SIRT1: A Potential Therapeutic Target in Autoimmune Diseases.

The morbidity and mortality of autoimmune diseases (Ads) have been increasing worldwide, and the identification of novel therapeutic strategies for prevention and treatment is urgently needed. Sirtuin 1 (SIRT1), a member of the class III family of nicotinamide adenine dinucleotide (NAD+)-dependent histone deacetylases, has been reported to participate in the progression of several diseases. SIRT1 also regulates inflammation, oxidative stress, mitochondrial function, immune responses, cellular differentiation, proliferation and metabolism, and its altered functions are likely involved in Ads. Several inhibitors and activators have been shown to affect the development of Ads. SIRT1 may represent a novel therapeutic target in these diseases, and small molecules or natural products that modulate the functions of SIRT1 are potential therapeutic agents. In the present review, we summarize current studies of the biological functions of SIRT1 and its role in the pathogenesis and treatment of Ads.

Efficacy and safety of riociguat in the treatment of chronic thromboembolic pulmonary arterial hypertension: A meta-analysis.

BACKGROUND: Riociguat is a novel soluble guanylate cyclase stimulator, and has been widely used for the treatment of pulmonary arterial hypertension and chronic thromboembolic pulmonary hypertension (CTEPH). Some studies found that riociguat had better effects on CTEPH and proved to be safe, but the results were not utterly consistent. Therefore, the purpose of this study was to comprehensively evaluate the efficacy and safety of riociguat in the treatment of CTEPH. METHODS: Randomized controlled trials on riociguat for the treatment of CTEPH were searched through such electronic databases as PubMed, Embase, Cochrane Library, Web of Science, China national knowledge internet, and Wanfang. The outcomes included exercise capacity, pulmonary hemodynamics, and side effects. The fixed-effects or random-effects models were used to analyze the pooled data, and heterogeneity was assessed by the I2 test. RESULTS: Four studies involving 520 patients were included in this meta-analysis. Compared with the placebo group, riociguat significantly improved the hemodynamic indexes and increased 6-min walking distance (P < .0001, standardized mean difference (SMD) = -0.24, 95%CI -0.35 to -0.12; P < .00001, SMD = 0.52, 95%CI 0.33 to 0.71), and decreased the Borg dyspnea score (P = .002, SMD = -0.31, 95%CI -0.51 to -0.12). In addition, riociguat could also significantly reduce the living with pulmonary hypertension scores and increase the EQ-5D scores (P = .01, SMD=-0.23, 95%CI -0.42 to -0.05; P < .00001, SMD = 0.47, 95%CI 0.27 to 0.66), but there was no significant difference in the change level of N-terminal pro-hormone B-type natriuretic peptide in patients with riociguat (P = .20, SMD = -0.24, 95%CI -0.61 to -0.13). The common adverse events of riociguat were dyspepsia and peripheral edema, and no other serious adverse reactions were observed. CONCLUSIONS: We confirmed that riociguat had better therapeutic effects in improving the hemodynamic parameters and exercise capacity in patients with CTEPH without inducing serious adverse events. This will provide a reasonable medication regimen for the treatment of CTEPH.

Pulmonary arterial hypertension in the emergency department: A focus on medication management.

Pulmonary arterial hypertension (PAH) is a chronic progressive incurable condition associated with a high degree of morbidity and mortality. With over five drug classes FDA approved in the last decade, the significant advancements in the pharmacologic management of PAH has improved long-term outcomes. Drug therapies have been developed to directly target the underlying pathogenesis of PAH including phosphodiesterase type-5 inhibitors (PDE-5i), endothelin-receptor antagonists (ERAs), guanylyl-cyclase inhibitors, prostacyclin analogues, and prostacyclin receptor agonists. Although these agents offer remarkable benefits, there are significant challenges with their use such as complexities in medication dosing, administration, and adverse effects. Given these consequences, PAH medications are classified as high-risk, and the transitions of care process to and from the hospital setting are a vulnerable area for medication errors in this population. Thus, it is crucial for the emergency department provider to appropriately identify, manage, and triage these patients through close collaboration with a multidisciplinary team to ensure safe and effective medication management for PAH patients in the acute care setting.

The potential actions of angiotensin-converting enzyme II (ACE2) activator diminazene aceturate (DIZE) in various diseases.

