Combined integrated protocol/basket trial design for a first-in-human trial

Background: Innovative trial designs are sought to streamline drug development in rare diseases. Basket- and integrated protocol designs are two of these new strategies and have been applied in a handful oncologic trials. We have taken the concept outside the realm of oncology and report about a first-in-human integrated protocol design that facilitates the transition from phase Ia in healthy volunteers to phase Ib in patients with rare complement-mediated disorders driven by the classical pathway.Results: We have been conducting a prospective, double-blind, randomized, placebo-controlled first-in-human study with TNT009, which is a humanized monoclonal antibody directed against the C1s subunit of human complement component C1. The trial consisted of three subparts, including normal healthy volunteers (part one and two) and a single cohort of patients in part three. Patients suffered from various complement-mediated diseases sharing the same pathophysiological mechanism, i.e. bullous pemphigoid, antibody-mediated rejection of organ transplants, cold agglutinin disease and warm autoimmune hemolytic anemia. Primary objective of the trial has been to evaluate the safety and tolerability of TNT009 in humans.Conclusions: This trial provides probably the first example that basket trials may not be limited to single genetic aberrations, which is overly restrictive, but our trial design demonstrates that pathway specificity is a viable paradigm for defining baskets. This will hopefully serve as a role model that could benefit other innovative drug development programs targeting rare diseases

Natural killer cells induce HIV-1 latency reversal after treatment with pan-caspase inhibitors

The establishment of a latency reservoir is the major obstacle for a cure of HIV-1. The shock-and-kill strategy aims to reactivate HIV-1 replication in HIV -1 latently infected cells, exposing the HIV-1-infected cells to cytotoxic lymphocytes. However, none of the latency reversal agents (LRAs) tested so far have shown the desired effect in people living with HIV-1. We observed that NK cells stimulated with a pan-caspase inhibitor induced latency reversal in co-cultures with HIV-1 latently infected cells. Synergy in HIV-1 reactivation was observed with LRAs prostratin and JQ1. The supernatants of the pan-caspase inhibitor-treated NK cells activated the HIV-1 LTR promoter, indicating that a secreted factor by NK cells was responsible for the HIV-1 reactivation. Assessing changes in the secreted cytokine profile of pan-caspase inhibitor-treated NK cells revealed increased levels of the HIV-1 suppressor chemokines MIP1α (CCL3), MIP1β (CCL4) and RANTES (CCL5). However, these cytokines individually or together did not induce LTR promoter activation, suggesting that CCL3-5 were not responsible for the observed HIV-1 reactivation. The cytokine profile did indicate that pan-caspase inhibitors induce NK cell activation. Altogether, our approach might be–in combination with other shock-and-kill strategies or LRAs–a strategy for reducing viral latency reservoirs and a step forward towards eradication of functionally active HIV-1 in infected individuals

Very low doses of rituximab in autoimmune hemolytic anemia—an open-label, phase II pilot trial

IntroductionAlthough rituximab is approved for several autoimmune diseases, no formal dose finding studies have been conducted. The amount of CD20+ cells differs significantly between autoimmune diseases and B-cell malignancies. Hence, dose requirements of anti-CD20 therapies may differ accordingly.MethodsWe conducted a phase II pilot trial investigating the effects and safety of very low doses of rituximab, i.e., 5 mg/m2 every 3 weeks, 20 mg every 4 weeks, 50 mg every 3 months (n = 3 each) and 100 mg every 3 months (n = 1) in patients with autoimmune hemolytic anemia (AIHA) to effectively suppress CD20+ cell counts. Doses were increased if circulating CD20+ cell depletion was insufficient (i.e., <95% reduction from baseline) in a dose group. Plasma rituximab concentrations were quantified by enzyme-linked immunosorbent assay, CD20+ cell counts were determined by flow cytometry.ResultsTen patients were included in the final analysis (7 with cold agglutinin disease, 2 with warm AIHA, 1 with mixed-type AIHA). The first infusion depleted ≥95% of CD20+ cells in all but one of the included patients. However, the dosing regimens were found ineffective, because a sustained CD20+ cell depletion was not achieved, and CD20+ cells recovered with a high interindividual variability. CD20+ lymphocytes were below the detection limit if rituximab plasma concentrations exceeded 0.4 μg/mL. One endokarditis occured.ConclusionRituximab doses as low as 5 mg/m2 transiently depleted CD20+ cells in almost all patients, but the tested low-dose regimens failed to permanently suppress CD20+ cells. The empirically identified EC95% of 0.4 μg/mL rituximab may guide future studies using low-doses of rituximab.Clinical trial registrationhttps://clinicaltrials.gov/, identifier [EudraCT 2016-002478-11]

