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Primary vaccination with mRNA-1273 (100-µg) was safe and efficacious at preventing coronavirus disease 2019 (COVID-19) in the previously reported, blinded Part A of the phase 3 Coronavirus Efficacy (COVE; NCT04470427) trial in adults (≥18 years) across 99 U.S. sites. The open-label (Parts B and C) primary objectives were evaluation of long-term safety and effectiveness of primary vaccination plus a 50-µg booster dose; immunogenicity was a secondary objective. Of 29,035 open-label participants, 19,609 received boosters (mRNA-1273 [n = 9647]; placebo-mRNA-1273 [n = 9952]; placebo [n = 10] groups). Booster safety was consistent with that reported for primary vaccination. Incidences of COVID-19 and severe COVID-19 were higher during the Omicron BA.1 than Delta variant waves and boosting versus non-boosting was associated with a significant, 47.0% (95% CI : 39.0-53.9%) reduction of Omicron BA.1 incidence (24.6 [23.4 − 25.8] vs 46.4 [40.6 − 52.7]/1000 person-months). In an exploratory Cox regression model adjusted for time-varying covariates, a longer median interval between primary vaccination and boosting (mRNA-1273 [13 months] vs placebo-mRNA-1273 [8 months]) was associated with significantly lower, COVID-19 risk (24.0% [16.0% − 32.0%]) during Omicron BA.1 predominance. Boosting elicited greater immune responses against SARS-CoV-2 than primary vaccination, irrespective of prior SARS-CoV-2 infection. Primary vaccination and boosting with mRNA-1273 demonstrated acceptable safety, effectiveness and immunogenicity against COVID-19, including emergent variants. Building on evidence from the phase 3 COVE trial, the authors report the long-term safety and effectiveness of primary vaccination and boosting with mRNA-1273 against COVID-19, including during emergent variant waves. [ABSTRACT FROM AUTHOR]

