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The recent approval of Palforzia for treatment of peanut allergy by the US Food and Drug Administration (USFDA) predicts that additional products for oral immunotherapy (OIT) are on the horizon. In this article, the authors review the legal framework by which the USFDA regulates products for OIT of food allergy and the clinical data that demonstrated that the safety and effectiveness profile of Palforzia supported approval and conclude with a discussion of oral food challenge (OFC) as a clinical endpoint to demonstrate safety and effectiveness of OIT products.

We previously introduced a three-stage design and associated end-of-stage analyses for allergen immunotherapy (AIT) trials. End-of-stage differences alone may not provide a fuller picture of Stages 2 and 3 effects because they may depend upon stage-specific durations. Therefore, we introduce an additional trend analysis to evaluate the difference in progression curves of two groups over the entire stage. Results from such analysis are used to inform persistence of end-of-stage benefit and thus provide evidence for stagewise effects beyond the study periods. We jointly apply end-of-stage and trend analyses to support the enhanced three-stage design to determine treatment response over time and sustained response to AIT. A simulation study was performed to illustrate the statistical properties (bias and power) of trend analyses under varying statistical missing mechanisms and effect sizes. The extent of bias depended on the missing mechanism and magnitude. Powers were largely driven by effect and sample sizes as well as pre-specified success margins, particularly of relative trend. As an illustration, assuming relative treatment differences of 25–30%, stagewise dropout rate of 15%, and parallel outcome progressions, a sample size of 200 per group may achieve 97% power to demonstrate a treatment effect and 53% power to demonstrate a sustained effect post-treatment. Trend analysis supplements the end-of-stage analysis to enhance the statistical claims of stagewise effects. Inferential statistics support our proposed trend analysis for evaluating benefits of AIT over time and inform clinical understanding and decisions. [ABSTRACT FROM AUTHOR]

Background: Clinical trials of allergen immunotherapy (AIT) may require up to 5 years to complete. These lengthy trials may be complicated by high and potentially differential dropouts, especially among participants who perceive that they are receiving placebo. We propose a three‐stage design in which the placebo group in Stage 1 crosses over to receive active treatment in Stage 2. In Stage 3, AIT is discontinued to determine whether benefit is maintained post‐treatment. We apply inferential statistics to support the three‐stage design for clinical trials to determine clinical efficacy, treatment response over time, and sustained response to AIT. Methods: The proposed framework constitutes a series of hypothesis tests for comparing treatment responses at the end of each stage. A simulation study was performed to illustrate the statistical properties under varying statistical missing mechanisms and effect sizes. Results: The statistical properties in terms of bias and statistical power were consistent with what are expected from conventional analyses. Specifically, the extent of bias depended on the missing mechanism and magnitude. The statistical powers were largely driven by effect and sample sizes as well as prespecified success margins. As an illustration, assuming relative treatment differences of 25% and stagewise dropout rate of 15%, a sample size of 200 per group may achieve 93% power to demonstrate a treatment effect and 60% power to demonstrate a maintained response post‐treatment. Conclusions: Inferential statistics support our proposed study design for evaluating benefits of AIT over time and inform clinical understanding and decisions. [ABSTRACT FROM AUTHOR]

The seventh "Future of the Allergists and Specific Immunotherapy (FASIT)" workshop held in 2019 provided a platform for global experts from academia, allergy clinics, regulatory authorities and industry to review current developments in the field of allergen immunotherapy (AIT). Key domains of the meeting included the following: (a) Biomarkers for AIT and allergic asthma; (b) visions for the future of AIT; (c) progress and data for AIT in asthma and the updates of GINA and EAACI Asthma Guidelines (separated for house dust mite SCIT, SLIT tablets and SLIT drops; patient populations) including a review of clinically relevant endpoints in AIT studies in asthma; (d) regulatory prerequisites such as the "Therapy Allergen Ordinance" in Germany; (e) optimization of trial design in AIT clinical research; (f) challenges planning and conducting phase III (field) studies and the future role of Allergen Exposure Chambers (AEC) in AIT product development from the regulatory point of view. We report a summary of panel discussions of all six domains and highlight unmet needs and possible solutions for the future. [ABSTRACT FROM AUTHOR]

Background: Nonstandardized allergen extracts have been used for a century. Until 1972, these products were regulated by the National Institutes of Health, and products were not required to have an individualized showing of effectiveness. Jurisdiction was then transferred to the US Food and Drug Administration (FDA), which established external review panels to make recommendations regarding safety and effectiveness. Two external panels deliberated, the first from 1974-1979 and the second from 1982-1983. Objective: We sought to review external panels’ recommendations and assess the safety and effectiveness of nonstandardized allergen extracts, FDA-reviewed available literature, and databases since 1972. Methods: Currently licensed nonstandardized allergen extracts were reviewed according to extract type. Available data were collected from medical and nonscientific search engines. Nomenclature was ascertained by consulting www.itis.gov or www.atcc.org. The FDA’s Adverse Event Reporting System was probed for events associated with extract use. Provisional threshold levels of safety and effectiveness were established, and extracts were sorted according to whether they met the thresholds. Results: In the Adverse Event Reporting System, there were 178 adverse event reports, including 13 deaths, associated with allergen extract use over 23 years. No single group of extracts predominated. Among 1269 allergen extracts reviewed, there were 480 for which use in the diagnosis and treatment of allergic disease were addressed in the literature, 207 for which only diagnostic use was addressed, 565 for which minimal or no supportive literature was identified, and 17 for which potential safety concerns were found. Conclusions: When used according to professional guidelines, almost all nonstandardized allergen extracts for diagnosis and therapy appear to be safe. Provisional thresholds of effectiveness were met by 54% of extracts reviewed. [Copyright &y& Elsevier]

Abstract: Natural killer (NK) cells play an important role in both innate and adaptive antiviral immune responses. The adaptive response typically requires that virus-specific antibodies decorate infected cells which then direct NK cell lysis through a CD16 mediated process termed antibody-dependent cellular cytotoxicity (ADCC). In this report, we employ a highly polymerized chimeric IgG1/IgA immunoglobulin (Ig) fusion protein that, by virtue of its capacity to extensively crosslink CD16, activates NK cells while directing the lysis of infected target cells. We employ HIV as a model system, and demonstrate that freshly isolated NK cells preloaded with an HIV gp120-specific chimeric IgG1/IgA fusion protein efficiently lyse HIV-infected target cells at picomolar concentrations. NK cells pre-armed in this manner retain the capacity to kill targets over an extended period of time. This strategy may have application to other disease states including various viral infections and cancers. [Copyright &y& Elsevier]