose mechanisms remain unclear. In this study hepatitis B virus (HBV)-naive older adults received three vaccines, including one against HBV. Here we show, using transcriptional and cytometric profiling of whole blood collected before vaccination, that heightened expression of genes that augment B-cell responses and higher memory B-cell frequencies correlate with stronger responses to HBV vaccine. In contrast, higher levels of inflammatory response transcripts and increased frequencies of pro-inflammatory innate cells correlate with weaker responses to this vaccine. Increased numbers of erythrocytes and the haem-induced response also correlate with poor response to the HBV vaccine. A transcriptomics-based pre-vaccination predictor of response to HBV vaccine is built and validated in distinct sets of older adults. This moderately accurate (area under the curve≈65%) but robust signature is supported by flow cytometry and cytokine profiling. This study is the first that identifies baseline predictors and mechanisms of response to the HBV vaccine.

Dipeptidyl peptidase-4 inhibition in patients with type 2 diabetes treated with saxagliptin, sitagliptin, or vildagliptin.

INTRODUCTION: Saxagliptin, sitagliptin, and vildagliptin are dipeptidyl peptidase-4 (DPP-4) inhibitors widely approved for use in patients with type 2 diabetes. Using a crossover design, the present study compared trough levels of DPP-4 inhibition provided by these agents in a single cohort of patients with type 2 diabetes. METHODS: This was a randomized, placebo-controlled, open-label, five-period crossover study. Eligible patients were 18-65 years of age, either treatment-naïve or off prior antihyperglycemic agent therapy for at least 6 or 12 weeks (depending on the prior therapy), and had glycated hemoglobin (HbA1C) ≥6.5% and ≤10.0%. In separate study periods, patients received 5 mg saxagliptin q.d. (saxa-5), 100 mg sitagliptin q.d. (sita-100), 50 mg vildagliptin q.d. (vilda-50-q.d.), 50 mg vildagliptin b.i.d. (vilda-50-b.i.d.), or placebo for 5 days. The primary endpoint was trough %DPP-4 inhibition, derived by comparing DPP-4 activity 24 h after the Day-5 morning dose with predose activity in the same period and analyzed using a linear mixed-effects model with fixed-effects terms for treatment and period. RESULTS: Mean (range) baseline HbA1C was 7.4% (6.4-9.0%; N = 22). Least-squares (LS) mean trough %DPP-4 inhibition was 73.5%, 91.7%, 28.9%, 90.6%, and 3.5% after saxa-5, sita-100, vilda-50-q.d., vilda-50-b.i.d., and placebo, respectively. In patients treated with sita-100, the LS-mean difference in trough %DPP-4 inhibition was 18.2% greater than with saxa-5 (p < 0.001), 62.9% greater than with vilda-50-q.d. (p < 0.001), 1.1% greater than with vilda-50-b.i.d. (p = 0.128), and 87.8% greater than with placebo (p < 0.001). Mean %DPP-4 inhibition was nearly maximal at 12 h postdose regardless of active treatment. Thus, these between-group comparisons at trough primarily reflected differences in duration of action. Adverse events reported during the study were transient and mild or moderate in intensity. CONCLUSION: Once daily treatment with sitagliptin provided trough DPP-4 inhibition significantly greater than saxagliptin or vildagliptin administered once daily, and similar to that provided by vildagliptin administered twice daily.

Repeatability of edited lactate and other metabolites in astrocytoma at 3T.

PURPOSE: To assess the repeatability of measurement of lactate and other metabolites in tumors using magnetic resonance spectroscopy (MRS). MATERIALS AND METHODS: MRS with spectral editing for lactate was performed on 10 patients with astrocytoma (two Grade III, eight Grade IV) using an 8-channel receive coil at 3T. Lactate, lipid, choline, creatine, and N-acetyl aspartate (NAA) signals were measured in regions of tumor and contralateral white matter. Metabolites were quantified relative to unsuppressed water using LCModel fitting software. RESULTS: The within-patient coefficients of variation were ≈16% (tumor lactate), 6%-8% (tumor choline and contralateral choline, creatine, and NAA), and 22% (tumor lipid). As expected due to their low concentration in normal tissue, lactate and lipid were not reliably detected in white matter but were found at high levels in most tumors. NAA and creatine were lower in tumors than in normal white matter, and choline varied between above- and below-normal values. No consistent short-term variation in metabolite levels was observed, despite differences in the time elapsed since administration of contrast agent. CONCLUSION: MRS appears repeatable enough to provide longitudinal measures of metabolite content in tumors and contralateral tissue in the brain in vivo.