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Human serum albumin (HSA) is currently used as a plasma expander (PE) to increase blood volume during hypovolemic conditions, such as blood loss. However, its effectiveness is suboptimal in septic shock and burn patients due to their enhanced endothelial permeability, resulting in HSA extravasation into the tissue space leading to edema, and deposition of toxic HSA-bound metabolites. Hence, to expand HSA's applicability toward treating patients with compromised endothelial permeability, HSA has been previously polymerized to increase its molecular size thus compartmentalizing the polymerized HSA (PolyHSA) molecules in the vascular space. Previous studies bracketed PolyHSA between 100 kDa and 0.2 μm. In this research, PolyHSA was synthesized at two cross-link densities 43:1 and 60:1 (i.e., molar ratios of glutaraldehyde to HSA) and subsequently fractionated via tangential flow filtration (TFF) into two narrower brackets: bracket A (500 kDa and 0.2 μm) and bracket B (50-500 kDa). PolyHSA within the same size bracket at different cross-link densities exhibited similar solution viscosity, zeta potential, and osmolality but differed in hydrodynamic diameter. At the same cross-link density, the PolyHSA A bracket showed higher viscosity, lowered zeta potential, and a larger hydrodynamic diameter compared with the PolyHSA B bracket while maintaining osmolality. Interestingly, PolyHSA 43:1 B, PolyHSA 60:1 A, and PolyHSA 60:1 B brackets exhibited colloid osmotic pressure similar to HSA, indicating their potential to serve as PEs.

This study aims to investigate the effects of hypoxically stored Red Blood Cells (RBCs) in a rat model of traumatic brain injury followed by severe hemorrhagic shock (HS) and resuscitation. RBCs were made hypoxic using an O2 depletion system (Hemanext Inc. Lexington, MA) and stored for 3 weeks. Experimental animals underwent craniotomy and blunt brain injury followed by severe HS. Rats were resuscitated with either fresh RBCs (FRBCs), 3-week-old hypoxically stored RBCs (HRBCs), or 3-week-old conventionally stored RBCs (CRBCs). Resuscitation was provided via RBCs transfusion equivalent to 70 % of the shed blood and animals were followed for 2 h. The control group was comprised of healthy animals that were not instrumented or injured. Post-resuscitation hemodynamics and lactate levels were improved with FRBCs and HRBCs, and markers of organ injury in the liver (Aspartate aminotransferase [AST]), lung (chemokine ligand 1 [CXCL-1] and Leukocytes count), and heart (cardiac troponin, Interleukin- 6 [IL-6] and Tumor Necrosis Factor Alpha[TNF-α]) were lower with FRBCs and HRBCs resuscitation compared to CRBCs. Following reperfusion, biomarkers for oxidative stress, lipid peroxidation, and RNA/DNA injury were assessed. Superoxide dismutase [SOD] levels in the HRBCs group were similar to the FRBCs group and levels in both groups were significantly higher than CRBCs. Catalase levels were not different than control values in the FRBCs and HRBCs groups but significantly lower with CRBCs. Thiobarbituric acid reactive substances [Tbars] levels were higher for both CRBCs and HRBCs. Hypoxically stored RBCs show few differences from fresh RBCs in resuscitation from TBI + HS and decreased organ injury and oxidative stress compared to conventionally stored RBCs.

