Development of a novel air-liquid interface airway tissue equivalent model for in vitro respiratory modeling studies.

The human airways are complex structures with important interactions between cells, extracellular matrix (ECM) proteins and the biomechanical microenvironment. A robust, well-differentiated in vitro culture system that accurately models these interactions would provide a useful tool for studying normal and pathological airway biology. Here, we report the development and characterization of a physiologically relevant air-liquid interface (ALI) 3D airway 'organ tissue equivalent' (OTE) model with three novel features: native pulmonary fibroblasts, solubilized lung ECM, and hydrogel substrate with tunable stiffness and porosity. We demonstrate the versatility of the OTE model by evaluating the impact of these features on human bronchial epithelial (HBE) cell phenotype. Variations of this model were analyzed during 28 days of ALI culture by evaluating epithelial confluence, trans-epithelial electrical resistance, and epithelial phenotype via multispectral immuno-histochemistry and next-generation sequencing. Cultures that included both solubilized lung ECM and native pulmonary fibroblasts within the hydrogel substrate formed well-differentiated ALI cultures that maintained a barrier function and expressed mature epithelial markers relating to goblet, club, and ciliated cells. Modulation of hydrogel stiffness did not negatively impact HBE differentiation and could be a valuable variable to alter epithelial phenotype. This study highlights the feasibility and versatility of a 3D airway OTE model to model the multiple components of the human airway 3D microenvironment.

Organoid Technologies for SARS-CoV-2 Research.

Purpose of Review: Organoids are an emerging technology utilizing three-dimensional (3D), multi-cellular in vitro models to represent the function and physiological responses of tissues and organs. By using physiologically relevant models, more accurate tissue responses to viral infection can be observed, and effective treatments and preventive strategies can be identified. Animals and two-dimensional (2D) cell culture models occasionally result in inaccurate disease modeling outcomes. Organoids have been developed to better represent human organ and tissue systems, and accurately model tissue function and disease responses. By using organoids to study SARS-Cov-2 infection, researchers have now evaluated the viral effects on different organs and evaluate efficacy of potential treatments. The purpose of this review is to highlight organoid technologies and their ability to model SARS-Cov-2 infection and tissue responses. Recent Findings: Lung, cardiac, kidney, and small intestine organoids have been examined as potential models of SARS-CoV-2 infection. Lung organoid research has highlighted that SARS-CoV-2 shows preferential infection of club cells and have shown value for the rapid screening and evaluations of multiple anti-viral drugs. Kidney organoid research suggests human recombinant soluble ACE2 as a preventative measure during early-stage infection. Using small intestine organoids, fecal to oral transmission has been evaluated as a transmission route for the virus. Lastly in cardiac organoids drug evaluation studies have found that drugs such as bromodomain, external family inhibitors, BETi, and apabetalone may be effective treatments for SARs-CoV-2 cardiac injury. Summary: Organoids are an effective tool to study the effects of viral infections and for drug screening and evaluation studies. By using organoids, more accurate disease modeling can be performed, and physiological effects of infection and treatment can be better understood.

Long- and short-term outcomes in renal allografts with deceased donors: A large recipient and donor genome-wide association study.

Improvements in immunosuppression have modified short-term survival of deceased-donor allografts, but not their rate of long-term failure. Mismatches between donor and recipient HLA play an important role in the acute and chronic allogeneic immune response against the graft. Perfect matching at clinically relevant HLA loci does not obviate the need for immunosuppression, suggesting that additional genetic variation plays a critical role in both short- and long-term graft outcomes. By combining patient data and samples from supranational cohorts across the United Kingdom and European Union, we performed the first large-scale genome-wide association study analyzing both donor and recipient DNA in 2094 complete renal transplant-pairs with replication in 5866 complete pairs. We studied deceased-donor grafts allocated on the basis of preferential HLA matching, which provided some control for HLA genetic effects. No strong donor or recipient genetic effects contributing to long- or short-term allograft survival were found outside the HLA region. We discuss the implications for future research and clinical application.

