Design, synthesis and biological evaluations of a long-acting, hypoxia-activated prodrug of fasudil, a ROCK inhibitor, to reduce its systemic side-effects.

ROCK, one of the downstream regulators of Rho, controls actomyosin cytoskeleton organization, stress fiber formation, smooth muscle contraction, and cell migration. ROCK plays an important role in the pathologies of cerebral and coronary vasospasm, hypertension, cancer, and arteriosclerosis. Pharmacological-induced systemic inhibition of ROCK affects both the pathological and physiological functions of Rho-kinase, resulting in hypotension, increased heart rate, decreased lymphocyte count, and eventually cardiovascular collapse. To overcome the adverse effects of systemic ROCK inhibition, we developed a bioreductive prodrug of a ROCK inhibitor, fasudil, that functions selectively under hypoxic conditions. By masking fasudil's active site with a bioreductive 4-nitrobenzyl group, we synthesized a prodrug of fasudil that is inactive in normoxia. Reduction of the protecting group initiated by hypoxia reveals an electron-donating substituent that leads to fragmentation of the parent molecule. Under normoxia the fasudil prodrug displayed significantly reduced activity against ROCK compared to its parent compound, but under severe hypoxia the prodrug was highly effective in suppressing ROCK activity. Under hypoxia the prodrug elicited an antiproliferative effect on disease-afflicted pulmonary arterial smooth muscle cells and pulmonary arterial endothelial cells. The prodrug displayed a long plasma half-life, remained inactive in the blood, and produced no drop in systemic blood pressure when compared with fasudil-treated controls. Due to its selective nature, our hypoxia-activated fasudil prodrug could be used to treat diseases where tissue-hypoxia or hypoxic cells are the pathological basis of the disease.

Efficacy of fasudil for the treatment of aneurysmal subarachnoid hemorrhage: A systematic review protocol of randomized controlled trial.

BACKGROUND: This study aims to systematically assess the efficacy and safety of fasudil for the treatment of aneurysmal subarachnoid hemorrhage (ASH). METHODS: This study will include all of randomized controlled trials on the efficacy and safety of fasudil for the treatment of ASH. Ten electronic databases of PubMed, Embase, Cochrane Library, Google Scholar, Web of Science, Ovid, Cumulative Index to Nursing and Allied Health Literature, Allied and Complementary Medicine Database, Chinese Biomedical Literature Database, and China National Knowledge Infrastructure will be searched from inception to the May 1, 2019 without language restrictions. We will also search gray literatures to avoid missing any other potential studies. Two authors will independently perform study selection, data extraction and management, and methodologic quality assessment. The primary outcome is limbs function. The secondary outcomes comprise of muscle strength, muscle tone, quality of life, and adverse events. RESULTS: This study will provide a comprehensive literature search on the current evidence of fasudil for the treatment of ASH from primary and secondary outcomes. CONCLUSION: The results of this study will present evidence to determine whether fasudil is an effective and safety treatment for patients with ASH. SYSTEMATIC REVIEW REGISTRATION: PROSPERO CRD42019136215.

Fasudil combined with methylcobalamin or lipoic acid can improve the nerve conduction velocity in patients with diabetic peripheral neuropathy: A meta-analysis.