High-molecular-weight linear polymers (HMWLPs) have earned the name "drag-reducing polymers" because of their ability to reduce drag in turbulent flows. Recently, these polymers have become popular in bioengineering applications. This study investigated whether the addition of HMWLP in a venoarterial extracorporeal circulation (ECC) model could improve microvascular perfusion and oxygenation. Golden Syrian hamsters were instrumented with a dorsal skinfold window chamber and subjected to ECC using a circuit comprised of a peristaltic pump and a bubble trap. The circuit was primed with lactated Ringer solution (LR) containing either 5 ppm of polyethylene glycol (PEG) with a low molecular weight of 500 kDa (PEG500k) or 5 ppm of PEG with a high molecular weight of 3,500 kDa (PEG3500k). After 90 min of ECC at 15% of the animal's cardiac output, the results showed that the addition of PEG3500k to LR improved microvascular blood flow in arterioles and venules acutely (2 h after ECC), whereas functional capillary density showed improvement up to 24 h after ECC. Similarly, PEG3500k improved venular hemoglobin O2 saturation on the following day after ECC. The serum and various excised organs all displayed reduced inflammation with the addition of PEG3500k, and several of these organs also had a reduction in markers of damage with the HMWLPs compared to LR alone. These promising results suggest that the addition of small amounts of PEG3500k can help mitigate the loss of microcirculatory function and reduce the inflammatory response from ECC procedures.NEW & NOTEWORTHY High-molecular-weight linear polymers have gained traction in bioengineering applications. The addition of PEG3500k to lactated Ringer solution (LR) improved microvascular blood flow in arterioles and venules acutely after extracorporeal circulation (ECC) in a hamster model and improved functional capillary density up to 24 h after ECC. PEG3500k improved venular hemoglobin O2 saturation and oxygen delivery acutely after ECC and reduced inflammation in various organs compared to LR alone.

In drug development a frequently used phrase is data-driven. Just as high-test gas fuels a car, so drug development runs on high-quality data; hence, good data management practices, which involve case report form design, data entry, data capture, data validation, medical coding, database closure, and database locking, are critically important. This review covers the essentials of clinical data management (CDM) for the United States. It is intended to demystify CDM, which means nothing more esoteric than the collection, organization, maintenance, and analysis of data for clinical trials. The review is written with those who are new to drug development in mind and assumes only a passing familiarity with the terms and concepts that are introduced. However, its relevance may also extend to experienced professionals that feel the need to brush up on the basics. For added color and context, the review includes real-world examples with RRx-001, a new molecular entity in phase III and with fast-track status in head and neck cancer, and AdAPT-001, an oncolytic adenovirus armed with a transforming growth factor-beta (TGF-β) trap in a phase I/II clinical trial with which the authors, as employees of the biopharmaceutical company, EpicentRx, are closely involved. An alphabetized glossary of key terms and acronyms used throughout this review is also included for easy reference.

The pathophysiologic mechanism of sickle cell disease (SCD) involves polymerization of deoxygenated haemoglobin S (HbS), leading to red blood cell (RBC) sickling, decreased RBC deformability, microvascular obstruction, haemolysis, anaemia and downstream clinical complications. Pharmacological increase in the concentration of oxygenated HbS in RBCs has been shown to be a novel approach to inhibit HbS polymerization and reduce RBC sickling and haemolysis. We report that GBT021601, a small molecule that increases HbS-oxygen affinity, inhibits HbS polymerization and prevents RBC sickling in blood from patients with SCD. Moreover, in a murine model of SCD (SS mice), GBT021601 reduces RBC sickling, improves RBC deformability, prolongs RBC half-life and restores haemoglobin levels to the normal range, while improving oxygen delivery and increasing tolerance to severe hypoxia. Notably, oral dosing of GBT021601 in animals results in higher levels of Hb occupancy than voxelotor and suggests the feasibility of once-daily dosing in humans. In summary, GBT021601 improves RBC health and normalizes haemoglobin in SS mice, suggesting that it may be useful for the treatment of SCD. These data are being used as a foundation for clinical research and development of GBT021601.

Their widespread presence throughout the vasculature, coupled with their reactivity, and thereby to their potential to release reactive oxidative species, or to utilize their anti-oxidative capacities, has promoted much discussion of the role(s) of red blood cells (RBCs) in the progression of health or, alternatively, a wide range of disease states. Moreover, these role(s) have been linked to the development of adhesiveness and, in fact, thereby to the essential pathway to their eventual clearance, e.g., by macrophages in the spleen. These disparate roles coupled with the mechanisms involved are reviewed and given. Following an analysis, novel perspectives are provided; these perspectives can lead to novel assays for identifying the potential for RBC adhesiveness as suggested herein. We describe this paradigm, that involves RBC adhesiveness, hemolysis, and ghost formation, with examples including, inter alia, the progression of atherosclerosis and the suppression of tumor growth along with other disease states.

