Safety and Pharmacokinetics of Quizartinib Combination Therapy With Standard Induction and Consolidation Chemotherapy in Patients With Newly Diagnosed Acute Myeloid Leukemia: Results from Two Phase 1 Trials in Japan and China

Quizartinib is a potent, oral, second-generation, selective type II FMS-like receptor tyrosine kinase 3 (FLT3) inhibitor. It has shown improved overall survival in a randomized, multinational, Phase 3 (QuANTUM-First) study in patients with FLT3-internal tandem duplication (ITD)-positive newly diagnosed acute myeloid leukemia. We conducted 2 Phase 1b studies in Japan and China to evaluate the safety, pharmacokinetics, and efficacy of quizartinib in combination with standard induction and consolidation chemotherapy in patients with newly diagnosed acute myeloid leukemia. Quizartinib was started at a dose level of 20 mg/day and then escalated to 40 mg/day, the dose used in the Phase 3 study. Seven patients were enrolled according to the 3 + 3 dose-escalation method in each study, including 3 patients who were FLT3-ITD positive. No dose-limiting toxicities were observed at dose levels up to 40 mg/day in both studies. Grade 3 or higher, quizartinib-related, treatment-emergent adverse events included febrile neutropenia, hematologic toxicities, and infections. QT prolongation on electrocardiogram was observed in 5 patients. The pharmacokinetics of quizartinib and its metabolite AC886 were similar between the studies and consistent with previous findings in the United States. We confirmed the tolerability of Japanese and Chinese patients to the dose of quizartinib and chemotherapy regimens used in the QuANTUM-First study.

A Randomized, Controlled Trial of the Pan-PPAR Agonist Lanifibranor in NASH

BACKGROUND

Management of nonalcoholic steatohepatitis (NASH) is an unmet clinical need. Lanifibranor is a pan-PPAR (peroxisome proliferator-activated receptor) agonist that modulates key metabolic, inflammatory, and fibrogenic pathways in the pathogenesis of NASH.

METHODS

In this phase 2b, double-blind, randomized, placebo-controlled trial, patients with noncirrhotic, highly active NASH were randomly assigned in a 1:1:1 ratio to receive 1200 mg or 800 mg of lanifibranor or placebo once daily for 24 weeks. The primary end point was a decrease of at least 2 points in the SAF-A score (the activity part of the Steatosis, Activity, Fibrosis [SAF] scoring system that incorporates scores for ballooning and inflammation) without worsening of fibrosis; SAF-A scores range from 0 to 4, with higher scores indicating more-severe disease activity. Secondary end points included resolution of NASH and regression of fibrosis.

RESULTS

A total of 247 patients underwent randomization, of whom 103 (42%) had type 2 diabetes mellitus and 188 (76%) had significant (moderate) or advanced fibrosis. The percentage of patients who had a decrease of at least 2 points in the SAF-A score without worsening of fibrosis was significantly higher among those who received the 1200-mg dose, but not among those who received the 800-mg dose, of lanifibranor than among those who received placebo (1200-mg dose vs. placebo, 55% vs. 33%, P = 0.007; 800-mg dose vs. placebo, 48% vs. 33%, P = 0.07). The results favored both the 1200-mg and 800-mg doses of lanifibranor over placebo for resolution of NASH without worsening of fibrosis (49% and 39%, respectively, vs. 22%), improvement in fibrosis stage of at least 1 without worsening of NASH (48% and 34%, respectively, vs. 29%), and resolution of NASH plus improvement in fibrosis stage of at least 1 (35% and 25%, respectively, vs. 9%). Liver enzyme levels decreased and the levels of the majority of lipid, inflammatory, and fibrosis biomarkers improved in the lanifibranor groups. The dropout rate for adverse events was less than 5% and was similar across the trial groups. Diarrhea, nausea, peripheral edema, anemia, and weight gain occurred more frequently with lanifibranor than with placebo.

CONCLUSIONS

In this phase 2b trial involving patients with active NASH, the percentage of patients who had a decrease of at least 2 points in the SAF-A score without worsening of fibrosis was significantly higher with the 1200-mg dose of lanifibranor than with placebo. These findings support further assessment of lanifibranor in phase 3 trials. (Funded by Inventiva Pharma; NATIVE ClinicalTrials.gov number, NCT03008070.).

Prolongation of metallothionein induction combats Aß and α-synuclein toxicity in aged transgenic Caenorhabditis elegans

Neurodegenerative disorders (ND) like Alzheimer's (AD), Parkinson's (PD), Huntington's or Prion diseases share similar pathological features. They are all age dependent and are often associated with disruptions in analogous metabolic processes such as protein aggregation and oxidative stress, both of which involve metal ions like copper, manganese and iron. Bush and Tanzi proposed 2008 in the 'metal hypothesis of Alzheimer's disease' that a breakdown in metal homeostasis is the main cause of NDs, and drugs restoring metal homeostasis are promising novel therapeutic strategies. We report here that metallothionein (MT), an endogenous metal detoxifying protein, is increased in young amyloid ß (Aß) expressing Caenorhabditis elegans, whereas it is not in wild type strains. Further MT induction collapsed in 8 days old transgenic worms, indicating the age dependency of disease outbreak, and sharing intriguing parallels to diminished MT levels in human brains of AD. A medium throughput screening assay method was established to search for compounds increasing the MT level. Compounds known to induce MT release like progesterone, ZnSO4, quercetin, dexamethasone and apomorphine were active in models of AD and PD. Thioflavin T, clioquinol and emodin are promising leads in AD and PD research, whose mode of action has not been fully established yet. In this study, we could show that the reduction of Aß and α-synuclein toxicity in transgenic C. elegans models correlated with the prolongation of MT induction time and that knockdown of MT with RNA interference resulted in a loss of bioactivity.

New Treatments in Renal Cancer: The AhR Ligands

Kidney cancer rapidly acquires resistance to antiangiogenic agents, such as sunitinib, developing an aggressive migratory phenotype (facilitated by c-Metsignal transduction). The Aryl hydrocarbon receptor (AhR) has recently been postulated as a molecular target for cancer treatment. Currently, there are two antitumor agent AhR ligands, with activity against renal cancer, that have been tested clinically: aminoflavone (AFP 464, NSC710464) and the benzothiazole (5F 203) prodrug Phortress. Our studies investigated the action of AFP 464, the aminoflavone pro-drug currently used in clinical trials, and 5F 203 on renal cancer cells, specifically examining their effects on cell cycle progression, apoptosis and cell migration. Both compounds caused cell cycle arrest and apoptosis but only 5F 203 potently inhibited the migration of TK-10, Caki-1 and SN12C cells as well as the migration signal transduction cascade, involving c-Met signaling, in TK-10 cells. Current investigations are focused on the development of nano-delivery vehicles, apoferritin-encapsulated benzothiazoles 5F 203 and GW610, for the treatment of renal cancer. These compounds have shown improved antitumor effects against TK-10 cells in vitro at lower concentrations compared with a naked agent.

The effect for hyperuricemia inpatient of uric acid overproduction type or in combination with topiroxostat on the pharmacokinetics, pharmacodynamics and safety of dotinurad, a selective urate reabsorption inhibitor

BACKGROUND

Dotinurad, a novel selective urate reabsorption inhibitor (SURI), increases urinary uric acid excretion. The aim of this study is to examine the pharmacokinetics, pharmacodynamics, and safety of dotinurad according to the type of hyperuricemia, with or without concomitant use of xanthine oxidase inhibitor, in uric acid "overproduction type" patients.

METHODS

This open-label clinical pharmacology study was conducted in a hospital. Dotinurad 1 mg was administered for 7 days to hyperuricemic patients with uric acid "overproduction type" (overproduction group, n = 6; and combination group, n = 6) and uric acid "underexcretion type" (underexcretion group, n = 6). In the combination group, topiroxostat 80 mg was used concomitantly.

RESULTS

No significant differences were observed in pharmacokinetics and safety between overproduction group and underexcretion group, and the percent change in serum uric acid level and the amount of urinary uric acid excretion after administration were comparable. In "overproduction type" patients of combination group, the percent change in serum uric acid level significantly increased and the amount of urinary uric acid excretion significantly decreased compared to those of overproduction group. No clinically meaningful differences were observed in safety between the overproduction group and the combination group.

CONCLUSION

In inpatients, differences in hyperuricemic type did not significantly influence the pharmacokinetics, pharmacodynamics, and safety of dotinurad. Moreover, in "overproduction type", the coadministration of dotinurad and topiroxostat had an add-on serum uric acid lowering effect and suppressed urinary uric acid excretion.

TRIAL REGISTRATION

ClinicalTrials.gov Identifier: NCT02837198.

