The Quinazoline Otaplimastat (SP-8203) Reduces the Hemorrhagic Transformation and Mortality Aggravated after Delayed rtPA-Induced Thrombolysis in Cerebral Ischemia.

Acute ischemic stroke is the leading cause of morbidity and mortality worldwide. Recombinant tissue plasminogen activator (rtPA) is the only agent clinically approved by FDA for patients with acute ischemic stroke. However, delayed treatment of rtPA (e.g., more than 3 h after stroke onset) exacerbates ischemic brain damage by causing intracerebral hemorrhage and increasing neurotoxicity. In the present study, we investigated whether the neuroprotant otaplimastat reduced delayed rtPA treatment-evoked neurotoxicity in male Sprague Dawley rats subjected to embolic middle cerebral artery occlusion (eMCAO). Otaplimastat reduced cerebral infarct size and edema and improved neurobehavioral deficits. In particular, otaplimastat markedly reduced intracerebral hemorrhagic transformation and mortality triggered by delayed rtPA treatment, consequently extending the therapeutic time window of rtPA. We further found that ischemia-evoked extracellular matrix metalloproteases (MMPs) expression was closely correlated with cerebral hemorrhagic transformation and brain damage. In ischemic conditions, delayed rtPA treatment further increased brain injury via synergistic expression of MMPs in vascular endothelial cells. In oxygen-glucose-deprived endothelial cells, otaplimastat suppressed the activity rather than protein expression of MMPs by restoring the level of tissue inhibitor of metalloproteinase (TIMP) suppressed in ischemia, and consequently reduced vascular permeation. This paper shows that otaplimastat under clinical trials is a new drug which can inhibit stroke on its own and extend the therapeutic time window of rtPA, especially when administered in combination with rtPA.

Safety and Efficacy of Otaplimastat in Patients with Acute Ischemic Stroke Requiring tPA (SAFE-TPA): A Multicenter, Randomized, Double-Blind, Placebo-Controlled Phase 2 Study.

OBJECTIVE: Otaplimastat is a neuroprotectant that inhibits matrix metalloprotease pathway, and reduces edema and intracerebral hemorrhage induced by recombinant tissue plasminogen activator (rtPA) in animal stroke models. We aimed to assess the safety and efficacy of otaplimastat in patients receiving rtPA. METHODS: This was a phase 2, 2-part, multicenter trial in stroke patients (19-80 years old) receiving rtPA. Intravenous otaplimastat was administered <30 minutes after rtPA. Stage 1 was a single-arm, open-label safety study in 11 patients. Otaplimastat 80 mg was administered twice daily for 3 days. Stage 2 was a randomized, double-blind, placebo-controlled study involving 69 patients, assigned (1:1:1) to otaplimastat 40 mg, otaplimastat 80 mg, or a placebo. The primary endpoint was the occurrence of parenchymal hematoma (PH) on day 1. Secondary endpoints included serious adverse events (SAEs), mortality, and modified Rankin scale (mRS) distribution at 90 days (clinicaltrials.gov identifier: NCT02787278). RESULTS: No safety issues were encountered in stage 1. The incidence of PH during stage 2 was comparable: 0 of 22 with the placebo, 0 of 22 with otaplimastat 40 mg, and 1 of 21 with the 80 mg dose. No differences in SAEs (13%, 17%, 14%) or death (8.3%, 4.2%, 4.8%) were observed among the 3 groups. Three adverse events (chills, muscle rigidity, hepatotoxicity) were judged to be related to otaplimastat. INTERPRETATION: Intravenous otaplimastat adjunctive therapy in patients receiving rtPA is feasible and generally safe. The functional efficacy of otaplimastat needs to be investigated with further large trials. ANN NEUROL 2020;87:233-245.

Antithrombotic effect of SP-8008, a benzoic acid derivative, through the selective inhibition of shear stress-induced platelet aggregation.