Chronic unresolving inflammation is emerging as a key underlying pathological feature of many if not most diseases ranging from autoimmune conditions to cardiometabolic and neurological disorders. Dysregulated immune and inflammasome activation is thought to be the central driver of unresolving inflammation, which in some ways provides a unified theory of disease pathology and progression. Inflammasomes are a group of large cytosolic protein complexes that, in response to infection- or stress-associated stimuli, oligomerize and assemble to generate a platform for driving inflammation. This occurs through proteolytic activation of caspase-1-mediated inflammatory responses, including cleavage and secretion of the proinflammatory cytokines interleukin (IL)-1β and IL-18, and initiation of pyroptosis, an inflammatory form of cell death. Several inflammasomes have been characterized. The most well-studied is the nucleotide-binding domain (NOD)-like receptor protein 3 (NLRP3) inflammasome, so named because the NLRP3 protein in the complex, which is primarily present in immune and inflammatory cells following activation by inflammatory stimuli, belongs to the family of nucleotide-binding and oligomerization domain (Nod) receptor proteins. Several NLRP3 inflammasome inhibitors are in development, all with multi-indication activity. This review discusses the current status, known mechanisms of action, and disease-modifying therapeutic potential of RRx-001, a direct NLRP3 inflammasome inhibitor under investigation in several late-stage anticancer clinical trials, including a phase 3 trial for the treatment of third-line and beyond small cell lung cancer (SCLC), an indication with no treatment, in which RRx-001 is combined with reintroduced chemotherapy from the first line, carboplatin/cisplatin and etoposide (ClinicalTrials.gov Identifier: NCT03699956). Studies from multiple independent groups have now confirmed that RRx-001 is safe and well tolerated in humans. Additionally, emerging evidence in preclinical animal models suggests that RRx-001 could be effective in a wide range of diseases where immune and inflammasome activation drives disease pathology.

Decellularized extracellular matrix in the form of patches and locally injected hydrogels has long been used as therapies in animal models of disease. Here we report the safety and feasibility of an intravascularly infused extracellular matrix as a biomaterial for the repair of tissue in animal models of acute myocardial infarction, traumatic brain injury and pulmonary arterial hypertension. The biomaterial consists of decellularized, enzymatically digested and fractionated ventricular myocardium, localizes to injured tissues by binding to leaky microvasculature, and is largely degraded in about 3 d. In rats and pigs with induced acute myocardial infarction followed by intracoronary infusion of the biomaterial, we observed substantially reduced left ventricular volumes and improved wall-motion scores, as well as differential expression of genes associated with tissue repair and inflammation. Delivering pro-healing extracellular matrix by intravascular infusion post injury may provide translational advantages for the healing of inflamed tissues 'from the inside out'.

RRx-001 is a shape shifting small molecule with Fast Track designation for the prevention/amelioration of chemoradiation-induced severe oral mucositis (SOM) in newly diagnosed Head and Neck cancer. It has been intentionally developed or engineered as a chimeric single molecular entity that targets multiple redox-based mechanisms. Like an antibody drug conjugate (ADC), RRx-001 contains, at one end a targeting moiety, which binds to the NLRP3 inflammasome and inhibits it as well as Kelch-like ECH-associated protein 1 (KEAP1), the negative regulator of Nrf2, and, at the other end, a conformationally constrained, dinitro containing 4 membered ring, which fragments under conditions of hypoxia and reduction to release therapeutically active metabolites i.e., the payload. This payload, which is delivered specifically to hypoperfused and inflamed areas, includes nitric oxide, nitric oxide related species and carbon-centered radicals. As observed with ADCs, RRx-001 contains a backbone amide linker attached to a binding site, which correlates with the Fab region of an antibody, and to the dinitroazetidine payload, which is microenvironmentally activated. However, unlike ADCs, whose large size impacts their pharmacokinetic properties, RRx-001 is a nonpolar small molecule that easily crosses cell membranes and the blood brain barrier (BBB) and distributes systemically. This short review is organized around the de novo design and in vivo pro-oxidant/pro-inflammatory and antioxidant/anti-inflammatory activity of RRx-001, which, in turn, depends on the reduced to oxidized glutathione ratio and the oxygenation status of tissues.