A drug-drug interaction study of a novel, selective urate reabsorption inhibitor dotinurad and the non-steroidal anti-inflammatory drug oxaprozin in healthy adult males

Background

Dotinurad is a novel, selective urate reabsorption inhibitor, which reduces serum uric acid levels by inhibiting the urate transporter 1. The results of nonclinical studies indicated the possibility that the concomitant use of the non-steroidal anti-inflammatory drug oxaprozin affects the pharmacokinetics of dotinurad. We evaluated drug–drug interactions with respect to the pharmacokinetics and safety of dotinurad when co-administered with oxaprozin.

Methods

This was an open-label, two-period, add-on study in healthy adult males. For a single dose of 4 mg of dotinurad with and without oxaprozin, we compared its pharmacokinetic parameters and evaluated safety.

Results

This study enrolled 12 subjects, 11 of whom completed the study. The geometric mean ratio (90% confidence interval [CI]) of the urinary excretion rate of glucuronate conjugates of dotinurad after co-administration with oxaprozin compared to administration of dotinurad alone was 0.657 (0.624–0.692), while the geometric mean ratios (90% CIs) of the maximum plasma concentration and area under the plasma concentration–time curve from time zero to infinity (AUC_0–inf) were 0.982 (0.945–1.021) and 1.165 (1.114–1.219), respectively. During the study, two adverse events occurred after administration of dotinurad alone and one occurred after administration of oxaprozin alone.

Conclusions

In comparison with administration of dotinurad alone, co-administration with oxaprozin was associated with a 34.3% decrease in the urinary excretion rate of the glucuronate conjugates of dotinurad, and a 16.5% increase in AUC_0–inf of dotinurad. However, no clinically meaningful drug–drug interactions were observed. Administration of dotinurad alone was similar safety to co-administration with oxaprozin.

Clinical trial registration

ClinicalTrials.gov Identifier: NCT03350386.

Dotinurad versus benzbromarone in Japanese hyperuricemic patient with or without gout: a randomized, double-blind, parallel-group, phase 3 study

Background

Dotinurad is a novel selective urate reabsorption inhibitor that reduces serum urate levels in hyperuricemic patients with or without gout by selectively inhibiting urate transporter 1. This study was conducted to compare the efficacy and safety of dotinurad with those of benzbromarone.

Methods

In this 14-week, randomized, multicenter, double-blind, parallel-group, dose escalation, benzbromarone-controlled, phase 3 study, hyperuricemic patients with or without gout were randomized to two groups that received either dotinurad 2 mg or benzbromarone 50 mg. Dotinurad or benzbromarone was administered once a day for 14 weeks. The primary endpoint was the percent change in serum uric acid level from the baseline to the final visit.

Results

A total of 201 Japanese hyperuricemic patients with or without gout (dotinurad: 102, benzbromarone: 99) received at least one dose of the study drug. The mean percent change in serum uric acid level from the baseline to the final visit in the dotinurad and benzbromarone groups was 45.9% and 43.8%, respectively. Non-inferiority of dotinurad 2 mg to benzbromarone 50 mg in lowering serum uric acid was verified by the predefined non-inferiority margin (95% CI − 1.27 to 5.37%). The incidence of adverse events and adverse drug reactions was comparable between the two groups.

Conclusion

Dotinurad 2 mg was verified to have a non-inferior serum uric acid lowering effect compared with benzbromarone 50 mg, in Japanese hyperuricemic patients with or without gout.

ClinicalTrials.gov Identifier

NCT03100318.

A non-inferiority study of the novel selective urate reabsorption inhibitor dotinurad versus febuxostat in hyperuricemic patients with or without gout

Background

Dotinurad is a novel, selective urate reabsorption inhibitor, which reduces serum uric acid levels by selective inhibition of the urate transporter 1. We evaluated the efficacy and safety of dotinurad versus febuxostat, a widely used drug in Japan, in hyperuricemic Japanese patients with or without gout.

Methods

This was a multicenter, randomized, double-blind, active-controlled, parallel-group, forced-titration study in hyperuricemic patients. Study treatment in the dotinurad and febuxostat groups was initiated at 0.5 and 10 mg/day, followed by dose titration to 2 and 40 mg/day, respectively, over 14 weeks. The primary endpoint was the percent change in serum uric acid level from the baseline to the final visit.

Results

A total of 203 hyperuricemic patients with or without gout were enrolled in the study and randomized to receive dotinurad or febuxostat. The percent change in serum uric acid level from the baseline to the final visit was 41.82% in the dotinurad group and 44.00% in the febuxostat group. The mean difference was − 2.17% (two-sided 95% confidence interval − 5.26% to 0.92%). The lower limit of the interval was above the non-inferiority margin (− 10%), demonstrating the non-inferiority of dotinurad to febuxostat. The profiles of adverse events and adverse drug reactions raised no noteworthy safety concerns in either group.

Conclusion

The non-inferiority of dotinurad to febuxostat in terms of serum uric acid lowering effect was confirmed. No noteworthy safety concerns arose.

Patch Testing with a New Composition of Mercapto Mix: A Multi-centre Study by the Swedish Contact Dermatitis Research Group

This study investigated whether more patients with contact allergies were detected by patch testing with mercapto mix with a higher concentration of 2-mercaptobenzothiazolinone (MBT) than the commonly used mercapto mix. A total of 3,143 dermatitis patients in 5 Swedish dermatology departments were patch- tested with 3 mercapto test preparations: MBT 2.0% petrolatum (pet.); mercapto mix 2.0% pet.; and mercapto mix 3.5% pet. Positive reactions to these mercapto mixes varied between 0-0.50%, 0-0.93%, and 0-1.4%, respectively, in the 5 centres. Numerically, mercapto mix 3.5% pet. detected all positive patients and more patch-test positive patients than did the 2 other substances, but the difference was not statistically significant. The authors recommend replacing mercapto mix 2.0% pet. in the Swedish baseline series with mercapto mix 3.5% pet., since the latter also detected those patients who would have been missed because MBT 2.0% is not included in the Swedish baseline series.

A drug-drug interaction study to assess the potential effect of acid-reducing agent, lansoprazole, on quizartinib pharmacokinetics

PURPOSE

Quizartinib, a potent, selective FMS-like tyrosine kinase 3 (FLT3) inhibitor, is currently in phase 3 development for patients with FLT3-internal tandem duplication-mutated acute myeloid leukemia (AML). Acid-reducing agents (ARAs; e.g., proton pump inhibitors) are frequently used during AML treatment. Since quizartinib demonstrates pH-dependent solubility, the effect of lansoprazole coadministration on pharmacokinetics (PK) of quizartinib tablet formulation was assessed.

METHODS

An open-label, parallel-group study randomized 64 healthy adults to single-dose quizartinib 30 mg alone (reference) or lansoprazole (60 mg once daily, days 1-5) + single-dose quizartinib 30 mg (day 5) (test). Plasma concentrations of quizartinib and its active metabolite, AC886, were measured to 504 h postdose; the effect of lansoprazole on quizartinib PK was assessed by analysis of variance.

RESULTS

Quizartinib geometric mean ratios (test/reference) and 90% confidence intervals for maximum observed plasma concentration (Cmax), area under the concentration-time curve to last measurable drug concentration (AUClast), and AUC to infinity were 86.11% (78.4%, 94.6%), 93.96% (79.6%, 110.9%), and 95.30% (80.2%, 113.3%), respectively. Comparisons showed a modest decrease in quizartinib absorption when co-administered with lansoprazole, with lower limits for Cmax and AUClast just below 80-125% limits. Treatment-emergent adverse events were mild or moderate; the most frequent in either treatment group were headache [quizartinib alone: (n = 3) 10%], upper respiratory tract infection [quizartinib alone: (n = 2) 6.7%; lansoprazole + quizartinib: (n = 3) 9.1%], and muscle tightness [quizartinib alone: (n = 2) 6.7%].

CONCLUSIONS

Concomitant lansoprazole had minimal effect on quizartinib PK as a formulated tablet, indicating that quizartinib can be administered with ARAs.

Amyloid-β PET-Correlation with cerebrospinal fluid biomarkers and prediction of Alzheimer´s disease diagnosis in a memory clinic

Background

Alzheimer’s disease (AD) remains a clinical diagnosis but biomarkers from cerebrospinal fluid (CSF) and more lately amyloid imaging with positron emission tomography (PET), are important to support a diagnosis of AD.

Objective

To compare amyloid-β (Aβ) PET imaging with biomarkers in CSF and evaluate the prediction of Aβ PET on diagnosis in a memory clinic setting.

Methods

We included 64 patients who had lumbar puncture and Aβ PET with ¹⁸F-Flutemetamol performed within 190 days. PET was binary classified (Flut+ or Flut-) and logistic regression analyses for correlation to each CSF biomarker; Aβ 42 (Aβ₄₂), total tau (T-tau) and phosphorylated tau (P-tau), were performed. Cut-off values were assessed by receiver operating characteristic (ROC) curves. Logistic regression was performed for prediction of clinical AD diagnosis. We assessed the interrater agreement of PET classification as well as for diagnoses, which were made both with and without knowledge of PET results.