Safety, Pharmacokinetics, and Immunogenicity of Obiltoxaximab After Intramuscular Administration to Healthy Humans.

Inhalational anthrax is a highly lethal infection caused by Bacillus anthracis and a serious bioterrorism threat. Protective antigen (PA) is a critical component required for the virulence of Bacillus anthracis. Obiltoxaximab, a high-affinity monoclonal antibody that neutralizes PA, is approved in the United States for intravenous use for the treatment of inhalational anthrax in combination with appropriate antibacterial drugs and for prophylaxis of inhalational anthrax when alternative therapies are not available or appropriate. Here, we explored the safety, pharmacokinetics (PK), and immunogenicity of obiltoxaximab administered by intramuscular injection at doses of 4, 8, 16, 20, and 24 mg/kg in healthy humans. Systemic exposures were approximately dose proportional, maximum serum concentrations were observed after 6-9 days, and terminal half-life ranged from 16 to 23 days. Average absolute intramuscular bioavailability was 64%. Obiltoxaximab was well tolerated, and local tolerability was acceptable up to 24 mg/kg intramuscularly, up to 6 injections per dose, and up to 5 mL per injection. No injection-site abscesses or hypersensitivity reactions occurred; no subjects developed treatment-emergent antitherapeutic antibodies over the study period of 71 days.

3D printed mitral valve models: affordable simulation for robotic mitral valve repair.

OBJECTIVES: 3D printed mitral valve (MV) models that capture the suture response of real tissue may be utilized as surgical training tools. Leveraging clinical imaging modalities, 3D computerized modelling and 3D printing technology to produce affordable models complements currently available virtual simulators and paves the way for patient- and pathology-specific preoperative rehearsal. METHODS: We used polyvinyl alcohol, a dissolvable thermoplastic, to 3D print moulds that were casted with liquid platinum-cure silicone yielding flexible, low-cost MV models capable of simulating valvular tissue. Silicone-moulded MV models were fabricated for 2 morphologies: the normal MV and the P2 flail. The moulded valves were plication and suture tested in a laparoscopic trainer box with a da Vinci Si robotic surgical system. One cardiothoracic surgery fellow and 1 attending surgeon qualitatively evaluated the ability of the valves to recapitulate tissue feel through surveys utilizing the 5-point Likert-type scale to grade impressions of the valves. RESULTS: Valves produced with the moulding and casting method maintained anatomical dimensions within 3% of directly 3D printed acrylonitrile butadiene styrene controls for both morphologies. Likert-type scale mean scores corresponded with a realistic material response to sutures (5.0/5), tensile strength that is similar to real MV tissue (5.0/5) and anatomical appearance resembling real MVs (5.0/5), indicating that evaluators 'agreed' that these aspects of the model were appropriate for training. Evaluators 'somewhat agreed' that the overall model durability was appropriate for training (4.0/5) due to the mounting design. Qualitative differences in repair quality were notable between fellow and attending surgeon. CONCLUSIONS: 3D computer-aided design, 3D printing and fabrication techniques can be applied to fabricate affordable, high-quality educational models for technical training that are capable of differentiating proficiency levels among users.

Pharmacokinetics and Tolerability of Obiltoxaximab: A Report of 5 Healthy Volunteer Studies.