Osmotic laxatives do not alter dabigatran plasma concentration in healthy volunteers – a randomized, controlled, cross-over trial

BackgroundLaxatives are among the most commonly used pharmacological agents worldwide. Available data indicate a significant potential for clinically relevant drug-drug interactions. We hypothesized that osmotic laxatives may reduce the oral bioavailability of the direct oral anticoagulant dabigatran and thereby its anticoagulant effects.MethodsIn the first part of this single-centre, randomized, double-blind, crossover trial, 24 healthy volunteers received 150 mg dabigatran with placebo (10 g glucose) or 20 g lactulose. In the second, open label part, eight of these 24 healthy volunteers were randomly assigned to receive dabigatran with either 27.6 g macrogol, 30 g flaxseeds, or to receive 20 g lactulose 4-h after dabigatran intake. We measured dabigatran plasma concentrations using an ecarin-based chromogenic assay and calculated the pharmacokinetic parameters. Statistical analysis was performed using a linear mixed-effects model on log-transformed AUC values.ResultsThe main pharmacokinetic parameters AUC, Cmax, Tmax, or t1/2 did not differ significantly between most treatment periods. A reduction in AUC was observed with flaxseed compared to placebo. Dabigatran’s pharmacokinetics remained unaffected by concomitant intake of lactulose or macrogol. There was a high inter- and intra-individual variability in the pharmacokinetics of dabigatran.ConclusionIn this study osmotic laxatives such as lactulose, macrogol or flaxseeds did not affect the pharmacokinetics of dabigatran in healthy individuals. These findings support the safe concurrent use of dabigatran with osmotic laxatives

Inflammatory and Coagulation Biomarkers and Mortality in Patients with HIV Infection

Analyzing biomarker data from participants in a previous randomized controlled trial of continuous versus interrupted HIV treatment (the SMART trial), James Neaton and colleagues find that mortality was related to IL-6 and fibrin D-dimers

Plasma Levels of Transforming Growth Factor-β1 Reflect Left Ventricular Remodeling in Aortic Stenosis

Background: TGF-b1 is involved in cardiac remodeling through an auto/paracrine mechanism. The contribution of TGF-b1 from plasmatic source to pressure overload myocardial remodeling has not been analyzed. We investigated, in patients with valvular aortic stenosis (AS), and in mice subjected to transverse aortic arch constriction (TAC), whether plasma TGF-b1 relates with myocardial remodeling, reflected by LV transcriptional adaptations of genes linked to myocardial hypertrophy and fibrosis, and by heart morphology and function. Methodology/Principal Findings: The subjects of the study were: 39 patients operated of AS; 27 healthy volunteers; 12 mice subjected to TAC; and 6 mice sham-operated. Myocardial samples were subjected to quantitative PCR. Plasma TGF-b1 was determined by ELISA. Under pressure overload, TGF-b1 plasma levels were significantly increased both in AS patients and TAC mice. In AS patients, plasma TGF-b1 correlated directly with aortic transvalvular gradients and LV mass surrogate variables, both preoperatively and 1 year after surgery. Plasma TGF-b1 correlated positively with the myocardial expression of genes encoding extracellular matrix (collagens I and III, fibronectin) and sarcomeric (myosin light chain-2, b-myosin heavy chain) remodelling targets of TGF-b1, in TAC mice and in AS patients. Conclusions/Significance: A circulating TGF-b1-mediated mechanism is involved, in both mice and humans, in the excessive deposition of ECM elements and hypertrophic growth of cardiomyocytes under pressure overload. The possible value of plasma TGF-b1 as a marker reflecting preoperative myocardial remodeling status in AS patients deserves further analysis in larger patient cohorts