Results

Thirty-two of the 34 patients (94%) in the Flut+ group and nine of the 30 patients (30%) in the Flut- group had a clinical AD diagnosis. There were significant differences in all CSF biomarkers in the Flut+ and Flut- groups. Aβ₄₂ showed the highest correlation with ¹⁸F-Flutemetamol PET with a cut-off value of 706.5 pg/mL, corresponding to sensitivity of 88% and specificity of 87%. ¹⁸F-Flutemetamol PET was the best predictor of a clinical AD diagnosis. We found a very high interrater agreement for both PET classification and diagnosis.

Conclusions

The present study showed an excellent correlation of Aβ₄₂ in CSF and ¹⁸F-Flutemetamol PET and the presented cut-off value for Aβ₄₂ yields high sensitivity and specificity for ¹⁸F-Flutemetamol PET. ¹⁸F-Flutemetamol PET was the best predictor of clinical AD diagnosis.

Syntheses of Benzo[d]Thiazol-2(3H)-One Derivatives and Their Antidepressant and Anticonvulsant Effects

Thirty-four new benzo[d]thiazol derivatives 2a–2i, 3a–3r, and 4a–4g were synthesized and investigated for their potential antidepressant and anticonvulsant effects. In a forced swimming test, 2c and 2d showed the highest antidepressant and anticonvulsant effects. 2c and 2d displayed a higher percentage decrease in immobility duration (89.96% and 89.62%, respectively) than that of fluoxetine (83.62%). In the maximal electroshock seizure test, 3n and 3q showed the highest anticonvulsant effect, with ED₅₀ values of 46.1 and 64.3 mg kg⁻¹, and protective indices of 6.34 and 4.11, respectively, which were similar to those of phenobarbital or valproate. We also found that the mechanism for the antidepressant activity of 2c and 2d may be via increasing the concentrations of serotonin and norepinephrine.

[Increased frequency and spread of restlessness as the early manifestation of Parkinson's disease in a woman with restless legs syndrome]

A 57-year-old woman had been suffered from insomnia due to restlessness and abnormal sensation of the left side of the body for 33 years. Since the preceding year of the first visit frequency of the symptoms increased, and the abnormal sensation was spread to the right leg. Her daughter had restless legs syndrome (RLS) since age 20. Neurological examination showed no abnormality. Laboratory test results showed normal ferritin levels. There was no renal dysfunction or anemia. A diagnosis of RLS was made, and her symptoms responded well to pramipexole treatment. However, the patient developed right shoulder pain and right-hand tremor one year and one and a half year after the first visit, respectively. Based on clinical findings and the findings of dopamine transporter scan and cardiac ¹²³I-MIBG scintigraphy, the patient was diagnosed with Parkinson's disease (PD). Careful observation of changes in RLS symptoms is required as an increased frequency and spread of symptoms of RLS could be the early manifestation of PD.

Assessment of sigma-1 receptor occupancy in mice with non-radiolabelled FTC-146 as a tracer

The use of liquid chromatography coupled with mass spectrometry (LC-MS/MS) is advantageous in in-vivo receptor occupancy assays at pre-clinical drug developmental stages. Relatively, its application is effective in terms of high throughput, data reproducibility, sensitivity, and sample processing. In this perspective, we have evaluated the use of FTC-146 as a non-radiolabelled tracer to determine the sigma-1 receptor occupancy of test drugs in mice brain. Further, the brain and plasma exposures of test drug were determined at their corresponding occupancies. In this occupancy method, the optimized tracer treatment (sacrification) time after intravenous administration was 30 min. The tracer dose was 3 µg/kg and specific brain regions of interest were frontal cortex, pons and midbrain. Mice were pretreated orally with SA4503, fluspidine, haloperidol, and donepezil followed by tracer treatment. Among the test drugs, SA4503 was used as positive control group at its highest test dose (7 mg/kg, intraperitoneal). There was a dose-dependent decrease in brain regional FTC-146 binding in pretreated mice. From the occupancy curves of SA4503, fluspidine, haloperidol, and donepezil the effective dose (ED50) value ranges are 0.74-1.45, 0.09-0.11, 0.11-0.12, and 0.07-0.09 mg/kg, respectively. Their corresponding brain effective concentration (EC50) values are 74.3-132.5, 3.4-3.7, 122.5-139.5, and 8.8-11.0 ng/g and plasma EC50 values are 34.3-53.7, 0.08-0.10, 7.8-9.5, and 0.6-0.7 ng/mL. Brain regional distribution and binding inhibition upon pretreatment were comparable with data reported with labeled [18F]FTC-146. Drug exposures were simultaneously determined and correlated with sigma-1 occupancy from the same experiment. Wide category drugs can be assayed for sigma-1 receptor engagement and their correlation with exposures aid in clinical development.

Intravenous Administration-Oriented Pharmacokinetic Model for Dynamic Bioluminescence Imaging

OBJECTIVE

In vivo bioluminescence imaging (BLI) is a promising tool for monitoring the growth and metastasis of tumors. However, quantitative BLI research based on intravenous (IV) injection is limited, which greatly restricts its further application. To address this problem, we designed a pharmacokinetic (PK) model which is suitable for applying on IV administration of small amounts of D-Luciferin.

METHODS

After three weeks of postimplantation, mkn28-luc xenografted mice were subjected to 40-min dynamic BLI immediately following D-Luciferin intravenous injection on days 1, 3, 5, 7, and 9. Furthermore, the PK model was applied on dynamic BLI data to obtain the sum of kinetic rate constants (SKRC).

RESULTS

Results showed that the SKRC values decreased rapidly with the growth of the tumor. There was a statistical difference between the SKRC values measured at different time points, while the time point of luminous intensity peak was unaffected by the growth of the tumor.

CONCLUSION

In short, our results imply that dynamic BLI combined with our PK model can predict tumor growth earlier and with higher sensitivity compared to the conventional method, which is crucial for improving drug evaluation efficacy. In addition, the dynamic BLI may provide a valuable reference for the noninvasive acquiring arterial input function, which may also provide a new application prospect for hybrid PET-optical imaging.

Results of a phase 1 study of quizartinib as maintenance therapy in subjects with acute myeloid leukemia in remission following allogeneic hematopoietic stem cell transplant

FLT3-ITD-mutated acute myeloid leukemia (AML) has very high risk of relapse and is associated with poor outcome following allogeneic hematopoietic-cell transplant (allo-HCT). This two-part, phase 1, multicenter, open-label, sequential-group, dose-escalation study aimed to determine dose-limiting toxicities (DLTs), maximum tolerated dose (MTD), and safety/tolerability of quizartinib, a selective and highly potent FLT3 inhibitor, when administered as maintenance therapy after allo-HCT. Thirteen subjects with documented FLT3-ITD-mutated AML in morphological remission following allo-HCT received one of two quizartinib dihydrochloride dose levels (DL): 40 mg/d (DL1; n = 7) and 60 mg/d (DL2; n = 6), administered orally in 28-day cycles for up to 24 cycles. Median age of participants was 43 years. All subjects received human leukocyte antigen (HLA)-matched allo-HCT. One subject treated at DL1 and 1 treated at DL2 had DLTs that required drug interruption (grade 3 gastric hemorrhage and grade 3 anemia, respectively). Ten subjects (77%) received quizartinib for >1 year; 5 (38%) completed 24 cycles. Four subjects (31%) discontinued quizartinib due to adverse events. One subject (8%) experienced relapse during cycle 1 and discontinued treatment. Most common grade 3/4 adverse events were neutropenia (23%), anemia (15%), leukopenia (15%), lymphopenia (15%), and thrombocytopenia (15%). This study demonstrated acceptable tolerability and early evidence of reduced relapse rate following allo-HCT with quizartinib maintenance compared to historical cohorts. No MTD was identified, but 60 mg daily was selected as highest dose for continuous daily administration based on randomized comparison of daily 30 and 60 mg doses in relapsed/refractory AML.

