Phase I study in healthy participants to evaluate safety, tolerability, and pharmacokinetics of inhaled nezulcitinib, a potential treatment for COVID-19.

Nezulcitinib (TD-0903), a lung-selective pan-Janus-associated kinase (JAK) inhibitor designed for inhaled delivery, is under development for treatment of acute lung injury associated with coronavirus disease 2019 (COVID-19). This two-part, double-blind, randomized, placebo-controlled, single ascending dose (part A) and multiple ascending dose (part B) phase I study evaluated the safety, tolerability, and pharmacokinetics (PK) of nezulcitinib in healthy participants. Part A included three cohorts randomized 6:2 to receive a single inhaled dose of nezulcitinib (1, 3, or 10 mg) or matching placebo. Part B included three cohorts randomized 8:2 to receive inhaled nezulcitinib (1, 3, or 10 mg) or matching placebo for 7 days. The primary outcome was nezulcitinib safety and tolerability assessed from treatment-emergent adverse events (TEAEs). The secondary outcome was nezulcitinib PK. All participants completed the study. All TEAEs were mild or moderate in severity, and none led to treatment discontinuation. Overall (area under the plasma concentration-time curve) and peak (maximal plasma concentration) plasma exposures of nezulcitinib were low and increased in a dose-proportional manner from 1 to 10 mg in both parts, with no suggestion of clinically meaningful drug accumulation. Maximal plasma exposures were below levels expected to result in systemic target engagement, consistent with a lung-selective profile. No reductions in natural killer cell counts were observed, consistent with the lack of a systemic pharmacological effect and the observed PK. In summary, single and multiple doses of inhaled nezulcitinib at 1, 3, and 10 mg were well-tolerated in healthy participants, with dose-proportional PK supporting once-daily administration.

Lipoprotein associated phospholipase A(2): role in atherosclerosis and utility as a biomarker for cardiovascular risk.

Atherosclerosis and its clinical manifestations are widely prevalent throughout the world. Atherogenesis is highly complex and modulated by numerous genetic and environmental risk factors. A large body of basic scientific and clinical research supports the conclusion that inflammation plays a significant role in atherogenesis along the entire continuum of its progression. Inflammation adversely impacts intravascular lipid handling and metabolism, resulting in the development of macrophage foam cell, fatty streak, and atheromatous plaque formation. Given the enormous human and economic cost of myocardial infarction, ischemic stroke, peripheral arterial disease and amputation, and premature death and disability, considerable effort is being committed to refining our ability to correctly identify patients at heightened risk for atherosclerotic vascular disease and acute cardiovascular events so that they can be treated earlier and more aggressively. Serum markers of inflammation have emerged as an important component of risk factor burden. Lipoprotein-associated phospholipase A2 (Lp-PLA(2)) potentiates intravascular inflammation and atherosclerosis. A variety of epidemiologic studies support the utility of Lp-PLA(2) measurements for estimating and further refining cardiovascular disease risk. Drug therapies to inhibit Lp-PLA(2) are in development and show considerable promise, including darapladib, a specific molecular inhibitor of the enzyme. In addition to substantially inhibiting Lp-PLA(2) activity, darapladib reduces progression of the necrotic core volume of human coronary artery atheromatous plaque. The growing body of evidence points to an important role and utility for Lp-PLA(2) testing in preventive and personalized clinical medicine.

Lipoprotein-associated phospholipase A2: role in atherosclerosis and utility as a cardiovascular biomarker.

Atherosclerosis and its clinical manifestations are widely prevalent throughout the world. Atherogenesis is highly complex and is modulated by numerous genetic and environmental risk factors. A large body of basic scientific and clinical research supports the conclusion that inflammation plays a significant role in atherogenesis along the entire continuum of its progression. Inflammation adversely impacts intravascular lipid handling and metabolism, resulting in the development of macrophage foam cells, fatty streaks and atheromatous plaque formation. Given the enormous human and economic cost of myocardial infarction, ischemic stroke, peripheral arterial disease and amputation, and premature death and disability, considerable effort is being committed to refining our ability to correctly identify patients at heightened risk for atherosclerotic vascular disease and acute cardiovascular events so that they can be treated earlier and more aggressively. Serum markers of inflammation have emerged as an important component of risk factor burden. Serum lipoprotein-associated phospholipase A(2) (Lp-PLA(2)) potentiates intravascular inflammation and atherosclerosis. A variety of epidemiologic studies support the utility of Lp-PLA(2) measurements for estimating and further refining cardiovascular disease risk. Drug therapies to inhibit Lp-PLA(2) are in development and show considerable promise. In addition to substantially inhibiting Lp-PLA(2), darapladib reduces the progression of the necrotic core volume of coronary artery atheromatous plaque.

Polymer-free cerivastatin-eluting stent shows superior neointimal inhibition with preserved vasomotor function compared to polymer-based paclitaxel-eluting stent in rabbit iliac arteries.