BackgroundBromonitrozidine (RRx-001) is a minimally toxic, NLRP3 inhibitor that has been observed, in experimental systems, to also downregulate CD47, repolarize tumor associated macrophages (TAMs) and normalize aberrant tumor perfusion. This phase 1 pilot study was undertaken to determine the safety and feasibility of RRx-001 and nivolumab in patients with advanced cancer and no standard options.MethodsThis single arm, single site, open-label pilot study (NCT02518958) called PRIMETIME was designed to evaluate the safety profile of RRx-001 and nivolumab in patients with advanced malignancies and no other standard therapeutic options. A 3 + 3 trial design was used to establish safety of the combination at each dose level and guide the decision to escalate dose. RRx-001 is infused once weekly while nivolumab is given at 3mg/kg once every 2 weeks. The RRx-001 starting dose was 2 mg IV weekly with 4 dose level escalations up to 16 mg IV weekly. From January 2015 to November 2015, twelve patients received treatment for only 4 cycles (total 12 weeks) with the combination due to unavailability of nivolumab, which was not supplied to the Sponsor. Treatment-emergent (all cause, TEAEs) and treatment-related (TRAEs) adverse events that occurred within 16 weeks of the first dose of RRx-001 and nivolumab were characterized according to CTCAE v4.03.ResultsTwelve patients received ≥1 dose of RRx-001 and nivolumab. One discontinuation occurred due to pneumonitis and one to voluntary withdrawal after a post-procedural infection. There were no DLTs. The main adverse event related to RRx-001 was infusion reaction (33.3%). The main adverse event related to the combination was pseudoprogression manifested by larger tumors in patients that were symptomatically improved (25%). The most common immune-related treatment-emergent AEs were pneumonitis (8.3%), and hypothyroidism (8.3%). The objective response rate at 12 weeks was 25% and the disease control rate (DCR) consisting of ≥SD was 67% by Response Evaluation Criteria in Solid Tumors (RECIST) version 1.1. 25% of the patients progressed on the combination.ConclusionsThe combination of RRx-001 and nivolumab was safe and well-tolerated with preliminary evidence of anti-cancer activity. Further clinical trials with RRx-001 and nivolumab are warranted.Clinical trial registrationClinicalTrials.gov identifier, NCT02518958.

Infection with COVID-19 has resulted in over 276,000 deaths in the United States and over 1.5 million deaths globally, with upwards of 15% of patients requiring hospitalization. Severe COVID-19 infection is, in essence, a microvascular disease. This contention has been emphasized throughout the course of the pandemic, particularly due to the clinical manifestation of severe infection. In fact, it has been hypothesized and shown in particular instances that microvascular function is a significant prognosticator for morbidity and mortality. Initially thought to be isolated to the pulmonary system and resulting in ARDS, patients with COVID-19 have been observed to have acute cardiac, renal, and thrombolytic complications. Therefore, severe COVID-19 is a vascular disease that has systemic implications. The objective of this review is to provide a mechanistic background for the microvascular nature of severe COVID-19 infection, with a particular emphasis on dysfunction of the endothelial glycocalyx and nitric oxide mediated pathogenesis.