Nucleolin and ErbB2 inhibition reduces tumorigenicity of ErbB2-positive breast cancer

ErbB2, a member of the ErbB family of receptor tyrosine kinases, is an essential player in the cell's growth and proliferation signaling pathways. Amplification or overexpression of ErbB2 is observed in ∼30% of breast cancer patients, and often drives cellular transformation and cancer development. Recently, we have shown that ErbB2 interacts with the nuclear-cytoplasmic shuttling protein nucleolin, an interaction which enhances cell transformation in vitro, and increases mortality risk and disease progression rate in human breast cancer patients. Given these results, and since acquired resistance to anti-ErbB2-targeted therapy is a major obstacle in treatment of breast cancer, we have examined the therapeutic potential of targeting the ErbB2-nucleolin complex. The effect of the nucleolin-specific inhibitor GroA (AS1411) on ErbB2-positive breast cancer was tested in vivo, in a mouse xenograft model for breast cancer; as well as in vitro, alone and in combination with the ErbB2 kinase-inhibitor tyrphostin AG-825. Here, we show that in vivo treatment of ErbB2-positive breast tumor xenografts with GroA reduces tumor size and leads to decreased ErbB2-mediated signaling. Moreover, we found that co-treatment of breast cancer cell lines with GroA and the ErbB2 kinase-inhibitor tyrphostin AG-825 enhances the anti-cancer effects exerted by GroA alone in terms of cell viability, mortality, migration, and invasiveness. We, therefore, suggest a novel therapeutic approach, consisting of combined inhibition of ErbB2 and nucleolin, which has the potential to improve breast cancer treatment efficacy.

Co-delivery of cisplatin and CJM-126 via photothermal conversion nanoparticles for enhanced synergistic antitumor efficacy

Polymeric biomaterials that can be smartly disassembled through the cleavage of the covalent bonds in a controllable way upon an environmental stimulus such as pH change, redox, special enzymes, temperature, or ultrasound, as well as light irradiation, but are otherwise stable under normal physiological conditions have attracted great attention in recent decades. The 2-(4-aminophenyl) benzothiazole molecule (CJM-126), as one of the benzothiazole derivatives, has exhibited a synergistic effect with cisplatin (CDDP) and restrains the bioactivities of a series of human breast cancer cell lines. In our study, novel NIR-responsive targeted binary-drug-loaded nanoparticles encapsulating indocyanine green (ICG) dye were prepared as a new co-delivery and combined therapeutic vehicle. The prepared drug-loaded polymeric nanoparticles (TNPs/CDDP-ICG) are stable under normal physiological conditions, while burst drugs release upon NIR laser irradiation in a mild acidic environment. The results further confirmed that the designed co-delivery platform showed higher cytotoxicity than the single free CDDP due to the synergistic treatment of CJM-126 and CDDP in vitro. Taken together, the work might provide a promising approach for effective site-specific antitumor therapy.

[A 70-year-old woman presenting with restless shoulder following posterior internal capsule infarction]

A 70-year-old woman noticed difficulty in speech and weakness of the left upper and lower limb upon awakening. Neurological examination showed dysarthria and left hemiparesis. No sensory disturbance was observed. Brain MRI revealed acute infarction in the right posterior limb of the internal capsule. On the hospital day 1, she developed the abnormal sensations restricted to the bilateral shoulders, resulting in difficulty initiating sleep. On laboratory data, renal function and serum hemoglobin and ferritin levels were normal. When four essential features of restless legs syndrome (RLS) were applied to her shoulders, the patient met RLS criteria. Following low dose pramipexole treatment, the abnormal sensation of the shoulders and insomnia significantly improved. We should be aware of the possibility of RLS or its variant, including "restless shoulder" of our patient, for the cause of insomnia following acute ischemic infarction.

Targeting RNA-Polymerase I in Both Chemosensitive and Chemoresistant Populations in Epithelial Ovarian Cancer

Purpose: A hallmark of neoplasia is increased ribosome biogenesis, and targeting this process with RNA polymerase I (Pol I) inhibitors has shown some efficacy. We examined the contribution and potential targeting of ribosomal machinery in chemotherapy-resistant and -sensitive models of ovarian cancer.Experimental Design: Pol I machinery expression was examined, and subsequently targeted with the Pol I inhibitor CX-5461, in ovarian cancer cell lines, an immortalized surface epithelial line, and patient-derived xenograft (PDX) models with and without chemotherapy. Effects on viability, Pol I occupancy of rDNA, ribosomal content, and chemosensitivity were examined.Results: In PDX models, ribosomal machinery components were increased in chemotherapy-treated tumors compared with controls. Thirteen cell lines were sensitive to CX-5461, with IC₅₀s 25 nmol/L-2 μmol/L. Interestingly, two chemoresistant lines were 10.5- and 5.5-fold more sensitive than parental lines. CX-5461 induced DNA damage checkpoint activation and G₂-M arrest with increased γH2AX staining. Chemoresistant cells had 2- to 4-fold increased rDNA Pol I occupancy and increased rRNA synthesis, despite having slower proliferation rates, whereas ribosome abundance and translational efficiency were not impaired. In five PDX models treated with CX-5461, one showed a complete response, one a 55% reduction in tumor volume, and one maintained stable disease for 45 days.Conclusions: Pol I inhibition with CX-5461 shows high activity in ovarian cancer cell lines and PDX models, with an enhanced effect on chemoresistant cells. Effects occur independent of proliferation rates or dormancy. This represents a novel therapeutic approach that may have preferential activity in chemoresistant populations. Clin Cancer Res; 23(21); 6529-40. ©2017 AACR.

Quantification of highly selective sigma-1 receptor antagonist CM304 using liquid chromatography tandem mass spectrometry and its application to a pre-clinical pharmacokinetic study

An ultra-performance liquid chromatography-tandem mass spectrometry (UPLC-MS/MS) method was developed and validated for quantification of CM304, a novel and highly selective sigma-1 receptor antagonist that has recently entered into human clinical trials. A structural analogue of CM304, SN56, was used as the internal standard (IS). Chromatographic separation was achieved on an Acquity UPLC™ BEH C18 (1.7 μm, 2.1 mm × 50 mm) column using a mobile phase [water:methanol (0.1%v/v formic acid; 50:50, %v/v)] at a flow rate of 0.2 mL/min. Mass spectrometric detection was performed in the positive ionization mode with multiple reaction monitoring (MRM) using m/z transitions of 337 > 238 for CM304 and 319 > 220 for the IS. The method was found to be linear and reproducible with a regression coefficient consistently >0.99 for the calibration range of 3 to 3000 ng/mL. The extraction recovery ranged from 91.5 to 98.4% from spiked (7.5, 300 and 2526 ng/mL) plasma quality control samples. The precision (%RSD; 1.1 to 2.9%) and accuracy (%RE; -1.9 to 1.8%) were within acceptable limit. The validated method was successfully applied to a single dose oral and intravenous (I.V.) pharmacokinetic study of CM304 in rats. Following I.V. administration, the compound exhibited adequate exposure along with high extravascular distribution and insignificant amount of extra hepatic metabolism. Copyright © 2016 John Wiley & Sons, Ltd.

Electroencephalographic, cognitive, and neurochemical effects of LY3130481 (CERC-611), a selective antagonist of TARP-γ8-associated AMPA receptors

6-[(1S)-1-[1-[5-(2-hydroxyethoxy)-2-pyridyl]pyrazol-3-yl]ethyl]-3H-1,3-benzothiazol-2-one (LY3130481 or CERC-611) is a selective antagonist of AMPA receptors containing transmembrane AMPA receptor regulatory protein (TARP) γ-8. This molecule has been characterized as a potent and efficacious anticonvulsant in an array of acute and chronic epilepsy models in rodents. The present set of experiments was designed to assess the effects of LY3130481 on the electroencephelogram (EEG), cognitive function, and neurochemical outflow. LY3130481 disrupted food-maintained responding in rats and spontaneous alternation in a Y-maze in mice. In rat fear conditioning, LY3130481 caused a deficit in trace (hippocampal-dependent), but not in delay fear conditioning. Although these effects on cognitive performances were observed, the known cognitive-impairing anticonvulsant, topiramate, did not always produce deficits under these assay conditions. LY3130481 produced modest increases in wake times in rats. In addition, LY3130481 was able to attenuate some impairing effects of standard antiepileptic drugs. The motor-impairing effects of the lacosamide were attenuated by LY3130481 as was the decrease in non-rapid-eye movement sleep induced by carbamazepine. Evaluation of the effect of LY3130481 on neurotransmitter and metabolite efflux in the rat medial prefrontal cortex, using in vivo microdialysis, revealed significant increases in the pro-cognitive and wake-promoting neurotransmitters, histamine and acetylcholine, as well as in serotonin, telemethylhistamine, 5-HIAA, HVA and MHPG. LY3130481 thus presents a novel behavioral profile that will have to be evaluated in patients to fully appreciate its implications for therapeutics. LY3130481 is currently under clinical development as CERC-611 as an antiepileptic.