PURPOSE: This report describes the safety, immunogenicity, and pharmacokinetic results of obiltoxaximab treatment in healthy subjects from 5 clinical trials. METHODS: Healthy men and women were enrolled in randomized, double-blind studies of obiltoxaximab versus placebo (studies 1-3), an open-label, parallel-group study of obiltoxaximab alone versus obiltoxaximab and ciprofloxacin (study 4), or a randomized, double-blind, placebo-controlled study involving administration of a second dose of obiltoxaximab 13 or 119 days after an initial dose (study 5). Obiltoxaximab was administered intravenously in all studies. The safety profile was characterized by physical examinations, including focused examinations of the skin and infusion sites; study drug infusion discontinuations; and assessment of adverse events, vital signs, electrocardiographic findings, laboratory parameters, and immunogenicity. Studies 3 to 5 were the primary safety profile studies. Pharmacokinetic parameters were calculated using noncompartmental methods. FINDINGS: Results of 2 multiple dose studies (studies 1 and 2) revealed that obiltoxaximab exposure increased proportionally. Pharmacokinetic results were consistent across studies. After administration of 16 mg/kg of obiltoxaximab, serum concentrations decreased in a biexponential or multiexponential fashion with a terminal half-life of 17 to 23 days. Mean volume of distribution was approximately 6.3 to 7.5 L, suggesting obiltoxaximab distribution outside the vascular compartment and potentially into tissues. Mean systemic clearance was approximately 0.27 L/d, suggesting that hepatic metabolism and/or renal excretion are not critical to obiltoxaximab elimination. Obiltoxaximab was generally well tolerated. Hypersensitivity reactions were the most common adverse reactions in the safety profile clinical trials, occurring in 34 of 320 subjects (10.6%) receiving obiltoxaximab and 4 of 70 subjects (5.7%) receiving placebo. The most common adverse events were headache, pruritus, upper respiratory tract infection, cough, infusion site swelling, bruising and/or pain, nasal congestion, urticaria, and extremity pain. Of the 320 subjects in the primary safety profile studies who received ≥1 dose of 16 mg/kg of obiltoxaximab, 8 (2.5%) tested positive for a exposure-emergent antiobiltoxaximab response; however, quantitative titers were low (1:20-1:320). IMPLICATIONS: On the basis of consistent results of 5 clinical trials in healthy volunteers, the pharmacokinetic properties of obiltoxaximab after a 16-mg/kg IV infusion can be considered adequately characterized, a criteria of the Animal Rule. Obiltoxaximab appears to be generally well tolerated. ClinicalTrials.gov identifiers: NCT00829582, NCT01453907, NCT01929226, NCT01952444, NCT01932242.

Vedolizumab Pharmacokinetics, Pharmacodynamics, Safety, and Tolerability Following Administration of a Single, Ascending, Intravenous Dose to Healthy Volunteers.

BACKGROUND AND OBJECTIVES: Vedolizumab, a humanized monoclonal antibody against the α4ß7 integrin, is indicated for treatment of moderately to severely active ulcerative colitis or Crohn's disease. In this placebo-controlled, double-blind, randomized, single ascending-dose study, the pharmacokinetics, pharmacodynamics, safety, and tolerability of vedolizumab were evaluated in healthy volunteers. METHODS: Forty-nine participants (in five cohorts) were randomly assigned in a 4:1 ratio to receive a single intravenous infusion of either vedolizumab (0.2, 0.5, 2.0, 6.0, or 10.0 mg/kg) or placebo. Blood samples were collected for measurement of vedolizumab serum concentrations and α4ß7 saturation on peripheral blood lymphocytes by vedolizumab. Pharmacokinetic parameters were computed using a non-compartmental approach. Adverse events were monitored. RESULTS: Vedolizumab maximum observed serum concentration (C max) demonstrated dose proportionality over the dose range tested. Greater than dose-proportional increases in area under the serum concentration-time curve from time 0 to infinity (AUC0-inf) and shorter terminal elimination half-life (t 1/2) were observed from 0.2 to 2.0 mg/kg, suggestive of nonlinear pharmacokinetics at lower doses. At doses higher than 2.0 mg/kg, these parameters increased dose proportionally. Saturation of α4ß7 was at or near maximal levels (>90 %) at all doses and time points when vedolizumab was measurable in serum. A total of 21 of 39 (54 %) vedolizumab-treated participants were anti-drug antibody (ADA) positive, and 11 (28 %) were persistently ADA positive. Overall, no adverse event signals, including serious infections or malignancies, were apparent. CONCLUSIONS: Vedolizumab exhibited target-mediated disposition, characterized by a rapid, saturable, nonlinear elimination process at low concentrations and a slower linear elimination process at higher concentrations. Nearly complete α4ß7 saturation was observed at all doses. A single intravenous infusion of vedolizumab was well tolerated by healthy volunteers.