BACKGROUND: Fasudil (F) plus methylcobalamin (M) or lipoic acid (L) treatment has been suggested as a therapeutic approach for diabetic peripheral neuropathy (DPN) in numerous studies. However, the effect of the combined use still remains dubious. OBJECTIVE: The aim of this report was to evaluate the efficacy of F plus M or L (F + M or F + L) for the treatment of DPN compared with that of M or L monotherapy, respectively, in order to provide the basis and reference for clinical rational drug use. METHODS: Randomized controlled trials (RCTs) of F for DPN published up to September 2017 were searched. Relative risk (RR), mean difference (MD), and 95% confidence interval (CI) were calculated and heterogeneity was assessed with the I test. Sensitivity analyses were also performed. The outcomes measured were as follows: the clinical efficacy, median motor nerve conduction velocities (NCVs) (MNCVs), median sensory NCV (SNCV), peroneal MNCV, peroneal SNCV, and adverse effects. RESULTS: Thirteen RCTs with 1148 participants were included. Clinical efficacy of F + M combination therapy was significantly better than M monotherapy (8 trials; RR 1.26, 95% CI 1.17-1.35, P < .00001, I = 0%), the efficacy of F + L combination therapy was also obviously better than L monotherapy (4 trials; RR 1.27, 95% CI 1.16-1.39, P < .00001, I = 0%). Compared with monotherapy, the pooled effects of combination therapy on NCV were (MD 6.69, 95% CI 4.74-8.64, P < .00001, I = 92%) for median MNCV, (MD 6.71, 95% CI 1.77-11.65, P = .008, I = 99%) for median SNCV, (MD 4.18, 95% CI 2.37-5.99, P < .00001, I = 94%) for peroneal MNCV, (MD 5.89, 95% CI 3.57-8.20, P < .00001, I = 95%) for peroneal SNCV. Furthermore, there were no serious adverse events associated with drug intervention. CONCLUSION: Combination therapy with F plus M or L was superior to M or L monotherapy for improvement of neuropathic symptoms and NCVs in DPN patients, respectively. Moreover, no serious adverse events occur in combination therapy.

Effects of fasudil on pulmonary hypertension in clinical practice.

Pulmonary hypertension (PH) is a pathophysiologic disorder that may involve multiple clinical conditions and can complicate the majority of cardiovascular and respiratory diseases. The presence of PH is associated with worse outcomes, but the efficacy of current therapy is still unsatisfactory. Because Rho-kinase (ROCK) plays an important role in the pathogenesis of PH, the ROCK inhibitor fasudil is expected to contribute to PH treatment. In animal models of PH, fasudil reduced pulmonary artery pressure (PAP) and improved survival. Furthermore, the short-term efficacy and safety of fasudil in the treatment of PH are demonstrated in clinical trials. Both PAP and pulmonary vascular resistance in patients with PH are significantly decreased by intravenous or inhaled fasudil without apparent side effect. However, no clinical trial has assessed the long-term efficacy of fasudil in the treatment of PH. Limited data suggest that the mid-term use of fasudil could improve exercise capacity and reduce in-hospital mortality. We also discuss the combined use of fasudil and other drugs for PH treatment. However, these combinations have not yet been evaluated in a clinical trial. According to animal studies, the combination of fasudil with beraprost or sildenafil shows synergistic effects, whereas the combination of fasudil with bosentan has no additional ameliorating effects on PH development.

Nano-engineered erythrocyte ghosts as inhalational carriers for delivery of fasudil: preparation and characterization.

PURPOSE: Nanoerythrosomes (NERs), an engineered derivative of erythrocytes, have long been used as drug delivery carriers. These cell based carriers are biocompatible and biodegradable, and they exhibit efficient drug loading, targeting specificity and prolonged biological half-life. In this study, we have evaluated the feasibility of NERs as inhalable carriers for delivery of fasudil, an investigational drug for the treatment of pulmonary arterial hypertension. METHODS: We prepared NERs by hypotonic lysis of erythrocytes derived from rat blood followed by extrusion through polycarbonate membranes. The formulations were optimized and characterized for size, morphology, entrapment efficiency, stability, cellular uptake and in-vitro release profiles followed by monitoring of drug absorption and safety evaluation after intratracheal administration of fasudil-loaded NERs into rats. RESULTS: NERs were spherical in shape with an average size of 154.1 ± 1.31 nm and the drug loading efficiency was 48.76 ± 2.18%. Formulations were stable when stored at 4°C for 3 weeks. When incubated with rat pulmonary arterial smooth muscle cells (PASM), a significant amount of NERs was taken up by PASM cells. The drug encapsulated in NERs inhibited the rho-kinase activity upto 50%, which was comparable with the plain fasudil. A ~6-8 fold increase in the half-life of fasudil was observed when encapsulated in NERs. CONCLUSION: This study suggests that nanoerythrosomes can be used as cell derived carriers for inhalational delivery of fasudil.