Visualizing Nerve Injury in a Neuropathic Pain Model with [18F]FTC-146 PET/MRI

The ability to locate nerve injury and ensuing neuroinflammation would have tremendous clinical value for improving both the diagnosis and subsequent management of patients suffering from pain, weakness, and other neurologic phenomena associated with peripheral nerve injury. Although several non-invasive techniques exist for assessing the clinical manifestations and morphological aspects of nerve injury, they often fail to provide accurate diagnoses due to limited specificity and/or sensitivity. Herein, we describe a new imaging strategy for visualizing a molecular biomarker of nerve injury/neuroinflammation, i.e., the sigma-1 receptor (S1R), in a rat model of nerve injury and neuropathic pain. The two-fold higher increase of S1Rs was shown in the injured compared to the uninjured nerve by Western blotting analyses. With our novel S1R-selective radioligand, [18F]FTC-146 (6-(3-[18F]fluoropropyl)-3-(2-(azepan-1-yl)ethyl)benzo[d]thiazol-2(3H)-one), and positron emission tomography-magnetic resonance imaging (PET/MRI), we could accurately locate the site of nerve injury created in the rat model. We verified the accuracy of this technique by ex vivo autoradiography and immunostaining, which demonstrated a strong correlation between accumulation of [18F]FTC-146 and S1R staining. Finally, pain relief could also be achieved by blocking S1Rs in the neuroma with local administration of non-radioactive [19F]FTC-146. In summary, [18F]FTC-146 S1R PET/MR imaging has the potential to impact how we diagnose, manage and treat patients with nerve injury, and thus warrants further investigation.

Spatial Targeting of Tumor-Associated Macrophages and Tumor Cells with a pH-Sensitive Cluster Nanocarrier for Cancer Chemoimmunotherapy

Chemoimmunotherapy, which combines chemotherapeutics with immune-modulating agents, represents an appealing approach for improving cancer therapy. To optimize its therapeutic efficacy, differentially delivering multiple therapeutic drugs to target cells is desirable. Here we developed an immunostimulatory nanocarrier (denoted as ^BLZ-945SCNs/Pt) that could spatially target tumor-associated macrophages (TAMs) and tumor cells for cancer chemoimmunotherapy. ^BLZ-945SCNs/Pt undergo supersensitive structure collapse in the prevascular regions of tumor tissues and enable the simultaneous release of platinum (Pt)-prodrug conjugated small particles and BLZ-945, a small molecule inhibitor of colony stimulating factor 1 receptor (CSF-1R) of TAMs. The released BLZ-945 can be preferentially taken up by TAMs to cause TAMs depletion from tumor tissues, while the small particles carrying Pt-prodrug enable deep tumor penetration as well as intracellularly specific drug release to kill more cancer cells. Our studies demonstrate that ^BLZ-945SCNs/Pt outperform their monotherapy counterparts in multiple tumor models. The underlying mechanism studies suggest that the designer pH-sensitive codelivery nanocarrier not only induces apoptosis of tumor cells but also modulates the tumor immune environment to eventually augment the antitumor effect of CD8⁺ cytotoxic T cells through TAMs depletion.

Protective role of p53 in acetaminophen hepatotoxicity

p53 is a tumor suppressor with a pro-death role in many conditions. However, in some contexts, evidence supports a pro-survival function. p53 has been shown to be activated in acetaminophen (APAP) toxicity but the impact of this on toxicity is uncertain. In the present study, we have found that p53 plays a protective role in APAP-induced liver injury. We inhibited p53 using three different approaches in mice, pifithrin-α (PFTα), knockdown of p53 expression with antisense oligonucleotide, and p53 knockout. Mice were treated with APAP (300mg/kg) i.p. and after 24h in all three conditions, the liver injury was more severe as reflected in higher ALT levels and great area of necrosis in histology of the liver. Conversely, a p53 activator, nutlin-3a, decreased the liver injury induced by APAP. In the p53 inhibition models, enhanced sustained JNK activation was seen in the early time course, while the JNK was suppressed with the p53 activator. In conclusion, p53 plays a novel protective role in APAP induced liver injury through inhibiting the activation of JNK, a key mediator in APAP-induced oxidative stress.

A small-molecule IRF3 agonist functions as an influenza vaccine adjuvant by modulating the antiviral immune response

Vaccine adjuvants are essential to drive a protective immune response in cases where vaccine antigens are weakly immunogenic, where vaccine antigen is limited, or where an increase in potency is needed for a specific population, such as the elderly. To discover novel vaccine adjuvants, we used a high-throughput screen (HTS) designed to identify small-molecule agonists of the RIG-I-like receptor (RLR) pathway leading to interferon regulatory factor 3 (IRF3) activation. RLRs are a group of cytosolic pattern-recognition receptors that are essential for the recognition of viral nucleic acids during infection. Upon binding of viral nucleic acid ligands, the RLRs become activated and signal to transcription factors, including IRF3, to initiate an innate immune transcriptional program to control virus infection. Among our HTS hits were a series of benzothiazole compounds from which we designed the lead analog, KIN1148. KIN1148 induced dose-dependent IRF3 nuclear translocation and specific activation of IRF3-responsive promoters. Prime-boost immunization of mice with a suboptimal dose of a monovalent pandemic influenza split virus H1N1 A/California/07/2009 vaccine plus KIN1148 protected against a lethal challenge with mouse-adapted influenza virus (A/California/04/2009) and induced an influenza virus-specific IL-10 and Th2 response by T cells derived from lung and lung-draining lymph nodes. Prime-boost immunization with vaccine plus KIN1148, but not prime immunization alone, induced antibodies capable of inhibiting influenza virus hemagglutinin and neutralizing viral infectivity. Nevertheless, a single immunization with vaccine plus KIN1148 provided increased protection over vaccine alone and reduced viral load in the lungs after challenge. These findings suggest that protection was at least partially mediated by a cellular immune component and that the induction of Th2 and immunoregulatory cytokines by a KIN1148-adjuvanted vaccine may be particularly beneficial for ameliorating the immunopathogenesis that is associated with influenza viruses.

Restless legs syndrome augmentation among Japanese patients receiving pramipexole therapy: Rate and risk factors in a retrospective study

To investigate the rate of and risk factors for restless legs syndrome (RLS) augmentation in Japanese patients receiving pramipexole (PPX) treatment. Records of 231 consecutive patients with idiopathic RLS who received PPX therapy for more than one month in a single sleep disorder center were analyzed retrospectively. Augmentation was diagnosed based on the Max Planck Institute criteria; associated factors were identified by logistic regression analysis. Mean age at PPX initiation was 60.6 ± 14.9 years and mean treatment duration was 48.5 ± 26.4 months. Augmentation was diagnosed in 21 patients (9.1%). Daily PPX dose and treatment duration were significantly associated with augmentation. By analyzing the receiver operating characteristic curve, a PPX dose of 0.375 mg/day was found to be the optimal cut-off value for predicting augmentation. After stratifying patients according to PPX treatment duration, at median treatment duration of 46 months, optimal cut-off values for daily doses were 0.375 and 0.500 mg/day for <46 months and ≥46 months of treatment, respectively. The RLS augmentation with PPX treatment in Japanese patients was occurred at rate of 9.1%, being quite compatible with previously reported rates in Caucasian patients. The symptom could appear within a relatively short period after starting the treatment in possibly vulnerable cases even with a smaller drug dose. Our results support the importance of keeping doses of PPX low throughout the RLS treatment course to prevent augmentation.

DRP-1 is required for BH3 mimetic-mediated mitochondrial fragmentation and apoptosis

The concept of using BH3 mimetics as anticancer agents has been substantiated by the efficacy of selective drugs, such as Navitoclax and Venetoclax, in treating BCL-2-dependent haematological malignancies. However, most solid tumours depend on MCL-1 for survival, which is highly amplified in multiple cancers and a major factor determining chemoresistance. Most MCL-1 inhibitors that have been generated so far, while demonstrating early promise in vitro, fail to exhibit specificity and potency in a cellular context. To address the lack of standardised assays for benchmarking the in vitro binding of putative inhibitors before analysis of their cellular effects, we developed a rapid differential scanning fluorimetry (DSF)-based assay, and used it to screen a panel of BH3 mimetics. We next contrasted their binding signatures with their ability to induce apoptosis in a MCL-1 dependent cell line. Of all the MCL-1 inhibitors tested, only A-1210477 induced rapid, concentration-dependent apoptosis, which strongly correlated with a thermal protective effect on MCL-1 in the DSF assay. In cells that depend on both MCL-1 and BCL-XL, A-1210477 exhibited marked synergy with A-1331852, a BCL-XL specific inhibitor, to induce cell death. Despite this selectivity and potency, A-1210477 induced profound structural changes in the mitochondrial network in several cell lines that were not phenocopied following MCL-1 RNA interference or transcriptional repression, suggesting that A-1210477 induces mitochondrial fragmentation in an MCL-1-independent manner. However, A-1210477-induced mitochondrial fragmentation was dependent upon DRP-1, and silencing expression levels of DRP-1 diminished not just mitochondrial fragmentation but also BH3 mimetic-mediated apoptosis. These findings provide new insights into MCL-1 ligands, and the interplay between DRP-1 and the anti-apoptotic BCL-2 family members in the regulation of apoptosis.