Extracorporeal circulation (ECC) procedures, such as cardiopulmonary bypass (CPB) and extracorporeal membrane oxygenation (ECMO), take over the function of one or more organs, providing clinicians time to treat underlying pathophysiological conditions. ECMO and CPB carry significant mortality rates for patients, despite prior decades of research focused on the resulting failure of critical organs. Since the focus of these procedures is to support blood flow and provide oxygen-rich blood to tissues, a shift in research toward the effects of ECMO and CPB on the microcirculation is warranted. Along with provoking systemic responses, both procedures disrupt the integrity of red blood cells, causing release of hemoglobin (Hb) from excessive foreign surface contact and mechanical stresses. The effects of hemolysis are especially pronounced in the microcirculation, where plasma Hb leads to nitric oxide scavenging, oxidization, formation of reactive oxygen species, and inflammatory responses. A limited number of studies have investigated the implications of ECMO in the microcirculation, but more work is needed to minimize ECMO-induced reduction of microcirculatory perfusion and consequently oxygenation. The following review presents existing information on the implications of ECMO and CPB on microvascular function and proposes future studies to understand and leverage key mechanisms to improve patient outcomes.

For the past thirty years, hemoglobin-based oxygen carriers (HBOCs) have been under development as a red blood cell substitute. Side-effects such as vasoconstriction, oxidative injury, and cardiac toxicity have prevented clinical approval of HBOCs. Recently, high molecular weight (MW) polymerized human hemoglobin (PolyhHb) has shown positive results in rats. Studies have demonstrated that high MW PolyhHb increased O2 delivery, with minimal effects on blood pressure, without vasoconstriction, and devoid of toxicity. In this study, we used guinea pigs to evaluate the efficacy and safety of high MW PolyhHb, since like humans guinea pigs cannot produce endogenous ascorbic acid, which limits the capacity of both species to deal with oxidative stress. Hence, this study evaluated the efficacy and safety of resuscitation from severe hemorrhagic shock with high MW PolyhHb, fresh blood, and blood stored for 2 weeks. Animals were randomly assigned to each experimental group, and hemorrhage was induced by the withdrawal of 40% of the blood volume (BV, estimated as 7.5% of body weight) from the carotid artery catheter. Hypovolemic shock was maintained for 50 min. Resuscitation was implemented by infusing 25% of the animal's BV with the different treatments. Hemodynamics, blood gases, total hemoglobin, and lactate were not different before hemorrhage and during shock between groups. The hematocrit was lower for the PolyhHb group compared to the fresh and stored blood groups after resuscitation. Resuscitation with stored blood had lower blood pressure compared to fresh blood at 2 h. There was no difference in mean arterial pressure between groups at 24 h. Resuscitation with PolyhHb was not different from fresh blood for most parameters. Resuscitation with PolyhHb did not show any remarkable change in liver injury, inflammation, or cardiac damage. Resuscitation with stored blood showed changes in liver function and inflammation, but no kidney injury or systemic inflammation. Resuscitation with stored blood after 24 h displayed sympathetic hyper-activation and signs of cardiac injury. These results suggest that PolyhHb is an effective resuscitation alternative to blood. The decreased toxicities in terms of cardiac injury markers, vital organ function, and inflammation following PolyhHb resuscitation in guinea pigs indicate a favorable safety profile. These results are promising and support future studies with this new generation of PolyhHb as alternative to blood when blood is unavailable.

The multi-kinase inhibitor Regorafenib, approved for the treatment of metastatic colorectal cancer, is poorly tolerated with a Grade 3/4 drug related adverse event rate of 54% resulting in frequent dose reductions and discontinuations. RRx-001 is a minimally toxic NLRP3 inhibitor small molecule with macrophage-repolarizing properties in Phase 3 clinical trials. Studies have demonstrated the inhibitory impact of M2 macrophages on the activity of tyrosine kinases, suggesting that the repolarization of macrophages by RRx-001 may enhance the activity of TKIs. The purpose of these experiments was to determine whether RRx-001 demonstrated in vitro and in vivo synergy with regorafenib in colorectal cancer and whether RRx-001 attenuated the toxicity of regorafenib. Tumor-bearing mice were randomized into four cohorts: RRx-001 alone, regorafenib alone, RRx-001 + regorafenib and control. RRx-001 demonstrated in vitro and in vivo synergy with regorafenib with attenuation of toxicity in colorectal cancer cell lines. These results provide a rationale to treat colorectal cancer with RRx-001 plus another tyrosine kinase inhibitor like regorafenib.