BACKGROUND AND PURPOSE: Bleeding is one of the most critical adverse effects of antithrombotic drugs, and many efforts have been made to discover novel antiplatelet agents without bleeding complications. Shear stress-induced platelet aggregation (SIPA), where the interaction of von Willebrand factor (vWF) and platelet glycoprotein (GP) Ib constitutes the initial step, is a promising target to overcome bleeding problems, as SIPA occurs only in pathological conditions. Here, we describe SP-8008, a novel modulator of vWF-GP Ib interactions and evaluated its antiplatelet/antithrombotic effects. EXPERIMENTAL APPROACH: Newly synthesized compounds were screened for antiplatelet effects in vitro, using human platelets exposed to high shear stress. Aggregation, intracellular calcium level, granule secretion, and integrin activation were assessed. Molecular modelling using virtual docking and flow cytometry were used to evaluate effects on vWF-GP Ib interactions. Antithrombotic effects in vivo were determined in rats, using arterial thrombosis and shear stress-specific thrombosis. Transection tail bleeding time was used to evaluate adverse effects. KEY RESULTS: SP-8008 was a potent inhibitor of SIPA, with IC50 of 1.44 ± 0.09 µM. SP-8008 effectively and broadly blocked shear stress-induced platelet activation events, without any significant toxicity. Importantly, SP-8008 was highly selective against SIPA, effectively interfering with vWF-GP Ib engagement. Most importantly, SP-8008 exerted significant antithrombotic effects in vivo in both shear stress-specific and arterial thrombosis, without prolonging bleeding time. CONCLUSIONS AND IMPLICATIONS: Our results demonstrated that SP-8008 can be a novel selective antiplatelet agent with improved safety profile.

Inhibitors of bone resorption from Halenia corniculata.

Eleven xanthones (1-11), three flavonoids (12-14) and three secoiridoids (15-17) were isolated from the aerial parts of Halenia corniculata. Among those compounds, 1-hydroxy-2,3,4,5-tetramethoxyxanthone (1), 1-hydroxy-2,3,4,7-tetramethoxyxanthone (2), 1-hydroxy-2,3,4,5,7-pentamethoxyxanthone (3), 1-hydroxy-2,3,5-trimethoxyxanthone (4), 1,8-dihydroxy-3,5-dimethoxyxanthone (7), and luteolin (12), at the concentration of 1 microg/mL, effectively inhibited the osteoclast differentiation in a co-culture system with mouse osteoblastic calvarial cells and bone marrow cells. Notably, compounds 1, 3, and 4 exhibited, in a dose-dependent manner, significant inhibition of osteoclast differentiation even at a low concentration (0.01 microg/mL). All the inhibitory compounds, except for compound 7, significantly reduced the pit formation on the dentine slice compared with the control group. For the survival of the mature osteoclasts, compounds 1-4 and 12 (1 microg/mL), significantly decreased the survival number through induction of cell apoptosis, and compound 4 exhibited a significant inhibitory effect on osteoclast survival even at the low concentration of 0.1 microg/mL.

Inhibitors of osteoclast differentiation from Cephalotaxus koreana.

Three new flavonoid glycosides ( 1- 3), 11-hydroxyhainanolidol ( 4), and a new dibenzylbutyrolactone lignan glycoside ( 5) were isolated from the aerial parts of Cephalotaxus koreana Nakai, along with 19 known flavonoids. The structures of the new compounds were elucidated using spectroscopic evidence, primarily NMR and MS. Twenty-four compounds were isolated, and among these isoscutellarein 5-O-beta-D-glucopyranoside ( 3), apigenin ( 6), kaempferol 3-O-alpha-L-rhamnopyranosyl(1'''-->6'')-beta-D-glucopyranoside ( 7), tamarixetin 3-O-alpha-L-rhamnopyranosyl(1'''-->6'')-beta-D-glucopyranoside ( 8), quercetin 3-O-[6''-O-acetyl]-beta-D-glucopyranoside ( 9), and quercetin 3-O-alpha-L-rhamnopyranoside ( 10) showed significant inhibitory activities against osteoclast differentiation at concentrations of 0.1 and 1.0 microg/mL.

Inhibition of HCV replicon cell growth by 2-arylbenzofuran derivatives isolated from Mori Cortex Radicis.