Pregabalin for the Treatment of Restless Legs Syndrome

OBJECTIVE

To evaluate the efficacy and safety of pregabalin for the treatment of restless legs syndrome (RLS).

DATA SOURCES

A search of the MEDLINE database (1956-February 2016) and EMBASE (1957-February 2016) was conducted, using the terms pregabalin and restless legs syndrome In addition, a manual review of the references cited in each publication identified from the database search was conducted to identify relevant articles.

STUDY SELECTION AND DATA EXTRACTION

All English-language, peer-reviewed publications were evaluated for relevance. From an initial review of 285 articles, 5 clinical trials were included in the final analysis.

DATA SYNTHESIS

Pregabalin is an analog of γ-aminobutyric acid that exhibits antinociceptive and anticonvulsant activity by binding to voltage-gated calcium channels in the central nervous system. Studies of pregabalin have demonstrated efficacy through significant reductions in mean International RLS Scale scores and wake after sleep onset scores, and it had a lower rate of augmentation than pramipexole treatment. Study durations ranged from 6 to 52 weeks, with doses ranging from 150 to 600 mg daily. The most common adverse effects associated with pregabalin use in all studies included dizziness and somnolence.

CONCLUSIONS

Clinical evidence suggests that pregabalin may improve symptoms of RLS and reduce disturbances in sleep, resulting in improvements in quality of life for patients affected by the disease. Pregabalin is considered to be relatively safe and poses a minimal risk of augmentation unlike current recommended first-line treatments for RLS. Thus, evidence suggests that pregabalin is a reasonable therapeutic option for the treatment of RLS.

Inhibition of hippocampal plasticity in rats performing contrafreeloading for water under repeated administrations of pramipexole

RATIONALE

Compulsive symptoms develop in patients exposed to pramipexole (PPX), a dopaminergic agonist with high selectivity for the D3 receptor. Consistently, we demonstrated that PPX produces an exaggerated increase in contrafreeloading (CFL) for water, a repetitive and highly inflexible behavior that models core aspects of compulsive disorders.

OBJECTIVES

Given the role of the hippocampus in behavioral flexibility, motivational control, and visuospatial working memory, we investigated the role of hippocampus in the expression of PPX-induced CFL. To this aim, rats were subjected to CFL under chronic PPX, and then examined for the electrophysiological, structural, and molecular properties of their hippocampus.

METHODS

We measured long-term potentiation (LTP) at CA1 Schaffer collaterals, dendritic spine density in CA1 pyramidal neurons, and then glutamate release and expression of pre and postsynaptic proteins in hippocampal synaptosomes. The effects of PPX on hippocampal-dependent working memory were assessed through the novel object recognition (NOR) test.

RESULTS

We found that PPX-treated rats showing CFL exhibited a significant decrease in hippocampal LTP and failed to exhibit the expected increase in hippocampal spine density. Glutamate release and PSD-95 expression were decreased, while pSYN expression was increased in hippocampal synaptosomes of PPX-treated rats showing CFL. Despite a general impairment of hippocampal synaptic function, working memory was unaffected by PPX treatment.

CONCLUSIONS

Our findings demonstrate that chronic PPX affects synaptic function in the hippocampus, an area that is critically involved in the expression of flexible, goal-centered behaviors. We suggest that the hippocampus is a promising target in the pharmacotherapy of compulsive disorders.

Rotigotine transdermal system as add-on to oral dopamine agonist in advanced Parkinson's disease: an open-label study

BACKGROUND

Achieving optimal symptom control with minimal side effects is a major goal in clinical practice. Dual-agent dopamine receptor agonist (DA) therapy in Parkinson's disease (PD) may represent a promising approach to treatment, as the combination of different pharmacokinetic/pharmacological profiles may result in a lesser need for high dosages and, accordingly, may be well tolerated. The objective of the current study was to investigate safety and efficacy of rotigotine transdermal system as add-on to oral DA in patients with advanced PD inadequately controlled with levodopa and low-dose oral DA.

METHODS

PD0015 was an open-label, multinational study in patients with advanced-PD and sleep disturbance or early-morning motor impairment. Patients were titrated to optimal dose rotigotine (≤8 mg/24 h) over 1-4 weeks and maintained for 4-7 weeks (8-week treatment). Dosage of levodopa and oral DA (pramipexole ≤1.5 mg/day, ropinirole ≤6.0 mg/day) was stable. Primary variable was Clinical Global Impressions (CGI) item 4: side effects, assessing safety. Other variables included adverse events (AEs), Patient Global Impressions of Change (PGIC), Unified Parkinson's Disease Rating Scale (UPDRS) II and III, Parkinson's Disease Sleep Scale (PDSS-2), Pittsburgh Sleep Quality Index (PSQI), and "off" time.

RESULTS

Of 90 patients who received rotigotine, 79 (88%) completed the study; 5 (6%) withdrew due to AEs. Most (83/89; 93%) had a CGI-4 score <3 indicating that rotigotine add-on therapy did not interfere with functioning; 6 (7%) experienced drug-related AEs that interfered with functioning (score ≥3). AEs occurring in ≥5% were application site pruritus (13%), dizziness (10%), orthostatic hypotension (10%), nausea (8%), dyskinesia (8%), and nasopharyngitis (6%). Numerical improvements in motor function (UPDRS III), activities of daily living (UPDRS II), sleep disturbances (PDSS-2, PSQI), and reduction in "off" time were observed. The majority (71/88; 81%) improved on PGIC.

CONCLUSIONS

Addition of rotigotine transdermal system to low-dose oral DA in patients with advanced-PD was feasible and may be associated with clinical benefit.

TRIAL REGISTRATION

ClinicalTrials.gov identifier NCT01723904 . Trial registration date: November 6, 2012.

[Dyskinesia-hyperpyrexia syndrome in a patient with Parkinson's disease: a case report]

Non-physiological, excessive dopaminergic stimulation can cause dyskinesia-hyperpyrexia syndrome (DHS), which was initially reported by Gil-Navarro and Grandas in 2010. A 70-years-old woman with a 13-years history of Parkinson's disease (PD) was hospitalized due to difficulty walking, despite being treated with levodopa/carbidopa (600 mg/day), immediate-release pramipexole (3 mg/day), and selegiline (5 mg/day). Immediate-release pramipexole was changed to extended-release pramipexole without changing the dose or levodopa equivalent dose (LED). The patient's adherence to drugs was good. The parkinsonism gradually improved and the patient was discharged. One month later, the patient developed severe generalized athetotic dyskinesia with visual hallucinations and hyperpyrexia that lasted for a week, and she was readmitted to hospital. On admission, the patient was conscious but slightly disoriented. Body temperature was 40.3°C with hyperhidrosis. Leukocyte count in the peripheral blood was 1.78×10(4)/ml and serum creatine kinase was >3×10(4) U/l. Chest survey, whole-body computed tomography, and cranial magnetic resonance imaging showed no abnormalities. The patient was diagnosed with DHS and treated by tapering the oral administration of dopaminergic drugs, including extended-release pramipexole. Her clinical condition recovered without dyskinesia, and serum creatine kinase level swiftly normalized. DHS and resemblant conditions are reported to occur in long-term PD patients with motor complications. In advanced stage PD, loss of dopaminergic neurons impairs the dopamine holding capacity of the striatum and exogenous dopaminergic drugs can result in uncontrollable and excessive fluctuations in dopamine concentration. Our case recommends caution when switching to long-acting dopaminergic drugs, even if the dose is unchanged, could lead to excessive dopaminergic stimulation. This case highlights the importance of considering both the LED and the duration of action of dopaminergic drugs when adjusting medication.

Activation of KCa3.1 by SKA-31 induces arteriolar dilatation and lowers blood pressure in normo- and hypertensive connexin40-deficient mice

BACKGROUND AND PURPOSE

The calcium-activated potassium channel KCa3.1 is expressed in the vascular endothelium where its activation causes endothelial hyperpolarization and initiates endothelium-derived hyperpolarization (EDH)-dependent dilatation. Here, we investigated whether pharmacological activation of KCa3.1 dilates skeletal muscle arterioles and whether myoendothelial gap junctions formed by connexin40 (Cx40) are required for EDH-type dilatations and pressure depressor responses in vivo.

EXPERIMENTAL APPROACH

We performed intravital microscopy in the cremaster muscle microcirculation and blood pressure telemetry in Cx40-deficient mice.