Clinical investigation of fasudil for the prevention of cerebral vasospasm in extracranial carotid artery stenting.

To evaluate fasudil hydrochloride for the prevention of cerebral vasospasm (CVS) in extra-cranial carotid angioplasty and stenting (CAS). We retrospectively analyzed 178 patients with unilateral CAS who were given intravenous fasudil hydrochloride during the perioperative period. CVS, hypotension, stroke, and mortality incidence rates were recorded. Of the cohort studied, 80.9 % patients exhibited no local CVS, asymptomatic vasospasm was observed in 17.4 % patients and symptomatic vasospasm in 1.7 % patients via DSA imaging. All CVS was relieved and symptoms disappeared after intra-arterial infusion of papaverine hydrochloride. Intracerebral hemorrhage occurred in two cases during the perioperative period, one of which resulted in death. CVS is a severe complication of CAS. Fasudil hydrochloride can rapidly relieve cerebral vasospasm, has no selective effect on cerebral vasculature, and little influence on blood pressure. It is suitable for the prevention of CVS during interventional treatment of ischemic cerebrovascular disease.

Efficacy and safety of fasudil in patients with subarachnoid hemorrhage: final results of a randomized trial of fasudil versus nimodipine.

Fasudil is believed to be at least equally effective as nimodipine for the prevention of cerebral vasospasm and subsequent ischemic injury in patients undergoing surgery for subarachnoid hemorrhage (SAH). We report the final results of a randomized, open trial to compare the efficacy and safety of fasudil with nimodipine. A total of 63 patients undergoing surgery for SAH received fasudil and 66 received nimodipine between 1998 and 2004. Symptomatic vasospasm, low density areas on computed tomography (CT), clinical outcomes, and adverse events were all recorded, and the results were compared between the fasudil and nimodipine groups. Absence of symptomatic vasospasm, occurrence of low density areas associated with vasospasm on CT, and occurrence of adverse events were similar between the two groups. The clinical outcomes were more favorable in the fasudil group than in the nimodipine group (p = 0.040). The proportion of patients with good clinical outcome was 74.5% (41/55) in the fasudil group and 61.7% (37/60) in the nimodipine group. There were no serious adverse events reported in the fasudil group. The present results suggest that fasudil is equally or more effective than nimodipine for the prevention of cerebral vasospasm and subsequent ischemic injury in patients undergoing surgery for SAH.

Vasodilatation produced by fasudil mesylate in vivo and in vitro.

To investigate the vasorelaxant effect of fasudil mesylate (FM) in vivo and in vitro. The relaxation effect of FM was studied using cerebral vasospasm (CVS) model in vivo and isolated aortic rings in vitro. FM (0.35, 1.2, 3.5 mg·kg⁻¹) increased cerebrovascular flow (CVF) and femoral blood flow (FBF) dose-dependently in vivo, however, the relaxation effects of FM on cerebral vessels were much stronger than on peripheral vessels; FM showed dose-dependent relaxation of isolated aortic rings contracted by Methoxamine (Met) or KCl in vitro. The relaxation IC50 of FM and Prasozin (Pra) to the rabbit aortic rings contracted by Met are 27.54 µM and 0.01 µM respectively, and the relaxation IC50 of FM to the rabbit and rat aortic rings contracted by KCl are 37.15 µM and 0.74 µM respectively. In addition, there is no obvious difference between endothelium-intact and endothelium-removal groups. The Met dose-effect relationship curve was significantly shifted to right by FM (0.3, 3 µM), and E(max) was decreased (P<0.05). The relaxation effect of FM on cerebral vessels was much stronger than on peripheral vessels in vivo, and the action is in an endothelium-independent manner.

Convulsion during intra-arterial infusion of fasudil hydrochloride for the treatment of cerebral vasospasm following subarachnoid hemorrhage.