Medicinal herbs are increasingly used in the search for safe and efficient drug candidates for hepatitis C virus infection. In this study, we have investigated the anti-HCV effect of compounds from Mori Cortex Radicis. During a screening for extracts with anti-HCV affinity from medicinal plants (173 species), the methanol extract of Mori Cortex Radicis was selected. Fractionation of the extract by monitoring antiviral activity with a replicon cell-based assay resulted in the isolation of five compounds, mulberroside C ( 1), moracin P ( 2), moracin O ( 3), moracin M ( 4) and mulberrofuran K ( 5) from the ethyl acetate-soluble fraction. Compounds 1 approximately 4 showed significant inhibitory activities. Compounds 2 and 3 showed potent inhibitory activity (IC (50) 35.6 microM, 80.8 microM, respectively) in the replicon cell assay, which was confirmed by NS3 helicase inhibitory activity (IC (50) 42.9 microM, 27.0 microM, respectively).

In vitro and in vivo activities of DW-224a, a novel fluoroquinolone antibiotic agent.

OBJECTIVES: The objective of the present study was to assess the in vitro and in vivo activities of DW-224a in order to eventually use it as an antibiotic. METHODS: DW-224a was compared with DW286, ciprofloxacin and trovafloxacin. MICs of DW-224a, DW286, ciprofloxacin and trovafloxacin were determined against several groups of clinical isolates. In addition, intraperitoneal infection was induced with various organisms in mice. Test compounds were administered once orally to mice immediately after infection. The 50% protective dose (PD50) was calculated from the survival rates on day 7 after infection. RESULTS: Against Gram-positive bacteria, the in vitro activity of DW-224a was stronger than those of ciprofloxacin and trovafloxacin, but slightly weaker than that of DW286. Against Gram-negative bacteria, the activity of DW-224a was similar to those of trovafloxacin and DW286, but weaker than that of ciprofloxacin. In experimental systemic infections in mice with various organisms, like DW286, DW-224a demonstrated potent activity against Gram-positive bacteria and somewhat less activity against Gram-negative bacteria. CONCLUSIONS: DW-224a has a broad spectrum of antimicrobial activity, which is especially potent against Gram-positive bacteria.

Antipneumococcal activity of DW-224a, a new quinolone, compared to those of eight other agents.

DW-224a is a new broad-spectrum quinolone with excellent antipneumococcal activity. Agar dilution MIC was used to test the activity of DW-224a compared to those of penicillin, ciprofloxacin, levofloxacin, gatifloxacin, moxifloxacin, gemifloxacin, amoxicillin-clavulanate, cefuroxime, and azithromycin against 353 quinolone-susceptible pneumococci. The MICs of 29 quinolone-resistant pneumococci with defined quinolone resistance mechanisms against seven quinolones and an efflux mechanism were also tested. DW-224a was the most potent quinolone against quinolone-susceptible pneumococci (MIC(50), 0.016 microg/ml; MIC(90), 0.03 microg/ml), followed by gemifloxacin, moxifloxacin, gatifloxacin, levofloxacin, and ciprofloxacin. beta-Lactam MICs rose with those of penicillin G, and azithromycin resistance was seen mainly in strains with raised penicillin G MICs. Against the 29 quinolone-resistant strains, DW-224a had the lowest MICs (0.06 to 1 microg/ml) compared to those of gemifloxacin, clinafloxacin, moxifloxacin, gatifloxacin, levofloxacin, and ciprofloxacin. DW-224a at 2x MIC was bactericidal after 24 h against eight of nine strains tested. Other quinolones gave similar kill kinetics relative to higher MICs. Serial passages of nine strains in the presence of sub-MIC concentrations of DW-224a, moxifloxacin, levofloxacin, ciprofloxacin, gatifloxacin, gemifloxacin, amoxicillin-clavulanate, cefuroxime, and azithromycin were performed. DW-224a yielded resistant clones similar to moxifloxacin and gemifloxacin but also yielded lower MICs. Azithromycin selected resistant clones in three of the five parents tested. Amoxicillin-clavulanate and cefuroxime did not yield resistant clones after 50 days.

Effective local control of prostate cancer by intratumoral injection of (166)Ho-chitosan complex (DW-166HC) in rats.