KEY RESULTS

In wild-type mice, the KCa3.1-activator SKA-31 induced pronounced concentration-dependent arteriolar EDH-type dilatations, amounting to ∼40% of maximal dilatation, and enhanced the effects of ACh. These responses were absent in mice devoid of KCa3.1 channels. In contrast, SKA-31-induced dilatations were not attenuated in mice with endothelial cells deficient in Cx40 (Cx40(fl/fl):Tie2-Cre). In isolated endothelial cell clusters, SKA-31 induced hyperpolarizations of similar magnitudes (by ∼38 mV) in Cx40(fl/fl):Tie2-Cre, ubiquitous Cx40-deficient mice (Cx40(-/-)) and controls (Cx40(fl/fl)), which were reversed by the specific KCa3.1-blocker TRAM-34. In normotensive wild-type and Cx40(fl/fl):Tie2-Cre as well as in hypertensive Cx40(-/-) animals, i.p. injections of SKA-31 (30 and 100 mg·kg(-1)) decreased arterial pressure by ∼32 mmHg in all genotypes. The depressor response to 100 mg·kg(-1) SKA-31 was associated with a decrease in heart rate.

CONCLUSIONS AND IMPLICATIONS

We conclude that endothelial hyperpolarization evoked by pharmacological activation of KCa3.1 channels induces EDH-type arteriolar dilatations that are independent of endothelial Cx40 and Cx40-containing myoendothelial gap junctions. As SKA-31 reduced blood pressure in hypertensive Cx40-deficient mice, KCa3.1 activators may be useful drugs for severe treatment-resistant hypertension.

The FLT3 inhibitor quizartinib inhibits ABCG2 at pharmacologically relevant concentrations, with implications for both chemosensitization and adverse drug interactions

The oral second-generation bis-aryl urea fms-like tyrosine kinase 3 (FLT3) inhibitor quizartinib (AC220) has favorable kinase selectivity and pharmacokinetics. It inhibits mutant and wild-type FLT3 in vivo at 0.1 and 0.5 µM, respectively, and has shown favorable activity and tolerability in phase I and II trials in acute myeloid leukemia, with QT prolongation as the dose-limiting toxicity. Co-administration with chemotherapy is planned. We characterized interactions of quizartinib with the ATP-binding cassette (ABC) proteins ABCB1 (P-glycoprotein) and ABCG2 (breast cancer resistance protein). Its effects on uptake of fluorescent substrates and apoptosis were measured by flow cytometry, binding to ABCB1 and ABCG2 drug-binding sites by effects on [¹²⁵I]iodoarylazidoprazosin ([¹²⁵I]-IAAP) photolabeling and ATPase activity, and cell viability by the WST-1 colorimetric assay. Quizartinib inhibited transport of fluorescent ABCG2 and ABCB1 substrates in ABCG2- and ABCB1-overexpressing cells in a concentration-dependent manner, from 0.1 to 5 µM and from 0.5 to 10 µM, respectively, and inhibited [¹²⁵I]-IAAP photolabeling of ABCG2 and ABCB1 with IC₅₀ values of 0.07 and 3.3 µM, respectively. Quizartinib at higher concentrations decreased ABCG2, but not ABCB1, ATPase activity. Co-incubation with quizartinib at 0.1 to 1 µM sensitized ABCG2-overexpressing K562/ABCG2 and 8226/MR20 cells to ABCG2 substrate chemotherapy drugs in a concentration-dependent manner in cell viability and apoptosis assays. Additionally, quizartinib increased cellular uptake of the ABCG2 substrate fluoroquinolone antibiotic ciprofloxacin, which also prolongs the QT interval, in a concentration-dependent manner, predicting altered ciprofloxacin pharmacokinetics and pharmacodynamics when co-administered with quizartinib. Thus quizartinib inhibits ABCG2 at pharmacologically relevant concentrations, with implications for both chemosensitization and adverse drug interactions. These interactions should be considered in the design of treatment regimens combining quizartinib and chemotherapy drugs and in choice of concomitant medications to be administered with quizartinib.

Effect of p53 inhibition by pifithrin-alpha on functional activity of vasopressin neurones in rat hypothalamus

In the present work we investigated the effects of p53 inhibition by pifithrin-alpha (PFT) in vitro and in vivo on functioning vasopressinergic magnocellular neurones of rat hypothalamus. In vivo treatments with PFT were done by intra-hypothalamic microinjections or by intra peritoneal injections. In in vitro experiments hypothalamic slices containing supraoptic nuclei and intact pituitary were incubated with or without PFT. In all experiments we observed accumulation of vasopressin (VP) in the cell perikarya after PFT injections, however expression of VP mRNA was not changed. Analysis of VP content in the posterior pituitary demonstrated that amount of VP was significantly decreased after PFT treatments. Additionally, long-term inhibition of p53 in experiments with intra-hypothalamic injections of PFT resulted in an increased diuresis rate. The obtained results demonstrated that in all experiments PFT treatments inhibited VP anterograde transport from the cells of supraoptic nuclei. Moreover, analysis of MEK/ERK activities revealed that phosphorylation levels of MEK1/2 and ERK1/2 were decreased after PFT treatments. Our findings provide new evidences that p53 could be involved in the control of VP secretion from hypothalamo-hypophyseal system and that this action probably can be mediated by ERK signalling pathway.

Factors affecting the efficacy of pramipexole in patients with restless legs syndrome

Dopamine agonists, particularly nonergot dopamine agonists such as pramipexole, have become the mainstay of therapy for patients with symptoms of restless legs syndrome (RLS). This study was designed to evaluate the factors affecting the efficacy of pramipexole in patients with RLS. Fifty-nine eligible RLS patients referred to neurology clinic of Rasoul-e-Akram Hospital (Tehran, Iran) were recruited in this study. All of the patients received an oral dose of 0.18 mg pramipexole. The severity of RLS symptoms were evaluated including sleep disorder, symptomatic days per week and symptomatic hours per day, both at the beginning and at the end of follow-up time. Different baseline and follow-up variables were also recorded and their relationships with the outcomes were assessed. The mean severity values of different symptoms significantly decreased after treatment with pramipexole (P&lt;0.001). Female gender (P&lt;0.05) and duration of treatment (P&lt;0.05) were significant factors to achieve &gt;50% reduction in symptomatic days per week and symptomatic hours per day. Moreover, the cutoff point of 3.5 mo for duration of treatment could potentially differentiate &gt;50% reduction in severity of sleep disorder from the ones with &lt;50% reduction with sensitivity and specificity of 56.8% and 78.6%, respectively. Our findings show that female gender and duration of treatment were the factors affecting the effectiveness of pramipexole in RLS patients. If tolerated by the patients, a longer duration of treatment with pramipexole is more effective in RLS.

A randomized, double-blind, placebo-controlled trial of pramipexole augmentation in treatment-resistant major depressive disorder

BACKGROUND

Multiple treatments for patients with major depressive disorder (MDD) have demonstrated efficacy, but up to one-third of individuals with MDD do not achieve symptomatic remission despite various interventions. Existing augmentation or combination strategies can have substantial safety concerns that may limit their application.

METHOD

This study investigated the antidepressant efficacy of a flexible dose of the dopamine agonist pramipexole as an adjunct to standard antidepressant treatment in an 8-week, randomized, double-blind, placebo-controlled trial conducted in a tertiary-level depression center. We randomized 60 outpatients (aged 18 to 75 years) with treatment-resistant nonpsychotic MDD (diagnosed according to DSM-IV) to either pramipexole (n = 30) or placebo (n = 30). Treatment resistance was defined as continued depression (Montgomery-Asberg Depression Rating Scale [MADRS] score ≥ 18) despite treatment with at least 1 prior antidepressant in the current depressive episode. Patients were recruited between September 2005 and April 2008. The primary outcome measure was the MADRS score.

RESULTS

The analyses that used a mixed-effects linear regression model indicated a modest but statistically significant benefit for pramipexole (P = .038). The last-observation-carried-forward analyses indicated that 40% and 33% of patients randomized to augmentation with pramipexole achieved response (χ(2) = 1.2, P = .27) and remission (χ(2) = 0.74, P = .61), respectively, compared to 27% and 23% with placebo; however, those differences were not statistically significant. Augmentation with pramipexole was well-tolerated, with no serious adverse effects identified.

CONCLUSION

For patients who have failed to respond to standard antidepressant therapies, pramipexole is a safe and potentially efficacious augmentation strategy.

TRIAL REGISTRATION

ClinicalTrials.gov identifier: NCT00231959.

Efficacy and safety of AZD3199 vs formoterol in COPD: a randomized, double-blind study

BACKGROUND

We investigated the efficacy and safety of AZD3199, a novel inhaled ultra-LABA, with the main aim of establishing a dose that would maintain 24-hour bronchodilation in patients with COPD.

METHODS

Patients (n = 329) were randomized to AZD3199 (200, 400 or 800 μg o.d.), formoterol (9 μg b.i.d.) or placebo via Turbuhaler® in a parallel group study. The primary objective of the study was to compare the clinical efficacy of three doses of AZD3199 inhaled once daily with 9 μg formoterol twice daily and placebo, over a 4-week treatment period in adults with moderate-to-severe COPD. After 4 weeks, peak (0-4 h) and trough (24-26 h) forced expiratory volume in 1 second (FEV1) were assessed as the primary efficacy outcome variables.