The incidence of convulsion and associated factors were retrospectively analyzed in 23 patients with symptomatic cerebral vasospasm following subarachnoid hemorrhage (SAH) who underwent a total of 31 intra-arterial infusion of fasudil hydrochloride (IAFH) procedures in 49 vessels. Fasudil hydrochloride was administered by superselective infusion via a microcatheter positioned at the proximal portion of the affected artery. Thirteen procedures were performed by manually controlled infusion of 30-75 mg fasudil hydrochloride (1.2-3.75 mg/ml) for approximately 10 minutes. Eighteen procedures were performed by continuous infusion of 60 mg fasudil hydrochloride (1.2 mg/ml) by infusion pump at a constant rate of 3 mg/min. Neurological improvement was observed after 18 of 22 procedures in patients with neurological deterioration due to vasospasm. Convulsion during IAFH developed in 4 patients, all treated by manual infusion (p < 0.05). The manual infusion method (p < 0.05) and infusion rate greater than 3 mg/min (p < 0.01) were significantly associated with the incidence of convulsion during IAFH. IAFH was effective for treating cerebral vasospasm following aneurysmal SAH. IAFH at a constant rate of 3 mg/min delivered by infusion pump improved the symptoms of cerebral vasospasm and prevented convulsions during IAFH.

The effect of the Rho-associated protein kinase inhibitor, HA-1077, in the rabbit ocular hypertension model induced by water loading.

PURPOSE: The aim of this study was to investigate the intraocular pressure (IOP)-lowering effect of a new anti-glaucoma drug, the Rho-associated protein kinase (ROCK) inhibitor, HA-1077, in a rabbit ocular hypertension model. METHODS: Experiments were carried out in 18 male New Zealand white rabbits, with ocular hypertension induced by water loading. Animals were divided into three groups followed by topical administration of 1 mM, 2 mM, and 3 mM HA-1077 in the left eye. As a control, phosphate buffered saline was administered in the opposite eye. RESULTS: After administration of HA-1077 eye drops, there was a significant time- and dose-dependent decrease of the IOP. While minor conjunctival injection was seen in a few cases, no abnormalities of the anterior chamber or fundus were observed. CONCLUSIONS: This is the first report of the effect of the ROCK inhibitor, HA-1077, on the IOP in an ocular hypertension model. Study results indicated that HA-1077 has a strong IOP-lowering effect.

Importance of Rac1 signaling pathway inhibition in the pleiotropic effects of HMG-CoA reductase inhibitors.

BACKGROUND: The pleiotropic effects of HMG-CoA reductase inhibitors (statins) are thought to be mediated through inhibition of small GTP-binding proteins; however, it remains to be examined whether clinical concentrations/doses of statins actually exert them. METHODS AND RESULTS: In vitro studies with cultured human umbilical venous endothelial cells found that statins (atorvastatin, pitavastatin and pravastatin at 10 micromol/L) had no inhibitory effects on RhoA/Rho-kinase or Ras, but atorvastatin and pitavastatin inhibited membrane Rac1 expression. In animal studies of angiotensin II (AngII)-infused rats, atorvastatin showed only mild inhibitory effects on AngII-induced cardiovascular hypertrophy, whereas fasudil, a selective Rho-kinase inhibitor, significantly suppressed it. Statins had no inhibitory effects on RhoA/Rho-kinase, but inhibited both membrane and GTP-bound Rac1 in the heart, whereas fasudil only inhibited Rho-kinase activity. Furthermore, the combination of atorvastatin and fasudil showed more effective inhibitory effects than fasudil alone. Finally, in studies of normal healthy volunteers, clinical doses of pravastatin or atorvastatin (20 mg/day for 1 week) significantly inhibited Rac1, but not RhoA/Rho-kinase activity, in circulating leukocytes. CONCLUSIONS: The pleiotropic effects of statins, if any, at their clinical doses are mediated predominantly through inhibition of the Rac1 signaling pathway.

In vivo dilatation of the ductus arteriosus by Rho kinase inhibition in the rat.