Background: Broadly neutralizing antibodies (bnAbs) are a promising approach for HIV-1 prevention. In the Antibody Mediated Prevention (AMP) trials, a CD4-binding site targeting bnAb, VRC01, administered intravenously (IV), demonstrated 75% prevention efficacy against highly neutralization-sensitive viruses but was ineffective against less sensitive viruses. VRC07-523LS is a next-generation bnAb targeting the CD4-binding site and was engineered for increased neutralization breadth and half-life. We conducted a multicenter, randomized, partially blinded Phase I clinical trial to evaluate the safety and serum concentrations of VRC07-523LS, administered in multiple doses and routes to healthy adults without HIV. Methods and findings: Participants were recruited between 2 February 2018 and 9 October 2018. A total of 124 participants were randomized to receive 5 VRC07-523LS administrations via IV (T1: 2.5 mg/kg, T2: 5 mg/kg, T3: 20 mg/kg), subcutaneous (SC) (T4: 2.5 mg/kg, T5: 5 mg/kg), or intramuscular (IM) (T6: 2.5 mg/kg or P6: placebo) routes at 4-month intervals. Participants and site staff were blinded to VRC07-523LS versus placebo for the IM group, while all other doses and routes were open-label. Safety data were collected for 144 weeks following the first administration. VRC07-523LS serum concentrations were measured by ELISA through Day 112 in all participants and by binding antibody multiplex assay (BAMA) thereafter in 60 participants (10 per treatment group) through Day 784. Compartmental population pharmacokinetic (PK) analyses were conducted to evaluate the VRC07-523LS serum PK. Neutralization activity was measured in a TZM-bl assay and antidrug antibodies (ADAs) were assayed using a tiered bridging assay testing strategy. Injections and infusions were well tolerated, with mild pain or tenderness reported commonly in the SC and IM groups, and mild to moderate erythema or induration reported commonly in the SC groups. Infusion reactions reported in 3 of 20 participants in the 20 mg/kg IV group. Peak geometric mean (GM) concentrations (95% confidence intervals [95% CIs]) following the first administration were 29.0 μg/mL (25.2, 33.4), 58.5 μg/mL (49.4, 69.3), and 257.2 μg/mL (127.5, 518.9) in T1-T3 with IV dosing; 10.8 μg/mL (8.8, 13.3) and 22.8 μg/mL (20.1, 25.9) in T4-T5 with SC dosing; and 16.4 μg/mL (14.7, 18.2) in T6 with IM dosing. Trough GM (95% CIs) concentrations immediately prior to the second administration were 3.4 μg/mL (2.5, 4.6), 6.5 μg/mL (5.6, 7.5), and 27.2 μg/mL (23.9, 31.0) with IV dosing; 0.97 μg/mL (0.65, 1.4) and 3.1 μg/mL (2.2, 4.3) with SC dosing, and 2.6 μg/mL (2.05, 3.31) with IM dosing. Peak VRC07-523LS serum concentrations increased linearly with the administered dose. At a given dose, peak and trough concentrations, as well as serum neutralization titers, were highest in the IV groups, reflecting the lower bioavailability following SC and IM administration. A single participant was found to have low titer ADA at a lone time point. VRC07-523LS has an estimated mean half-life of 42 days across all doses and routes (95% CI: 40.5, 43.5), over twice as long as VRC01 (15 days). Conclusions: VRC07-523LS was safe and well tolerated across a range of doses and routes and is a promising long-acting bnAb for inclusion in HIV-1 prevention regimens. Trial registration: ClinicalTrials.gov/NCT03387150 (posted on 21 December 2017). In a Phase 1 randomised clinical trial, Stephen Walsh and colleagues assess the safety and pharmacokinetics of VRC07-523LS which has been engineered for improved breadth, potency, and a longer half-life. Author summary: Why was this study done?: Broadly neutralizing antibodies (bnAbs), which can block HIV-1 infection in laboratory settings, have considerable promise for HIV-1 prevention in people. In the Antibody Mediated Prevention (AMP) trials, a CD4-binding site (CD4bs) targeting bnAb, VRC01, was found to have 75% prevention efficacy against highly neutralization-sensitive viruses. Most circulating isolates of HIV-1 are less sensitive, and VRC01 was ineffective against those viruses. Our clinical trial was done to assess the safety and drug levels of another CD4bs bnAb called VRC07-523LS, which has been engineered for improved breadth, potency, and a longer half-life. What did the researchers do and find?: We administered VRC07-523LS to healthy volunteers without HIV using multiple routes (intravenous [IV], subcutaneous [SC], and intramuscular [IM]) and at doses ranging from 2.5 mg/kg to 20 mg/kg. VRC07-523LS was safe and well tolerated over more than 30 months of follow-up. At any given dose, peak and trough concentrations, as well as serum neutralization titers, were highest in the IV groups, reflecting the lower bioavailability following SC and IM administration. VRC07-523LS has a half-life of about 42 days, which is over twice as long as VRC01 (15 days). What do these findings mean?: VRC07-523LS was safe and well tolerated across a range of doses and routes and is a promising long-acting bnAb for inclusion in HIV-1 prevention regimens. The main limitations of our study are the small sizes of the individual groups and missing blood draws at the later time points due to COVID-19 restrictions, both of which lead to uncertainty in our estimates of drug levels and pharmacokinetic parameters. Presented in part at: HIV R4P 2021 Virtual (Abstract OA03.01), Cape Town, South Africa, January 2021; and IAS 2022 (Abstract PESUA14), Montréal, Canada, July 2022. [ABSTRACT FROM AUTHOR]

We compared the serologic responses of 1 dose versus 2 doses of a variant vaccine (Moderna mRNA-1273 Beta/Omicron BA.1 bivalent vaccine) in adults. A 2-dose boosting regimen with a variant vaccine did not increase the magnitude or the durability of the serological responses compared to a single variant vaccine boost. [ABSTRACT FROM AUTHOR]