The renin angiotensin system (RAS) regulates fluid balance, blood pressure and maintains vascular tone. The potent vasoconstrictor angiotensin II (Ang II) produced by angiotensin-converting enzyme (ACE) comprises the classical RAS. The non-classical RAS involves the conversion of Ang II via ACE2 into the vasodilator Ang (1-7) to counterbalance the effects of Ang II. Furthermore, ACE2 converts AngA into another vasodilator named alamandine. The over activation of the classical RAS (increased vasoconstriction) and depletion of the non-classical RAS (decreased vasodilation) results in vascular dysfunction. Vascular dysfunction is the leading cause of atherosclerosis and cardiovascular disease (CVD). Additionally, local RAS is expressed in various tissues and regulates cellular functions. RAS dysregulation is involved in other several diseases such as inflammation, renal dysfunction and even cancer growth. An approach in restoring vascular dysfunction and other pathological diseases is to either increase the activity of ACE2 or reduce the effect of the classical RAS by counterbalancing Ang II effects. The antitrypanosomal agent, diminazene aceturate (DIZE), is one approach in activating ACE2. DIZE has been shown to exert beneficial effects in CVD experimental models of hypertension, myocardial infarction, type 1 diabetes and atherosclerosis. Thus, this review focuses on DIZE and its effect in several tissues such as blood vessels, cardiac, renal, immune and cancer cells.

Targeting NAMPT as a therapeutic strategy against stroke.

Stroke is the second and the leading most common cause of death in the world and China, respectively, but with few effective therapies. Nicotinamide phosphoribosyltransferase (NAMPT) is the rate-limiting enzyme for nicotinamide adenine dinucleotide (NAD) salvage synthesis in mammals, thereby influencing NAD-dependent enzymes and constituting a strong endogenous defence system against various stresses. Accumulating in-vitro and in-vivo studies have demonstrated the neuroprotective effect of NAMPT in stroke. Here, we review the direct evidence of NAMPT as a promising target against stroke from five potential therapeutic strategies, including NAMPT overexpression, recombinant NAMPT, NAMPT activators, NAMPT enzymatic product nicotinamide mononucleotide (NMN), and NMN precursors nicotinamide riboside and nicotinamide, and describe the relevant mechanisms and limitations, providing a promising choice for developing novel and effective therapeutic interventions against ischaemic and haemorrhagic stroke.

The efficacy and safety of soluble guanylate cyclase stimulators in patients with heart failure: A systematic review and meta-analysis.

BACKGROUND: Several randomized controlled trials (RCTs) have been investigated the benefits of soluble guanylate cyclase (sGC) stimulators in the treatment of heart failure, but a comprehensive evaluation is lacking. We performed a meta-analysis to evaluate the efficacy and safety of oral sGC stimulators (vericiguat and riociguat) in patients with heart failure. METHODS: Studies were searched and screened in PubMed, Embase, and Cochrane Library. Eligible RCTs were included that reported mortality, the change of EuroQol Group 5-Dmensional Self-report Questionnaire (EQ-5D) US index, N-terminal pro-B-type natriuretic peptide (NT-proBNP), or serious adverse events (SAEs). Relative risk or weight mean difference (WMD) was estimated using fixed effect model or random effect model. Analysis of sensitivity and publication bias was conducted. RESULTS: Five trials with a total of 1200 patients were included. sGC stimulators had no impact on the mortality (1.25; 95% confidence interval 0.50-3.11) and significantly improved EQ-5D US index (0.04; 95% confidence interval 0.020-0.05). Furthermore, in comparison with control group, NT-proBNP was statistically decreased in riociguat group (-0.78; 95% confidence interval -1.01 to -0.47), but not in vericiguat group (0.04, 95% confidence interval -0.18 to 0.25). There were not obverse differences in SAEs between sGC stimulators and control groups (0.90; 95% confidence interval 0.72-1.12). CONCLUSION: Our meta-analysis suggests that sGC stimulators could improve the quality of life in patients with heart failure with good tolerance and safety, but their long-term benefits need to be observed in the future. sGC stimulators are likely to be promising add-on strategies for the treatment of heart failure.

Initial Riociguat Monotherapy and Transition from Sildenafil to Riociguat in Patients with Idiopathic Pulmonary Arterial Hypertension: Influence on Right Heart Remodeling and Right Ventricular-Pulmonary Arterial Coupling.