BACKGROUND: Fasudil hydrochloride, a Rho kinase inhibitor, was reported to dilate the constricted ductus arteriosus in vitro, and was suggested as a neonatal bridge to heart surgery. OBJECTIVES: To clarify the in vivo effectiveness of fasudil to dilate the neonatal ductus arteriosus, and its usefulness as a bridge to heart surgery. METHODS: We studied the dose and timing of administration of fasudil in the neonatal rat. Postnatal ductal closure was studied on the 21st gestational day following cesarean section and incubation for 30-480 min in room air at 33 degrees C, with a rapid whole-body freezing method. In control rats, the ductus closed rapidly after birth, and the ductal diameter was 0.80 and 0.12 mm at 0 and 30 min after birth. Fasudil was injected peritoneally into the neonate, and the ductus was studied 30 min after injection and 60 min after birth. RESULTS: Fasudil, 10 mg/kg, injected within 5 min after birth, dilated the ductus completely to 0.8 mm, and the dose used clinically, 1 mg/kg, dilated the ductus to 0.4 mm. The ductus-dilating effect of fasudil decreased rapidly as the neonatal ductus constricted. Fasudil, 100 mg/kg, dilated the ductus completely, but induced severe respiratory depression and frequent death in 1-hour-old rats. CONCLUSIONS: Fasudil dilates the neonatal ductus arteriosus dose-dependently in the rat. Fasudil in large doses dilates the neonatal ductus completely, but is associated with fatal side effects, including respiratory depression.

Safety and efficacy of fasudil monotherapy and fasudil-ozagrel combination therapy in patients with subarachnoid hemorrhage: sub-analysis of the post-marketing surveillance study.

Sub-analysis of the fasudil post-marketing surveillance study compared the safety and efficacy of fasudil plus ozagrel to fasudil only. A total of 3690 patients received fasudil and 1138 received fasudil plus ozagrel between 1995 and 2000. The occurrence of adverse events, occurrence of low density areas associated with vasospasm on computed tomography, absence of symptomatic vasospasm, and poor clinical outcomes associated with vasospasm were compared between the fasudil and fasudil plus ozagrel groups. The pharmacokinetics of fasudil were assessed in 5 patients with subarachnoid hemorrhage. The drug interaction between fasudil and ozagrel was pharmacologically investigated in vitro and in vivo. The occurrence of adverse events and clinical outcomes were similar between the two groups. The occurrences of symptomatic vasospasm and low density areas were lower in the fasudil group than in the fasudil plus ozagrel group. The average trough value (8-hour value) of the fasudil active metabolite, hydroxyfasudil, was 50 nM. Fasudil showed no pharmacological interaction with ozagrel. The combination of fasudil plus ozagrel was well tolerated, but did not result in better efficacy than fasudil only.

A postmarketing surveillance study of fasudil treatment after aneurysmal subarachnoid hemorrhage.

BACKGROUND: The aim of the present study was, first, to assess safety of fasudil (Eril; Asahi Kasei Pharma Corp, Tokyo, Japan) and, second, to investigate whether the effects of fasudil in the phase 3 trial could be reproduced in a PMS study. METHODS: Between 1995 and 2000, a total of 1462 patients met the eligibility criteria of the phase 3 trial and were treated with fasudil in a PMS study. Adverse events, low-density areas on CT scans, symptomatic vasospasm, and clinical outcome were all recorded. The results were compared with those in the phase 3 trial. Patients with Fisher grade 3 on admission were selected (subgroup), and the results were also compared with those in the phase 3 trial. RESULTS: The occurrence of adverse events, including intracranial bleeding and hypotension, low-density areas, and clinical outcomes were similar between the fasudil-treated patients in the phase 3 trial and the patients in the PMS study. The absence of symptomatic vasospasm was more common in the PMS study than in the phase 3 trial. Of the 1462 patients, 842 met the criteria for the subgroup. In the subgroup, the occurrence of low-density areas, the absence of symptomatic vasospasm, and clinical outcomes were similar between the fasudil-treated patients in the phase 3 trial and the patients in the PMS study. CONCLUSIONS: The present PMS study described the tolerability, safety, and efficacy of fasudil in a large number of patients undergoing surgery for SAH, as demonstrated previously in the phase 3 trial.