While the coronavirus disease 2019 (COVID-19) pandemic continues to present global challenges, sufficient time has passed to reflect on lessons learned and use those insights to inform policy and approaches to prepare for the next pandemic. In May 2022, the Duke Clinical Research Institute convened a think tank with thought leaders from academia, clinical practice, the pharmaceutical industry, patient advocacy, the National Institutes of Health, the US Food and Drug Administration, and the Centers for Disease Control and Prevention to share, firsthand, expert knowledge of the insights gained from the COVID-19 pandemic and how this acquired knowledge can help inform the next pandemic response. The think tank focused on pandemic preparedness, therapeutics, vaccines, and challenges related to clinical trial design and scale-up during the early phase of a pandemic. Based on the multi-faceted discussions, we outline 10 key steps to an improved and equitable pandemic response. [ABSTRACT FROM AUTHOR]

Vaccine clinical trials have been essential to developing effective severe acute respiratory syndrome coronavirus 2 vaccines. The challenges of supply chain disruptions, infection control, study designs, and participant factors that affect trial procedures are reviewed, with specific solutions to streamline the clinical trial process. [ABSTRACT FROM AUTHOR]

Significant progress has been made in the development, investigation, and clinical application of immunosuppressive agents to treat a variety of autoimmune disorders. The expansion of clinical applications of these new agents requires the performance of large multicenter clinical trials. These large clinical trials are particularly important as one considers these agents for the treatment of type 1 diabetes, which although autoimmune in its pathogenesis, is not classically treated as an autoimmune disorder. Although these agents hold promise for amelioration or cure of this disease, they have the potential to facilitate infectious complications. There are limited data regarding the prospective assessment of infectious risks with these agents in trials of this nature. Pediatric subjects may be at greater risk due to the higher likelihood of primary infection. A subgroup of experts associated with TrialNet (a National Institutes of Health [NIH]-funded Type 1 diabetes mellitus research network) with expertise in infectious diseases, immunology, and diagnostics developed an approach for screening and monitoring of immunosuppression-associated infections for prospective use in clinical trials. The goals of these recommendations are to provide a structured approach to monitor for infections, to identify specific laboratory testing and surveillance methods, and to consider therapies for treatment of these potential complications. Prospective evaluations of these infectious risks allow for greater scientific rigor in the evaluation of risk, which must be balanced with the potential benefits of these therapies. Our experience supports an important role for investigators with expertise in infections in immunocompromised individuals in protocol development of immunosuppressive trials in type 1diabetes and potentially other autoimmune diseases. [ABSTRACT FROM AUTHOR]

Background. Modified vaccinia Ankara (MVA-BN, IMVAMUNE) is emerging as a primary immunogen and as a delivery system to treat or prevent a wide range of diseases. Defining the safety and immunogenicity of MVA-BN in key populations is therefore important.Methods. We performed a dose-escalation study of MVA-BN administered subcutaneously in 2 doses, one on day 0 and another on day 28. Twenty-four hematopoietic stem cell transplant recipients were enrolled sequentially into the study, and vaccine or placebo was administered under a randomized, double-blind allocation. Ten subjects received vaccine containing 107 median tissue culture infective doses (TCID50) of MVA-BN, 10 subjects received vaccine containing 108 TCID50 of MVA-BN, and 4 subjects received placebo.Results. MVA-BN was generally well tolerated at both doses. No vaccine-related serious adverse events were identified. Transient local reactogenicity was more frequently seen at the higher dose. Neutralizing antibodies (NAb) to Vaccinia virus (VACV) were elicited by both doses of MVA-BN and were greater for the higher dose. Median peak anti-VACV NAb titers were 1:49 in the lower-dose group and 1:118 in the higher-dose group. T-cell immune responses to VACV were detected by an interferon γ enzyme-linked immunosorbent spot assay and were higher in the higher-dose group.Conclusions. MVA-BN is safe, well tolerated, and immunogenic in HSCT recipients. These data support the use of 108 TCID50 of MVA-BN in this population.Clinical Trials Registration. NCT00565929. [ABSTRACT FROM PUBLISHER]