PURPOSE: To evaluate the influence of riociguat on World Health Organization functional class (WHO FC), 6-min walk distance (6MWD), right heart remodeling, and right ventricular-pulmonary arterial (RV-PA) coupling in patients with idiopathic pulmonary arterial hypertension (IPAH) who are treatment-naïve or who have failed to achieve treatment goals with sildenafil therapy. METHODS: Twenty patients with IPAH were enrolled: 12 had not previously received PAH-targeted therapy (treatment-naïve subgroup) and 8 had been receiving sildenafil therapy but failed to achieve treatment goals; on entering this pilot study these 8 patients were switched from sildenafil to riociguat therapy (treatment-switch subgroup). Patients received riociguat individually dose-adjusted up to a maximum of 2.5 mg three times daily. After 12 weeks, patients were assessed for WHO FC, 6MWD, right heart remodeling, and RV-PA coupling. RESULTS: Riociguat significantly improved WHO FC in treatment-naïve patients (from 0/4/8/0 patients in WHO I/II/III/IV at baseline to 1/6/5/0 at week 12) and in treatment-switch patients (from 0/4/4/0 patients in WHO I/II/III/IV at baseline to 1/4/3/0 at week 12). Additionally, treatment-naïve and treatment-switch patients showed significant improvements at week 12 versus baseline in 6MWD (increases of + 76.8 m and + 71.6 m, respectively), RV systolic function, and RV-PA coupling. CONCLUSION: These results support the proven efficacy of riociguat in patients with IPAH, including treatment-naïve patients and those switching to riociguat following failure to achieve treatment goals with sildenafil, and suggest that it may be possible to delay disease progression in this patient group.

Clinically Worsening Chronic Thromboembolic Pulmonary Hypertension by Riociguat After Balloon Pulmonary Angioplasty.

Riociguat, a soluble guanylate cyclase stimulator, induces pulmonary artery dilatation through blood flow and is effective in treating chronic thromboembolic pulmonary hypertension (CTEPH). There are two types of vasculopathies in CTEPH based upon its location, in other words, proximal or distal to the thrombus-medicated obstruction. Distal vasculopathy is characterized by intrapulmonary shunts due to diminished blood flow. While other therapeutic interventions for CTEPH including pulmonary endarterectomy and balloon pulmonary angioplasty achieve reperfusion to the distal vasculopathy vessels, the effects of riociguat on distal vasculopathy vessels remain undetermined. Herein, we describe a case of a 66-year-old woman who exhibited deterioration of mean pulmonary artery pressure and exercise tolerance after a 4-month treatment with riociguat. She received balloon pulmonary angioplasty prior to riociguat administration. Her lung perfusion scintigraphy and pulmonary angiography findings did not change over the course of treatment. Notably, after the discontinuation of riociguat, her clinical values returned to their levels prior to riociguat administration. Her intrapulmonary shunt ratio followed a similar course as her hemodynamic status. We demonstrate that riociguat can deteriorate hemodynamic status, which may mediate the dilatation of intrapulmonary shunts. We should perform close monitoring of symptoms and hemodynamic status after riociguat administration, especially in patients in whom the reperfused DVs occurred due to invasive treatment.

A Randomized, Controlled Phase I/II Study to Evaluate the Safety and Efficacy of MGV354 for Ocular Hypertension or Glaucoma.

PURPOSE: To assess the clinical safety, tolerability, and efficacy of topically administered MGV354, a soluble guanylate cyclase (sGC) activator, in patients with ocular hypertension (OH) or glaucoma. DESIGN: Double-masked, randomized, and vehicle-controlled study. METHODS: Parts 1 and 2 evaluated safety and tolerability to identify the maximum tolerated dose (MTD) of once-daily MGV354 in 32 healthy volunteers (Part 1) and 16 patients with OH or glaucoma (Part 2) at a single clinical site. Part 3 was a multisite trial that evaluated intraocular pressure (IOP)-lowering efficacy of the MTD administered nightly for 1 week in 50 patients with minimum IOP of 24 mm Hg at 8 AM, with a main outcome measure of mean diurnal IOP at day 8 compared to baseline (ClinicalTrials.govNCT02743780). RESULTS: There was no difference in favor of MGV354 for IOP lowering; change from baseline to day 8 in mean diurnal IOP was -0.6 mm Hg for MGV354-treated patients and -1.1 mm Hg for vehicle-treated patients in Part 3, with a confidence interval of -0.7 to 1.7. The most common adverse events reported after MGV354 administration were conjunctival and ocular hyperemia. CONCLUSIONS: Overall, MGV354 0.1% demonstrated no statistically significant effect compared to vehicle in lowering IOP based on the study's main outcome measure. MGV354 produced ocular hyperemia consistent with its pharmacology.