Effects of fasudil in acute ischemic stroke: results of a prospective placebo-controlled double-blind trial.

BACKGROUND: A multicenter, double-blind, placebo-controlled study was conducted to assess the efficacy and safety of fasudil, a Rho-kinase inhibitor (RKI), in the treatment of acute ischemic stroke. METHODS: A total of 160 patients, who were able to receive drug treatment within 48 h of acute ischemic stroke onset were enrolled. Patients received either 60 mg fasudil or a placebo (saline) by intravenous injection over 60 min, twice daily for 14 days. The primary end points were neurological status at 2 weeks after the start of treatment, and clinical outcome at 1 month after the onset of symptoms. RESULTS: Fasudil treatment resulted in significantly greater improvements in both neurological functions (p=0.0013), and clinical outcome (p=0.0015). There were no serious adverse events reported in the fasudil group. The average trough value (12 h values) of active metabolite hydroxyfasudil, another RKI, in healthy elderly volunteers receiving 60 mg of fasudil was 0.077 microM-a concentration well above that needed to inhibit Rho-kinase (0.025-0.05 microM). CONCLUSION: Treatment with fasudil within 48 h of acute ischemic stroke onset significantly improved the patient's clinical outcome. This study found fasudil to be a useful and safe drug for patients with acute ischemic stroke. Further evaluations, for example, 3-month functional outcomes in a larger clinical trial, may help to define the efficacy of fasudil in acute ischemic stroke.

[A case of convulsion during selective intra-arterial infusion of fasudil hydrochloride for treatment of vasospasm following subarachnoid hemorrhage].

The authors report a case of convulsion during intra-arterial selective infusion of fasudil hydrochloride (FSD) for treatment of vasospasm following subarachnoid hemorrhage (SAH). A 47-year-old man (Hunt and Kosnik grade I) presented with sudden onset of headache and was diagnosed with SAH on CT, and admitted to our hospital. Digital subtraction angiography (DSA) performed on admission revealed an anterior communicating artery aneurysm. Neck clipping of the aneurysm was performed on the same day and no neurological deficits were noted postoperatively. Motor aphasia appeared on day 11 after the operation, and emergency DSA revealed vasospasm of the left middle cerebral artery and its branches. Emergency percutaneous transluminal angioplasty was performed with successful dilation of the left M1 artery, and 25 milligrams of FSD was injected into the left M1 artery selectively. During this injection, right hemifacial convulsion appeared, and three minutes later disappeared. No treatment was needed for the seizure. Additional injection of 30 milligrams of FSD into the left internal carotid artery resulted in vasodilatation of the left M1 artery and its branches, improvement of their blood flow on angiography, and recovery from motor aphasia. The patient was discharged 1 month later with no neurological deficits. Intra-arterial selective infusion of FSD plays an important role in treatment for vasospasm following SAH, however, we must be aware of risks of complications such as convulsion.

Combination therapy of fasudil hydrochloride and ozagrel sodium for cerebral vasospasm following aneurysmal subarachnoid hemorrhage.

Fasudil hydrochloride is a new type of intracellular calcium antagonist, different from the calcium entry blockers that are commonly employed for clinical use. Since September 1995, the combination of fasudil hydrochloride and ozagrel sodium, an inhibitor of thromboxane A2 synthesis, has been used to treat 60 patients at risk of cerebral vasospasm after aneurysmal subarachnoid hemorrhage. The effectiveness of this combination therapy was investigated by comparison with the outcome of 57 patients previously treated with only ozagrel sodium. The combination therapy was significantly more effective (p < 0.01) in reducing the incidence of low density areas on computed tomography scans, and reduced, but not significantly, the occurrence of symptomatic vasospasm. The combination therapy of fasudil hydrochloride and ozagrel sodium has superior effectiveness over only ozagrel sodium in treating patients at risk of vasospasm after aneurysmal subarachnoid hemorrhage.