Browsing by Author "Baidal, David A."

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    The demise of islet allotransplantation in the United States: A call for an urgent regulatory update
    (Wiley, 2021-04) Witkowski, Piotr; Philipson, Louis H.; Kaufman, Dixon B.; Ratner, Lloyd E.; Abouljoud, Marwan S.; Bellin, Melena D.; Buse, John B.; Kandeel, Fouad; Stock, Peter G.; Mulligan, David C.; Markmann, James F.; Kozlowski, Tomasz; Andreoni, Kenneth A.; Alejandro, Rodolfo; Baidal, David A.; Hardy, Mark A.; Wickrema, Amittha; Mirmira, Raghavendra G.; Fung, John; Becker, Yolanda T.; Josephson, Michelle A.; Bachul, Piotr J.; Pyda, Jordan S.; Charlton, Michael; Millis, J. Michael; Gaglia, Jason L.; Stratta, Robert J.; Fridell, Jonathan A.; Niederhaus, Silke V.; Forbes, Rachael C.; Jayant, Kumar; Robertson, R. Paul; Odorico, Jon S.; Levy, Marlon F.; Harland, Robert C.; Abrams, Peter L.; Olaitan, Oyedolamu K.; Kandaswamy, Raja; Wellen, Jason R.; Japour, Anthony J.; Desai, Chirag S.; Naziruddin, Bashoo; Balamurugan, Appakalai N.; Barth, Rolf N.; Ricordi, Camillo; Surgery, School of Medicine
    Islet allotransplantation in the United States (US) is facing an imminent demise. Despite nearly three decades of progress in the field, an archaic regulatory framework has stymied US clinical practice. Current regulations do not reflect the state-of-the-art in clinical or technical practices. In the US, islets are considered biologic drugs and “more than minimally manipulated” human cell and tissue products (HCT/Ps). In contrast, across the world, human islets are appropriately defined as “minimally manipulated tissue” and not regulated as a drug, which has led to islet allotransplantation (allo-ITx) becoming a standard-of-care procedure for selected patients with type 1 diabetes mellitus. This regulatory distinction impedes patient access to islets for transplantation in the US. As a result only 11 patients underwent allo-ITx in the US between 2016 and 2019, and all as investigational procedures in the settings of a clinical trials. Herein, we describe the current regulations pertaining to islet transplantation in the United States. We explore the progress which has been made in the field and demonstrate why the regulatory framework must be updated to both better reflect our current clinical practice and to deal with upcoming challenges. We propose specific updates to current regulations which are required for the renaissance of ethical, safe, effective, and affordable allo-ITx in the United States.
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    IL-6 receptor blockade does not slow β cell loss in new-onset type 1 diabetes
    (American Society for Clinical Investigation, 2021) Greenbaum, Carla J.; Serti, Elisavet; Lambert, Katharina; Weiner, Lia J.; Kanaparthi, Sai; Lord, Sandra; Gitelman, Stephen E.; Wilson, Darrell M.; Gaglia, Jason L.; Griffin, Kurt J.; Russell, William E.; Raskin, Philip; Moran, Antoinette; Willi, Steven M.; Tsalikian, Eva; DiMeglio, Linda A.; Herold, Kevan C.; Moore, Wayne V.; Goland, Robin; Harris, Mark; Craig, Maria E.; Schatz, Desmond A.; Baidal, David A.; Rodriguez, Henry; Utzschneider, Kristina M.; Nel, Hendrik J.; Soppe, Carol L.; Boyle, Karen D.; Cerosaletti, Karen; Keyes-Elstein, Lynette; Long, S. Alice; Thomas, Ranjeny; McNamara, James G.; Buckner, Jane H.; Sanda, Srinath; ITN058AI EXTEND Study Team; Pediatrics, School of Medicine
    Background: IL-6 receptor (IL-6R) signaling drives development of T cell populations important to type 1 diabetes pathogenesis. We evaluated whether blockade of IL-6R with monoclonal antibody tocilizumab would slow loss of residual β cell function in newly diagnosed type 1 diabetes patients. Methods: We conducted a multicenter, randomized, placebo-controlled, double-blind trial with tocilizumab in new-onset type 1 diabetes. Participants were screened within 100 days of diagnosis. Eligible participants were randomized 2:1 to receive 7 monthly doses of tocilizumab or placebo. The primary outcome was the change from screening in the mean AUC of C-peptide collected during the first 2 hours of a mixed meal tolerance test at week 52 in pediatric participants (ages 6–17 years). Results: There was no statistical difference in the primary outcome between tocilizumab and placebo. Immunophenotyping showed reductions in downstream signaling of the IL-6R in T cells but no changes in CD4 memory subsets, Th17 cells, Tregs, or CD4+ T effector cell resistance to Treg suppression. A DC subset decreased during therapy but regressed to baseline once therapy stopped. Tocilizumab was well tolerated. Conclusion: Tocilizumab reduced T cell IL-6R signaling but did not modulate CD4+ T cell phenotypes or slow loss of residual β cell function in newly diagnosed individuals with type 1 diabetes.
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    Oral Glucose Tolerance Test Measures of First-phase Insulin Response and Their Predictive Ability for Type 1 Diabetes
    (Oxford University Press, 2022) Baidal, David A.; Warnock, Megan; Xu, Ping; Geyer, Susan; Marks, Jennifer B.; Moran, Antoinette; Sosenko, Jay; Evans-Molina, Carmella; Pediatrics, School of Medicine
    Context: Decreased first-phase insulin response (FPIR) during intravenous glucose tolerance testing (IVGTT) is an early indicator of β-cell dysfunction and predictor of type 1 diabetes (T1D). Objective: Assess whether oral glucose tolerance test (OGTT) measures could serve as FPIR alternatives in their ability to predict T1D in autoantibody positive (Aab+) subjects. Design: OGTT and IVGTT were performed within 30 days of each other. Eleven OGTT variables were evaluated for (1) correlation with FPIR and (2) T1D prediction. Setting: Type 1 Diabetes TrialNet "Oral Insulin for Prevention of Diabetes in Relatives at Risk for T1D" (TN-07) and Diabetes Prevention Trial-Type 1 Diabetes (DPT-1) studies clinical sites. Patients: TN-07 (n = 292; age 9.4 ± 6.1 years) and DPT-1 (n = 194; age 15.1 ± 10.0 years) Aab + relatives of T1D individuals. Main outcome measures: (1) Correlation coefficients of OGTT measures with FPIR and (2) T1D prediction at 2 years using area under receiver operating characteristic (ROCAUC) curves. Results: Index60 showed the strongest correlation in DPT-1 (r = -0.562) but was weaker in TN-07 (r = -0.378). C-peptide index consistently showed good correlation with FPIR across studies (TN-07, r = 0.583; DPT-1, r = 0.544; P < 0.0001). Index60 and C-peptide index had the highest ROCAUCs for T1D prediction (0.778 vs 0.717 in TN-07 and 0.763 vs 0.721 in DPT-1, respectively; P = NS), followed by FPIR (0.707 in TN-07; 0.628 in DPT-1). Conclusions: C-peptide index was the strongest measure to correlate with FPIR in both studies. Index60 and C-peptide index had the highest predictive accuracy for T1D and were comparable. OGTTs could be considered instead of IVGTTs for subject stratification in T1D prevention trials.