PURPOSE: The aim of this study was to evaluate the therapeutic effect and morphological alterations resulting from (166)Ho-chitosan complex (DW-166HC) in an animal model of prostate cancer. METHODS: First, in a subcutaneous tumor model, 80 rats were randomly divided into four groups (n=20 in each group), and intratumoral injections of 0.05 ml (normal saline in group 1,( 165)Ho-chitosan complex solution in group 2, DW-166HC solution (10 mCi) in group 3, and DW-166HC solution (20 mCi) in group 4) were performed when the tumor measured approximately 1 cm along its long axis in each group. Further, in an orthotopic tumor model, 40 rats were similarly randomly divided into four groups (n=10 in each group), and intraprostatic injections of 0.05 ml [PBS in group 1,( 165)Ho-chitosan complex solution in group 2, DW-166HC solution (0.5 mCi) in group 3 and DW-166HC solution (1 mCi) in group 4] were performed at 1 week after implantation of the AIT cell line in the ventral prostate. RESULTS: In the subcutaneous tumor model, mean tumor weights of groups 3 and 4 were significantly lower than those of groups 1 and 2 at 2 and 4 weeks post injection (p<0.05). At 2 and 4 weeks after injection in the orthotopic tumor model, the mean weights of the prostate, including tumor, in groups 3 and 4 were also significantly lower than those in groups 1 and 2 (p<0.05). No adverse injury was seen in adjacent organs at histopathologic examination. CONCLUSION: Intratumoral injection of the beta-emitting radionuclide (166)Ho as a form of complex solution with chitosan appears to be a promising alternative therapeutic modality for the local control of prostate cancer.

Biodistribution and excretion of radioactivity after the administration of 166Ho-chitosan complex (DW-166HC) into the prostate of rat.

PURPOSE: The objective of this study was to determine the fate of the 166Ho-chitosan complex (DW-166HC) in rats by examining its absorption, distribution and excretion after administration into the prostate. METHODS: About 100 microCi of DW-166HC [containing 0.1875 mg of Ho(NO3)3.5H2O and 0.25 mg of chitosan] was administered intraprostatically. The level of radioactivity in blood, urinary and faecal excretion, and radioactivity distribution were examined. To determine the effect of chitosan in DW-166HC, 166Ho nitrate alone [0.1875 mg of Ho(NO3)3.5H2O] was administered into the prostate of male rats, and radioactivity distribution was examined using whole-body autoradiography. RESULTS: After administration of DW-166HC into the prostate, cumulative urinary and faecal excretion over the period 0-72 h was 0.35% and 0.11%, respectively. The radioactivity at the administration site was extremely high at all time points up to 144 h (>98% of injected dose). The small amount of radioactivity which did transfer from the administration site distributed mainly to the liver, spleen, kidney cortex and bone. Compared with the DW-166HC group, the group that received 166Ho nitrate alone displayed three- to fourfold higher levels of radioactivity in the main tissues, including liver, spleen, kidney cortex and bone, at 24 h after administration (P < 0.05). CONCLUSION: The results of this study show clearly that most of the administered DW-166HC remained at the administration site. It is concluded that the chitosan complex may be used to retain 166Ho within a limited area in cancer of the prostate.

Release of triamcinolone acetonide from mucoadhesive polymer composed of chitosan and poly(acrylic acid) in vitro.

Transmucosal drug delivery (TMD) system using mucoadhesive polymer has been recently interested due to the rapid onset of action, high blood level, avoidance of the first-pass effect and the exposure of the drug to the gastrointestinal tract. A novel mucoadhesive polymer complex composed of chitosan and poly(acrylic acid) (PAA) was prepared by template polymerization of acrylic acid in the presence of chitosan for the TMD system. Triamcinolone acetonide (TAA) was loaded into the chitosan/PAA polymer complex film. TAA was evenly dispersed in chitosan, PAA polymer complex film without interaction with polymer complex. Release behavior of TAA from the mucoadhesive polymer film was dependent on time, pH, loading content of drug, and chitosan PAA ratio. The analysis of the drug release from the mucoadhesive film showed that TAA might be released from the chitosan/PAA polymer complex film through non-Fickian diffusion mechanism.