Background: The safety and immunogenicity of a vaccine regimen consisting of a 6-plasmid HIV-1 DNA prime (envA, envB, envC, gagB, polB, nefB) boosted by a recombinant adenovirus serotype-5 (rAd5) HIV-1 with matching inserts was evaluated in HIV-seronegative participants from South Africa, United States, Latin America and the Caribbean Methods: 480 participants were evenly randomized to receive either: DNA (4 mg IM by Biojector) at 0, 1 and 2 months, followed by rAd5 (1010 PU IM by needle/syringe) at 6 months; or placebo. Participants were monitored for reactogenicity and adverse events throughout the 12-month study. Peak and duration of HIV-specific humoral and cellular immune responses were evaluated after the prime and boost Results: The vaccine was well tolerated and safe. T-cell responses, detected by interferon-&ggr;(IFN-&ggr;) ELISpot to global potential T-cell epitopes (PTEs) were observed in 70.8% (136/192) of vaccine recipients overall, most frequently to Gag (54.7%) and to Env (54.2%). In U.S. vaccine recipients T-cell responses were less frequent in Ad5 sero-positive versus seronegative vaccine recipients (62.5% versus 85.7% respectively, p = 0.035). The frequency of HIV-specific CD4+ and CD8+ T-cell responses detected by intracellular cytokine staining were similar (41.8% and 47.2% respectively) and most secreted $2 cytokines. The vaccine induced a high frequency (83.7%-94.6%) of binding antibody responses to consensus Group M, and Clades A, B and C gp140 Env oligomers. Antibody responses to Gag were elicited in 46% of vaccine recipients Conclusion: The vaccine regimen was well-tolerated and induced polyfunctional CD4+ and CD8+ T-cells and multi-clade anti-Env binding antibodies [ABSTRACT FROM AUTHOR]

Background. We conducted a clinical trial of the safety and immunogenicity of modified vaccinia Ankara (MVA) to examine the effects of dose and route of administration. Methods. Seventy-two healthy, vaccinia virus-naive subjects received 1 of 6 regimens of MVA (ACAM3000) or placebo consisting of 2 administrations given 1 month apart. Results. MVA was generally well tolerated at all dose levels and by all routes. More pronounced local reactogenicity was seen with the intradermal and subcutaneous routes than with intramuscular administration. Binding antibodies to whole virus and neutralizing antibodies to the intracellular mature virion and extracellular enveloped virion forms of vaccinia virus were elicited by all routes of MVA administration and were greater for the higher dose by each route. Similar levels of neutralizing antibodies were seen at a 10-fold-lower dose given intradermally ( median 1 × 107 tissue culture infective doses [TCID50]), compared with responses after 1 × 108 TCID50 given intramuscularly or subcutaneously. T cell immune responses to vaccinia virus were detected by an interferon g enzyme-linked immunospot assay but had no clear relationship to dose or route. Conclusions. These data suggest that intradermal immunization with MVA provides a dose-sparing effect by eliciting antibody responses similar in magnitude and kinetics to those elicited by the intramuscular or subcutaneous routes but at a 10-fold-lower dose. [ABSTRACT FROM AUTHOR]

Invasive fungal diseases (IFDs) have become major causes of morbidity and mortality among highly immunocompromised patients. Authoritative consensus criteria to diagnose IFD have been useful in establishing eligibility criteria for antifungal trials. There is an important need for generation of consensus definitions of outcomes of IFD that will form a standard for evaluating treatment success and failure in clinical trials. Therefore, an expert international panel consisting of the Mycoses Study Group and the European Organization for Research and Treatment of Cancer was convened to propose guidelines for assessing treatment responses in clinical trials of IFDs and for defining study outcomes. Major fungal diseases that are discussed include invasive disease due to Candida species, Aspergillus species and other molds, Cryptococcus neoformans, Histoplasma capsulatum, and Coccidioides immitis. We also discuss potential pitfalls in assessing outcome, such as conflicting clinical, radiological, and/or mycological data and gaps in knowledge. [ABSTRACT FROM AUTHOR]