Occurrence of adverse events among patients with inflammatory bowel disease in the HealthCore Integrated Research Database.

OBJECTIVES: Inflammatory bowel disease (IBD) is a chronic condition commonly requiring lifelong care. Both IBD and IBD-related treatments can cause significant morbidity, and it is often difficult to differentiate their relative etiologic contribution to adverse events (AEs). The objectives of this study were to assess the rates of select AEs among patients with IBD as a function of disease severity and of the use of anti-tumor necrosis factor alpha (anti-TNFα) medications. METHODS: We conducted a retrospective cohort study of IBD patients in the HealthCore Integrated Research Database (HIRD(TM)) between January 2004 and January 2011 to determine rates of AEs in patients with mild and moderate to severe IBD. Key study endpoints were select prespecified malignant neoplasms, infections, and other AEs of interest. RESULTS: A total of 33,386 IBD patients (52.7% ulcerative colitis; 47.3% Crohn's disease) met the inclusion criteria, and 60% had been followed for ≥1 year. Patients with moderate to severe IBD had increased rates of infections, lymphatic and digestive tract cancers, gastrointestinal (GI) perforations, and myocardial infarctions versus patients with mild IBD. Patients with IBD who used anti-TNFα therapies during the study had increased incidence of many types of infections, certain GI cancers (including rectal and anal cancer), intestinal perforations, and kidney stones compared with patients who had never used anti-TNFα therapies. CONCLUSIONS: Results from this large US cohort provide descriptive information on AE rates in a population of IBD patients undergoing routine care, estimating background incidence rates of AEs that are not readily available in the published literature. Our study findings may be limited owing to a lack of generalizability and potential for misclassification due to reliance on medical diagnosis and treatment and procedure codes to identify disease, comorbidities, and treatments. Further research and validation of our findings in other populations and databases are needed.

Long-term clinical experience with vedolizumab in patients with inflammatory bowel disease.

BACKGROUND: Vedolizumab, a gut-selective, anti-inflammatory monoclonal antibody, has shown preliminary efficacy in ulcerative colitis (UC) and Crohn's disease (CD). We report long-term experience with vedolizumab for active UC and CD. METHODS: After a placebo-controlled study, 38 patients with UC were randomized to a loading regimen of vedolizumab 2, 6, or 10 mg/kg on days 1, 15, and 43, followed by maintenance dosing every 8 weeks. Thirty-four vedolizumab-naive patients (15 UC; 19 CD) were randomized to vedolizumab 2, 6, or 10 mg/kg on the same schedule. Rollover patients were treated up to 630 days and treatment-naive patients were treated up to 547 days. RESULTS: Seventy-two patients were dosed; 52 (72%) completed the study. In exploratory analyses, 28 of 72 (39%; UC: 21 of 53, CD: 7 of 19) achieved clinical response and 42 of 72 (58.3%; UC: 38 of 53, CD: 4 of 19) achieved clinical remission. Mean partial Mayo scores declined from baseline through day 155 in both treatment-naive patients with UC (5.4 to 1.7, respectively) and rollover patients with UC (2.3 to 1.4, respectively), leveling off thereafter. Mean Crohn's Disease Activity Index scores decreased from 295 (baseline) to 238 at day 43, continued to trend downward through day 155, and remained below baseline through day 491. Mean Inflammatory Bowel Disease Questionnaire scores increased in all treatment groups. No deaths or systemic opportunistic infections were reported. CONCLUSION: Vedolizumab every 8 weeks for up to 78 weeks had an adverse event profile similar to that previously observed. Mean disease activity indices (partial Mayo score and Crohn's Disease Activity Index score) improved with all 3 doses investigated.