Omecamtiv Mecarbil: A Myosin Motor Activator Agent with Promising Clinical Performance and New in vitro Results.

BACKGROUND: Clinical treatment of heart failure is still suffering from limited efficacy and unfavorable side effects. The recently developed group of agents, the myosin motor activators, act directly on cardiac myosin resulting in an increased force generation and prolongation of contraction. The lead molecule, omecamtiv mecarbil is now in human 3 stage. In addition to the promising clinical data published so far, there are new in vitro results indicating that the effect of omecamtiv mecarbil on contractility is rate-dependent. Furthermore, omecamtiv mecarbil was shown to activate cardiac ryanodine receptors, an effect that may carry proarrhythmic risk. METHODS: These new results, together with the controversial effects of the drug on cardiac oxygen consumption, are critically discussed in this review in light of the current literature on omecamtiv mecarbil. RESULTS: In therapeutically relevant concentrations the beneficial inotropic effect of the agent is not likely affected by these new results - in accordance with the good clinical data. At supratherapeutic concentrations, however, activation of cardiac ryanodine receptors may increase arrhythmia propensity, and the stronger effect on diastolic than systolic cell shortening, observed at higher pacing frequencies, may decrease or offset the inotropic effect of omecamtiv mecarbil. CONCLUSION: Further studies with definitely supratherapeutical concentrations of omecamtiv mecarbil should be designed to map the actual risk of these potentially harmful side-effects.

Riociguat for pulmonary arterial hypertension and chronic thromboembolic pulmonary hypertension: Results from a phase II long-term extension study.

BACKGROUND: Riociguat was well tolerated and improved exercise and functional capacity in patients with pulmonary arterial hypertension (PAH) and inoperable chronic thromboembolic pulmonary hypertension (CTEPH) in a 12-week Phase II trial. We present final data from the long-term extension phase of this study. METHODS: During this multicenter, open-label, uncontrolled long-term extension study, riociguat dose could be changed at the physician's discretion (range 0.5-2.5 mg three times daily). The primary outcome was long-term safety and tolerability of riociguat; secondary outcomes included 6-minute walking distance, World Health Organization functional class, survival, and clinical worsening-free survival. RESULTS: Sixty-eight patients (inoperable CTEPH, n = 41; PAH, n = 27) entered the long-term extension. Median treatment duration at the final data cut-off was 77 months. The most common adverse events were nasopharyngitis (57%) and peripheral edema (37%). Three patients (4%) experienced serious adverse events of hemoptysis: two moderate, one severe, none fatal or considered drug-related. At Month 48, 6-minute walking distance increased from baseline by 69 ± 105 m, and World Health Organization functional class improved/stabilized/worsened versus baseline in 50/45/5% of patients. Three-year survival and clinical worsening-free survival were 91% and 49%, respectively (with patients censored if they withdrew without experiencing an event). Starting a new PAH treatment was the most frequent clinical worsening event. CONCLUSIONS: Improvements in exercise and functional capacity were maintained at 4 years in patients remaining on treatment, with no new safety signals identified. These data support riociguat as a long-term treatment option for PAH and inoperable CTEPH. TRIAL REGISTERED AT: ClinicalTrials.gov. REGISTRATION NUMBER: NCT00454558.

Discovery of liver-directed glucokinase activator having anti-hyperglycemic effect without hypoglycemia.

Glucokinase activators (GKAs) are among the emerging drug candidates for the treatment of type 2 diabetes (T2D). Despite effective blood glucose lowering in clinical trials, many pan-GKAs "acting both in pancreas and liver" have been discontinued from clinical development mainly because of their potential to cause hypoglycemia. Pan-GKAs over sensitize pancreatic GK, resulting in insulin secretion even at sub-normoglycemic level which might be a possible explanation for hypoglycemia. An alternative approach to minimize the risk of hypoglycemia is to use liver-directed GKAs, which are reported to be advancing well in clinical development. Here, we report the discovery and structure-activity relationship (SAR) studies on a novel 2-phenoxy-acetamide series with the aim of identifying a liver-directed GKA. Incorporation of a carboxylic acid moiety as an active hepatocyte uptake recognizing element at appropriate position of 2-phenoxy-acetamide core led to the identification of 26, a potent GKA with predominant liver-directed pharmacokinetics in mice. Compound 26 on oral administration significantly reduced blood glucose levels during an oral glucose tolerance test (oGTT) performed in diet-induced obese (DIO) mice, while showing no sign of hypoglycemia in normal C57 mice over a 10-fold dose range, even when dosed at fasted condition. Together, these data demonstrate a liver-directed GKA has beneficial effect on glucose homeostasis with reduced risk of hypoglycemia.