Background. In clinical trials, canarypox ALVAC-human immunodeficiency virus (HIV) vaccines have been shown to elicit human HIV-specific cytotoxic T lymphocyte (CTL) responses in some but not all healthy uninfected adults. Methods. A clinical trial was conducted to examine whether the vaccine vCP1452 would elicit a greater HIVspecific CTL response when given at a dose of 108.0 TCID50 (60 participants) than when given at the regular dose, 107.26 TCID50 (40 participants); as a control, a placebo vaccine preparation also was administered (10 participants). Results. Two weeks after the last vaccination in a series, HIV-specific CTL responses were not significantly different when measured by either chromium-release assay (8% and 16% in the high- and regular-dose recipients, respectively) or interferon-γ ELISpot assay (8% and 15% in the high- and regular-dose recipients, respectively); moreover, recipients of the higher dose had greater local and systemic reactions (P < .001 ). Conclusions. High reactogenicity associated with an increased dose of vCP1452 negates the need for further evaluation of this strategy to boost the frequency of HIV-specific CTL response in seronegative human subjects. Development of highly immunogenic canarypox vectors requires further work to optimize vector and insert design, as well as novel ways to increase dosage and to reduce reactogenicity. [ABSTRACT FROM AUTHOR]

• Stochastic interventional vaccine efficacy (SVE) analysis for clinical audience. • SVE analysis estimates how vaccine efficacy (VE) would change under hypothetical immune marker shifts. • First application of SVE to immune correlates based on phase 3 VE trial dataset. • SVE analysis of the COVE messenger RNA-1273 trial supports post dose 2 D614G titer as a CoP. • Predicting variant-specific VE proved difficult due to various reasons. Stochastic interventional vaccine efficacy (SVE) analysis is a new approach to correlate of protection (CoP) analysis of a phase III trial that estimates how vaccine efficacy (VE) would change under hypothetical shifts of an immune marker. We applied nonparametric SVE methodology to the COVE trial of messenger RNA-1273 vs placebo to evaluate post-dose 2 pseudovirus neutralizing antibody (nAb) titer against the D614G strain as a CoP against COVID-19. Secondly, we evaluated the ability of these results to predict VE against variants based on shifts of geometric mean titers to variants vs D614G. Prediction accuracy was evaluated by 13 validation studies, including 12 test-negative designs. SVE analysis of COVE supported post-dose 2 D614G titer as a CoP: estimated VE ranged from 66.9% (95% confidence interval: 36.2, 82.8%) to 99.3% (99.1, 99.4%) at 10-fold decreased or increased titer shifts, respectively. The SVE estimates only weakly predicted variant-specific VE estimates (concordance correlation coefficient 0.062 for post 2-dose VE). SVE analysis of COVE supports nAb titer as a CoP for messenger RNA vaccines. Predicting variant-specific VE proved difficult due to many limitations. Greater anti-Omicron titers may be needed for high-level protection against Omicron vs anti-D614G titers needed for high-level protection against pre-Omicron COVID-19. [ABSTRACT FROM AUTHOR]

The author comments on the Strategies for Management of Antiretroviral Therapy (SMART) trial that was carried out to determine whether withholding therapy for long periods would result in human immunodeficiency viruses (HIV)-associated complications. According to the author, the results of the SMART study underscore the benefit of using adequately powered randomized trials to evaluate new treatment strategies in clinical medicine.

Objective--To evaluate clinical data for cold-stunned Kemp's ridley turtles (Lepidochelys kempii) with Enterococcus spp infections during rehabilitation. Design--Retrospective case series. Animals--50 stranded cold-stunned Kemp's ridley turtles hospitalized between 2006 and 2012. Procedures--Medical records for turtles from which Enterococcus spp were isolated were reviewed retrospectively, and clinical data, including morphometric data, body tempera-ture at admission, physical examination findings, antimicrobial medication history history of medications administered IV, environmental data, day of diagnosis, clinical signs at di-agnosis, microbiological testing results, sources of positive culture results, hematologic and plasma biochemical data, cytologic and histopathologic results, radiographic findings antimicrobial treatments, time to first negative culture result, treatment duration, results of subsequent cultures, and case outcome, were collated and analyzed. Results Enterococcus spp were isolated from bacteriologic cultures of blood, bone, joint, and respiratory tract samples and a skin lesion, with supporting evidence of infection provided by histopathologic, cytologic, and radiographic data. Positive culture results were associated with clinical problems such as lethargy, anorexia, and lameness. Most (34/43 [79%]) turtles for which an antemortem diagnosis was made survived with treatment and were released into the wild. Conclusions and Clinical Relevance--Cold-stunned Kemp's ridley turtles may be af-fected by serious Enterococcus spp infections during rehabilitation. Recognition and treat-ment of these infections are important for successful rehabilitation. [ABSTRACT FROM AUTHOR]