AIMS: The present study was designed to evaluate vasomotor function and vascular biological responses following a novel non-polymeric cerivastatin-eluting stent (CES) versus polymer-based paclitaxel-eluting stent (PES) in a rabbit iliac artery model. Optimisation of DES components and non-polymeric stents may contribute to vascular healing and beneficial to vasomotor function. METHODS AND RESULTS: In vitro human aortic and coronary smooth muscle cells (hASMC & hCSMC), as well as endothelial cells (hAEC & hCEC) were cultured. IC50 curves were determined for cerivastatin (CER). In vivo PES (n=6) and CES (n=12) stents were implanted in nine rabbits. Vasomotor function was investigated at 28 days by acetylcholine (ACh) followed by histopathological and histomorphometric analyses. CER was cytotoxic to hASMC and hCSMC (IC50s of 10-6 M and 10-5 M, respectively), although such cytotoxic effects were not observed for hAEC and hCEC at maximal study dose. PES-associated vasodilation response to endothelial-dependent ACh was significantly suppressed at both proximal and distal adjacent arterial segments, as compared to CES. Furthermore, microscopically, neointimal inhibition quantified by the neointimal cross-sectional area (IA) was superior with CES (0.60 + or - 0.27 mm(2)) compared to PES (1.35 + or - 0.16 mm(2); P <0.05). Medial area was smaller for PES (0.3 + or - 0.04 mm(2)) than CES (0.5 + or - 0.03 mm(2), p <0.001). Additionally, significant inflammation and fibrin deposition was clearly evidenced in PES compared to CES (p <0.05). CONCLUSIONS: CER elicits a differential effect on hSMC compared to hEC in vitro. In contrast to PES, a novel bioabsorbable sol-gel coated CES demonstrated effective neointimal inhibition with less vessel wall toxicity accompanied by preservation of vasomotor function in the rabbit iliac model.

Low-dose paclitaxel elution by novel bioerodible sol-gel coating on stents inhibits neointima with low toxicity in porcine coronary arteries.

OBJECTIVES: The present study was designed to evaluate a novel bioerodible sol-gel film coated paclitaxel-eluting stent (sol-gel-PES, 3 microg per stent) in a porcine coronary artery model. BACKGROUND: Although current polymer-based PES decrease restenosis, the permanent polymer and bound drug have raised concerns regarding delayed vessel healing and late stent thrombosis. METHODS: Polymer-based PES (poly-PES, n = 8), sol-gel-PES (n = 15), bare metal (BMS, n = 14), and sol-gel film only (sham, n = 12), stents were implanted in 17 juvenile pigs. Animals were terminated 28 days post-implant for angiographic restudy and complete histopathologic and histomorphometric analyses. RESULTS: Angiographic late loss was equally reduced for both poly-PES and sol-gel-PES (0.51 +/- 0.64 and 0.61 +/- 0.52 mm, respectively) compared to both BMS and sham (0.98 +/- 0.74 and 1.25 +/- 0.72 mm, p < 0.05). Similarly beneficial results were observed for histomorphometric parameters of neointimal thickness and area, yielding reductions of in-stent stenosis by 43% and 48% for poly-PES, as well as 31% and 37% for sol-gel-PES, vs. BMS and sham, respectively (p < 0.05). Re-endothelialization was complete in all groups. Although the inflammatory cell infiltration and intramural thrombus scores were no different between poly- and sol-gel-PES, medial necrosis was increased for poly-PES (p < 0.05 vs. all others). CONCLUSIONS: A novel bioerodible sol-gel film coated with low-dose paclitaxel demonstrates less toxicity to the coronary tunica media, while retaining effective inhibition of neointimal formation at 28 days.

Pleiotrophin induces formation of functional neovasculature in vivo.

Pleiotrophin (PTN) is a heparin-binding growth/differentiation inducing cytokine that shares 50% amino acid sequence identity and striking domain homology with Midkine (MK), the only other member of the Ptn/Mk developmental gene family. The Ptn gene is expressed in sites of early vascular development in embryos and in healing wounds and its constitutive expression in many human tumors is associated with an angiogenic phenotype, suggesting that PTN has an important role in angiogenesis during development and in wound repair and advanced malignancies. To directly test whether PTN is angiogenic in vivo, we injected a plasmid to express PTN into ischemic myocardium in rats. Pleiotrophin stimulated statistically significant increases in both normal appearing new capillaries and arterioles each of which had readily detectable levels of the arteriole marker, smooth muscle cell alpha-actin. Furthermore, the newly formed blood vessels were shown to interconnect with the existent coronary vascular system. The results of these studies demonstrate directly that PTN is an effective angiogenic agent in vivo able to initiate new vessel formation that is both normal in appearance and function. The data suggest that PTN signals the more "complete" new blood vessel formation through its ability to stimulate different functions in different cell types not limited to the endothelial cell.