Glycemic Effect and Safety of a Systemic, Partial Glucokinase Activator, PF-04937319, in Patients With Type 2 Diabetes Mellitus Inadequately Controlled on Metformin-A Randomized, Crossover, Active-Controlled Study.

Glucokinase enhances glucose conversion to glucose-6-phosphate, causing glucose-stimulated insulin secretion from pancreatic ß cells and increased hepatic glucose uptake. PF-04937319 is a partial glucokinase activator designed to maintain efficacy with reduced hypoglycemia risk. In this randomized, double-blind, double-dummy, 3-period crossover phase 1b study, patients aged 18-70 years with type 2 diabetes mellitus and on metformin received once-daily PF-04937319 (300 mg), split-dose PF-04937319 (150+100 mg; breakfast+lunch), or sitagliptin (100 mg once daily). The primary end point was day 14 weighted mean daily glucose (WMDG) change from period-specific baseline. Secondary end points included change from baseline in fasting plasma glucose, premeal C-peptide and insulin, and safety, including hypoglycemia frequency. Mean decrease from baseline in observed WMDG (mg/dL) was greater for PF-04937319 (split-dose, -31.24; once daily, -31.33) versus sitagliptin (-19.24). Using the integrated glucose red-cell HbA1c model, the observed WMDG effect with both PF-04937319 dosing regimens was projected to yield a clinically superior effect on mean glycated hemoglobin (HbA1c ; split-dose, -0.88%; once daily, -0.94%) compared with sitagliptin (-0.63%). There was no difference in premeal C-peptide or insulin levels, and although the effect on WMDG with both PF-04937319 regimens was similar, the split-dose regimen appeared to offer some advantage in safety and tolerability.

Pharmacokinetic and Pharmacodynamic Drug Interaction Study of Piragliatin, a Glucokinase Activator, and Glyburide, a Sulfonylurea, in Type 2 Diabetic Patients.

A glucokinase activator and a sulfonylurea might be coprescribed to synergize treatment success for type 2 diabetes (T2D). This clinical pharmacology study was designed to investigate the potential glucose-lowering effect or pharmacodynamic (PD), pharmacokinetic (PK), and safety/tolerability interactions between piragliatin and glyburide in T2D patients already taking glyburide but not adequately controlled. This was an open-label, multiple-dose, 3-period, single-sequence crossover design: on days -1, 6, and 12, PD and PK samples were drawn with glyburide alone (period 0), piragliatin + glyburide (period 1), and piragliatin alone (period 2) treatments. The glucose-lowering effect, including fasting plasma glucose (FPG), of piragliatin was more pronounced when it was administered concomitantly with glyburide as compared to piragliatin or glyburide administered alone. However, this enhancement cannot be explained by a potential PK interaction between piragliatin and glyburide. Other than hypoglycemia, there were no clinically relevant safety findings. Thus, the enhanced PD effect warrants further investigation to define the optimal dose combination between glucokinase activators and sulfonylureas with regard to efficacy, safety, and tolerability.

Bryostatin-1 for latent virus reactivation in HIV-infected patients on antiretroviral therapy.

OBJECTIVE: The protein kinase C (PKC) agonist bryostatin-1 has shown significant ex-vivo potency to revert HIV-1 latency, compared with other latency reversing agents (LRA). The safety of this candidate LRA remains to be proven in treated HIV-1-infected patients. METHODS: In this pilot, double-blind phase I clinical-trial (NCT 02269605), we included aviraemic HIV-1-infected patients on triple antiretroviral therapy to evaluate the effects of two different single doses of bryostatin-1 (10 or 20 µg/m) compared with placebo. RESULTS: Twelve patients were included, four in each arm. Bryostatin-1 was well tolerated in all participants. Two patients in the 20 µg/m arm developed grade 1 headache and myalgia. No detectable increases of cell-associated unspliced (CA-US) HIV-1-RNA were observed in any study arm, nor differences in HIV-1 mRNA dynamics between arms (P = 0.44). The frequency of samples with low-level viraemia did not differ between arms and low-level viraemia did not correlate with CA-US HIV-1-RNA levels (P = 0.676). No changes were detected on protein kinase C (PKC) activity and in biomarkers of inflammation (sCD14 and interleukin-6) in any study arm. After the single dose of bryostatin-1, plasma concentrations were under detection limits in all the patients in the 10 µg/m arm, and below 50 pg/ml (0.05 nmol/l) in those in the 20 µg/m arm. CONCLUSION: Bryostatin-1 was safe at the single doses administered. However, the drug did not show any effect on PKC activity or on the transcription of latent HIV, probably due to low plasma concentrations. This study will inform next trials aimed at assessing higher doses, multiple dosing schedules or combination studies with synergistic drugs.