A recent clinical trial of a T-cell-based AIDS vaccine delivered with recombinant adenovirus type 5 (rAd5) vectors showed no efficacy in lowering viral load and was associated with increased risk of human immunodeficiency virus type 1 (HIV-1) infection. Preexisting immunity to Ad5 in humans could therefore affect both immunogenicity and vaccine efficacy. We hypothesized that vaccine-induced immunity is differentially affected, depending on whether subjects were exposed to Ad5 by natural infection or by vaccination. Serum samples from vaccine trial subjects receiving a DNA/rAd5 AIDS vaccine with or without prior immunity to Ad5 were examined for the specificity of their Ad5 neutralizing antibodies and their effect on HIV-1 immune responses. Here, we report that rAd5 neutralizing antibodies were directed to different components of the virion, depending on whether they were elicited by natural infection or vaccination in HIV vaccine trial subjects. Neutralizing antibodies elicited by natural infection were directed largely to the Ad5 fiber, while exposure to rAd5 through vaccination elicited antibodies primarily to capsid proteins other than fiber. Notably, preexisting immunity to Ad5 fiber from natural infection significantly reduced the CD4 and CD8 cell responses to HIV Gag after DNA/rAd5 vaccination. The specificity of Ad5 neutralizing antibodies therefore differs depending on the route of exposure, and natural Ad5 infection compromises Ad5 vaccine-induced immunity to weak immunogens, such as HIV-1 Gag. These results have implications for future AIDS vaccine trials and the design of next-generation gene-based vaccine vectors. [ABSTRACT FROM AUTHOR]

Background: Patients with persistent fever and neutropenia often receive empirical therapy with conventional or liposomal amphotericin B for the prevention and early treatment of invasive fungal infections. Caspofungin, a member of the new echinocandin class of compounds, may be an effective alternative that is better tolerated than amphotericin B. Methods: In this randomized, double-blind, multinational trial, we assessed the efficacy and safety of caspofungin as compared with liposomal amphotericin B as empirical antifungal therapy. At study entry, patients were stratified according to risk and according to whether they had previously received antifungal prophylaxis. A successful outcome was defined as the fulfillment of all components of a five-part composite end point. Results: Efficacy was evaluated in 1095 patients (556 receiving caspofungin and 539 receiving liposomal amphotericin B). After adjustment for strata, the overall success rates were 33.9 percent for caspofungin and 33.7 percent for liposomal amphotericin B (95.2 percent confidence interval for the difference, –5.6 to 6.0 percent), fulfilling statistical criteria for the noninferiority of caspofungin. Among patients with baseline fungal infections, a higher proportion of those treated with caspofungin had a successful outcome (51.9 percent vs. 25.9 percent, P=0.04). The proportion of patients who survived at least seven days after therapy was greater in the caspofungin group (92.6 percent vs. 89.2 percent, P=0.05). Premature study discontinuation occurred less often in the caspofungin group than in the amphotericin B group (10.3 percent vs. 14.5 percent, P=0.03). The rates of breakthrough fungal infections and resolution of fever during neutropenia were similar in the two groups. Fewer patients who received caspofungin sustained a nephrotoxic effect (2.6 percent vs. 11.5 percent, P<0.001), an infusion-related event (35.1 percent vs. 51.6 percent, P<0.001), or a drug-related adverse event or discontinued therapy because of drug-related adverse events. Conclusions: Caspofungin is as effective as and generally better tolerated than liposomal amphotericin B when given as empirical antifungal therapy in patients with persistent fever and neutropenia. N Engl J Med 2004;351:1391-402. [ABSTRACT FROM AUTHOR]