The von Willebrand factor A-1 domain binding aptamer BT200 elevates plasma levels of von Willebrand factor and factor VIII: a first-in-human trial

Von Willebrand factor (VWF) and factor VIII (FVIII) circulate in a noncovalent complex in blood and promote primary hemostasis and clotting, respectively. A new VWF A1-domain binding aptamer, BT200, demonstrated good subcutaneous bioavailability and a long half-life in non-human primates. This first-in-human, randomized, placebo-controlled, doubleblind trial tested the hypothesis that BT200 is well tolerated and has favorable pharmacokinetic and pharmacodynamic effects in 112 volunteers. Participants received one of the following: a single ascending dose of BT200 (0.18-48 mg) subcutaneously, an intravenous dose, BT200 with concomitant desmopressin or multiple doses. Pharmacokinetics were characterized, and the pharmacodynamic effects were measured by VWF levels, FVIII clotting activity, ristocetin-induced aggregation, platelet function under high shear rates, and thrombin generation. The mean half-lives ranged from 7-12 days and subcutaneous bioavailability increased dose-dependently exceeding 55% for doses of 6-48 mg. By blocking free A1 domains, BT200 dose-dependently decreased ristocetin-induced aggregation, and prolonged collagen-adenosine diphosphate and shear-induced platelet plug formation times. However, BT200 also increased VWF antigen and FVIII levels 4-fold (P<0.001), without increasing VWF propeptide levels, indicating decreased VWF/FVIII clearance. This, in turn, increased thrombin generation and accelerated clotting. Desmopressin-induced VWF/FVIII release had additive effects on a background of BT200. Tolerability and safety were generally good, but exaggerated pharmacology was seen at saturating doses. This trial identified a novel mechanism of action for BT200: BT200 dose-dependently increases VWF/FVIII by prolonging half-life at doses well below those which inhibit VWF-mediated platelet function. This novel property can be exploited therapeutically to enhance hemostasis in congenital bleeding disorders

Alterations in the human lung proteome with lipopolysaccharide

<p>Abstract</p> <p>Background</p> <p>Recombinant human activated protein C (rhAPC) is associated with improved survival in high-risk patients with severe sepsis; however, the effects of both lipopolysaccharide (LPS) and rhAPC on the bronchoalveolar lavage fluid (BALF) proteome are unknown.</p> <p>Methods</p> <p>Using differential in gel electrophoresis (DIGE) we identified changes in the BALF proteome from 10 healthy volunteers given intrapulmonary LPS in one lobe and saline in another lobe. Subjects were randomized to pretreatment with saline or rhAPC.</p> <p>Results</p> <p>An average of 255 protein spots were detected in each proteome. We found 31 spots corresponding to 8 proteins that displayed abundance increased or decreased at least 2-fold after LPS. Proteins that decreased after LPS included surfactant protein A, immunoglobulin J chain, fibrinogen-γ, α₁-antitrypsin, immunoglobulin, and α₂-HS-glycoprotein. Haptoglobin increased after LPS-treatment. Treatment with rhAPC was associated with a larger relative decrease in immunoglobulin J chain, fibrinogen-γ, α₁-antitrypsin, and α₂-HS-glycoprotein.</p> <p>Conclusion</p> <p>Intrapulmonary LPS was associated with specific protein changes suggesting that the lung response to LPS is more than just a loss of integrity in the alveolar epithelial barrier; however, pretreatment with rhAPC resulted in minor changes in relative BALF protein abundance consistent with its lack of affect in ALI and milder forms of sepsis.</p