AMG 151 (ARRY-403), a novel glucokinase activator, decreases fasting and postprandial glycaemia in patients with type 2 diabetes.

Phase I studies have shown that AMG 151 activates glucokinase, a key enzyme in glucose homeostasis. The present randomized, placebo-controlled phase IIa study evaluated the dose-effect relationship of the glucokinase activator AMG 151 relative to placebo on fasting plasma glucose (FPG) in 236 patients (33-35 patients per arm) with type 2 diabetes treated with metformin. Patients received oral AMG 151 at 50, 100 or 200 mg twice daily, AMG 151 at 100, 200 or 400 mg once daily or matching placebo for 28 days. A significant linear dose-effect trend was observed with the twice-daily regimen (p = 0.004) for change in FPG to day 28. No trend was observed with the once-daily regimen. A higher incidence of hypoglycaemia and hypertriglyceridaemia was observed with AMG 151 administration. AMG 151 significantly reduced FPG when administered twice daily but not when administered once daily in patients with type 2 diabetes treated with metformin.

The design of covalent allosteric drugs.

A key issue in drug discovery is how to reduce drug dosage and increase specificity while retaining or increasing efficacy, as high dosage is often linked to toxicity. There are two types of drugs on the market: orthosteric and allosteric. Orthosteric drugs can be noncovalent or covalent. The latter are advantageous because they may be prescribed in lower doses, but their potential off-target toxicity is a primary concern. The chief advantages of allosteric drugs are their higher specificity and their consequently lower chance of toxic side effects. Covalent allosteric drugs combine the pharmacological merits of covalent drugs with the additional benefit of the higher specificity of allosteric drugs. In a recent promising step in therapeutic drug development, allosteric, disulfide-tethered fragments successfully modulated the activity of a protein kinase and K-Ras.

Impact of cytochrome P450 3A4 inducer and inhibitor on the pharmacokinetics of trabectedin in patients with advanced malignancies: open-label, multicenter studies.

PURPOSE: To evaluate the pharmacokinetics, safety and survival of trabectedin, metabolized primarily by cytochrome P450 (CYP)3A4 enzyme, when coadministered with rifampin (CYP3A4 inducer) or ketoconazole (CYP3A4 inhibitor) in adult patients with advanced solid tumors. METHODS: Two phase 1/2a, 2-way crossover studies were conducted. For rifampin study, 12 patients were randomized (1:1) to sequence of a cycle of trabectedin (1.3 mg/m(2), 3 h, i.v.) coadministered with rifampin (600 mg/day, 6-days), and a cycle of trabectedin monotherapy (1.3 mg/m(2), 3 h, i.v.). In ketoconazole study, eight patients were randomized (1:1) to sequence of a cycle of trabectedin (0.58 mg/m(2), 3 h, i.v.) coadministered with ketoconazole (200 mg, twice-daily, 15-doses), and a cycle of trabectedin monotherapy (1.3 mg/m(2), 3 h, i.v.). RESULTS: The systemic exposure (geometric means) of trabectedin was decreased [22% (C max) and 31% (AUClast)] with rifampin coadministration and increased [22% (C max) and 66% (AUClast)] with ketoconazole coadministration. This correlated with an increased clearance with rifampin (39.6-59.8 L/h) and a decreased clearance with ketoconazole (20.3-12.0 L/h). Consistent with earlier studies, the most common (≥40%) treatment-emergent adverse events in both studies were nausea, vomiting, diarrhea, hepatic function abnormal, anemia, neutropenia, thrombocytopenia and leukopenia. CONCLUSIONS: Coadministration of rifampin or ketoconazole altered the pharmacokinetics of trabectedin, but no new safety signals were observed. Coadministration of trabectedin with potent CYP3A4 inhibitors or inducers should be avoided if possible. If coadministration of trabectedin with a strong CYP3A4 inhibitor is required, close monitoring for toxicities is recommended, so that appropriate dose reductions can be instituted as warranted.