Vedolizumab for the treatment of active ulcerative colitis: a randomized controlled phase 2 dose-ranging study.

BACKGROUND: Vedolizumab is a gut-selective biologic that has shown efficacy in ulcerative colitis (UC) and Crohn's disease (CD). We studied the pharmacokinetics, pharmacodynamics, safety, tolerability, and efficacy of a new formulation of vedolizumab produced by an improved manufacturing process. METHODS: UC patients were randomized to receive vedolizumab (2, 6, or 10 mg/kg) or placebo on days 1, 15, 29, and 85. Safety, pharmacokinetics, pharmacodynamics, and immunogenicity evaluations were performed at multiple timepoints through day 253. Partial Mayo Scores and fecal calprotectin levels were used to assess efficacy. RESULTS: In all, 46 patients (9 placebo, 37 vedolizumab) received at least one dose of study medication. The vedolizumab serum concentration declined monoexponentially until concentrations reached 1-10 µg/mL, and then fell nonlinearly. Vedolizumab maximum serum concentration (C(max) ) and area under the curve (AUC) increased approximately proportionally as a function of dose. Vedolizumab maximally saturated α(4) ß(7) receptors on peripheral serum lymphocytes at all measurable serum concentrations. Vedolizumab was well tolerated, with no deaths and no adverse events leading to discontinuation. At every assessment from day 29 through day 253, over 50% of vedolizumab-treated patients were in clinical response, while placebo response rates generally ranged between 22% and 33%. Vedolizumab treatment reduced fecal calprotectin levels compared with placebo. CONCLUSIONS: Vedolizumab demonstrated dose-proportional pharmacokinetics and maximally saturated α(4) ß(7) receptors over the tested dose range. Multiple dosing up to 10 mg/kg was well tolerated. Over the course of follow-up a greater proportion of patients treated with vedolizumab were in clinical response than those who were assigned to placebo.

MLN3897 plus methotrexate in patients with rheumatoid arthritis: safety, efficacy, pharmacokinetics, and pharmacodynamics of an oral CCR1 antagonist in a phase IIa, double-blind, placebo-controlled, randomized, proof-of-concept study.

OBJECTIVE: To assess the efficacy, safety, pharmacokinetics, and pharmacodynamics of the CC chemokine receptor CCR1 antagonist MLN3897 in patients with rheumatoid arthritis (RA) receiving methotrexate (MTX). METHODS: In this phase IIa, proof-of-concept study, patients meeting the American College of Rheumatology (ACR) criteria for RA who had been taking MTX for >or=6 months with evidence of active disease were randomly assigned to receive either 10 mg oral MLN3897 or matching placebo once daily for 12 weeks (days 1-83) while continuing to receive MTX once a week. Clinical assessments, safety monitoring, and sampling for pharmacokinetic and pharmacodynamic analyses were performed throughout the study. The primary efficacy end point was the difference in the percentage of patients meeting the ACR 20% improvement criteria (achieving an ACR20 response) on day 84 in the MLN3897-treated group compared with that in the placebo-treated group. RESULTS: MLN3897 was well tolerated, with no evidence of systemic immunosuppression. In the intent-to-treat population, there was no significant difference in day 84 ACR20 response rates between MLN3897-treated patients and placebo-treated patients (35% versus 33%, respectively; P=0.72). Results were similar for the per-protocol population. Pharmacokinetic analyses demonstrated no interactions between MLN3897 and MTX. MLN3897 was associated with a high degree of CCR1 occupancy (>or=90% on days 28, 56, and 84 in 82% of patients, by macrophage inflammatory protein 1alpha internalization assay). CONCLUSION: MLN3897 at a concentration of 10 mg once daily had no discernible activity in patients with RA who were also receiving MTX. The results suggest that CCR1 antagonism is unlikely to be a viable strategy for the treatment of RA when used in isolation at the receptor occupancy levels reached in this study.