RESULTS

All AZD3199 doses significantly increased mean peak and trough FEV1 versus placebo (106-171 ml and 97-110 ml increases, respectively), but with no clear dose-response; the level of bronchodilation was comparable to or greater than that achieved with formoterol. Forced vital capacity (FVC) at peak bronchodilation also significantly increased with AZD3199 versus placebo (153-204 ml). COPD symptom scores and reliever use were reduced with AZD3199, while FEV1 reversibility was unaltered. Adverse events were mild-to-moderate, with no safety concerns identified. Drug exposure was dose-proportional, but lower than predicted from healthy volunteers.

CONCLUSIONS

All three doses of AZD3199 produced 24-hour bronchodilation, but with no clear dose-response, suggesting that doses of 200 μg or less may be sufficient to maintain bronchodilation over 24 hours in patients with COPD. No safety concerns were identified. Further studies are required to determine the once-daily AZD3199 dose for COPD.

TRIAL REGISTRATION

Clinicaltrials.gov, NCT00929708.

[Inactivation of p53 leads to enhancement of tyrosine hydroxylase biosynthesis in the dopaminergic brain neurons]

In the present work we analyzed a possibility of interaction of protein p53, family members of the ERK1/2 signaling cascade, and the transcription factor CREB in regulation of functional activity of dopaminergic neurons. There were considered neurons of Substantia nigra and Zona incerta of control rats and of rats injected intraperitoneally with chemical inhibitor of p53 Pifithrin-alpha blocking transcription activity ofproapoptotic protein p53. We have shown the p53 inactivation to lead to an increase in the content of tyrosine'hydroxylase both in cell bodies and in terminal parts of axons. At the same time, activity of the transcription factor CREB is enhanced in the brain dopaminergic neurons. No significant differences in the content of phospho-ERK1/2 kinases were revealed in the cell bodies at use of Pifithrin-alpha as compared with control group. Thus, we have shown that action of p53 on biosynthesis of tyrosine hydroxylase is of inhibitory character and seems to be mediated by the transcription factor CREB.

Evaluation of the efficacy of pramipexole for treating levodopa-induced dyskinesia in patients with Parkinson's disease

OBJECTIVE

The long-term use of levodopa to treat Parkinson's disease (PD) is often limited by the development of motor complications (e.g., levodopa-induced dyskinesia, LID). We hypothesized that a non-ergot dopamine agonist with strong affinity for D3) dopamine receptors (pramipexole) may improve LID in patients taking an ergot D1/D2 dopamine agonist.

METHODS

Patients with PD and LID being treated with levodopa in addition to an ergot dopamine agonist were randomized to either a group in which pramipexole was added to current medications or a group in which the ergot dopamine agonist was switched to pramipexole. Dyskinesia was evaluated using Core Assessment Program for Surgical Interventional Therapies scores. The unified Parkinson's disease rating scale scores, modified Hoehn and Yahr stages (at 'on' time), Parkinson's disease questionnaire-39 scores and clinical global impression-improvement scores were also used for evaluation.

RESULTS

At 24 weeks, pramipexole alleviated LID with more efficiency in the switch group.

CONCLUSION

Pramipexole may be a therapeutic option for treating LID because its effects on D3 dopamine receptors may balance the D1 dopamine receptor supersensitivity associated with LID.

Evaluation of the safety and tolerability of rasagiline in the treatment of the early stages of Parkinson's disease

OBJECTIVE

Rasagiline is a second-generation, irreversible MAO-B inhibitor (MAOB-I) previously shown to be efficacious and well-tolerated compared to placebo in the treatment of early Parkinson's disease (PD). ACTOR (ACceptabilité TOlérance Rasagiline) was a 15-week, multi-center, randomized, double-blind study aimed to assess the safety and tolerability of rasagiline compared to the dopaminergic agonist pramipexole in the treatment of early PD.

METHODS

Patients with early, untreated idiopathic PD were randomized to receive 1 mg rasagiline (n = 53) or 1.5 mg pramipexole (n = 56) daily. The primary outcome was the number of patients experiencing a 'clinically important adverse event' (classified as a serious adverse event, an event leading to withdrawal or severe according to the patient). Safety outcomes were evaluated by the investigator and the patient. Analysis of the primary criterion was a comparative analysis using the chi-squared test. The Wilcoxon Mann-Whitney test was conducted to test the severity of patient-reported adverse events. Other tests performed include a covariance analysis and Student's t-tests.

RESULTS

Mean disease duration was 3.4 months, and mean age was 62.6 years. Of patients taking pramipexole, 44.6% reported at least one 'clinically important' adverse event compared to 32.1% of patients taking rasagiline; non-inferiority of rasagiline was reached, with a difference in proportions of -12.6% [confidence interval of -27.8%; 2.6%]. There were no significant differences in clinical effectiveness between the treatments, measured by clinical and patient global impression of improvement (CGI-I, PGI-I) and PDQ-8 scales. A significant decrease in the incidence of gastrointestinal symptoms (p = 0.015) and sleep disorders (p = 0.027) was reported by physicians in the rasagiline group compared to the pramipexole group; the propensity to sleepiness improved significantly in the rasagiline group (p = 0.020), and worsened in the pramipexole group (p = 0.042).

LIMITATIONS

Limitations of this study include the limited sample size due to the lower than anticipated recruitment and the accidental inclusion of a patient who had taken contraindicated medication.

CONCLUSIONS

In this study, the safety profile of rasagiline had clinically favorable differences in gastrointestinal and sleep adverse events compared to pramipexole, whilst showing comparable clinician and patient-rated clinical effectiveness as a monotherapy for the treatment of early idiopathic PD.

Genetic KCa3.1-deficiency produces locomotor hyperactivity and alterations in cerebral monoamine levels

Background

The calmodulin/calcium-activated K⁺ channel KCa3.1 is expressed in red and white blood cells, epithelia and endothelia, and possibly central and peripheral neurons. However, our knowledge about its contribution to neurological functions and behavior is incomplete. Here, we investigated whether genetic deficiency or pharmacological activation of KCa3.1 change behavior and cerebral monoamine levels in mice.

Methodology/Principal Findings

In the open field test, KCa3.1-deficiency increased horizontal activity, as KCa3.1^−/− mice travelled longer distances (≈145% of KCa3.1^+/+) and at higher speed (≈1.5-fold of KCa3.1^+/+). Working memory in the Y-maze was reduced by KCa3.1-deficiency. Motor coordination on the rotarod and neuromuscular functions were unchanged. In KCa3.1^−/− mice, HPLC analysis revealed that turn-over rates of serotonin were reduced in frontal cortex, striatum and brain stem, while noradrenalin turn-over rates were increased in the frontal cortex. Dopamine turn-over rates were unaltered. Plasma catecholamine and corticosterone levels were unaltered. Intraperitoneal injections of 10 mg/kg of the KCa3.1/KCa2-activator SKA-31 reduced rearing and turning behavior in KCa3.1^+/+ but not in KCa3.1^−/− mice, while 30 mg/kg SKA-31 caused strong sedation in 50% of the animals of either genotypes. KCa3.1^−/− mice were hyperactive (≈+60%) in their home cage and SKA-31-administration reduced nocturnal physical activity in KCa3.1^+/+ but not in KCa3.1^−/− mice.

Conclusions/Significance

KCa3.1-deficiency causes locomotor hyperactivity and altered monoamine levels in selected brain regions, suggesting a so far unknown functional link of KCa3.1 channels to behavior and monoaminergic neurotransmission in mice. The tranquilizing effects of low-dose SKA-31 raise the possibility to use KCa3.1/KCa2 channels as novel pharmacological targets for the treatment of neuropsychiatric hyperactivity disorders.

Phase II study of first-line sagopilone plus prednisone in patients with castration-resistant prostate cancer: a phase II study of the Department of Defense Prostate Cancer Clinical Trials Consortium

BACKGROUND

Preclinical studies in prostate cancer (PC) models demonstrated the anti-tumour activity of the first fully synthetic epothilone, sagopilone. This is the first study to investigate the activity and safety of sagopilone in patients with metastatic castration-resistant PC (CRPC).

METHODS

Chemotherapy-naïve patients with metastatic CRPC received sagopilone (one cycle: 16 mg m(-2) intravenously over 3 h q3w) plus prednisone (5 mg twice daily). The primary efficacy evaluation was prostate-specific antigen (PSA) response rate (≥50% PSA reduction confirmed ≥28 days apart). According to the Simon two-stage design, ≥3 PSA responders were necessary within the first 13 evaluable patients for recruitment to continue until 46 evaluable patients were available.

RESULTS

In all, 53 patients received ≥2 study medication cycles, with high compliance. Mean individual dose was 15.1±1.4 mg m(-2) during initial six cycles, mean dose intensity 94±9%. The confirmed PSA response rate was 37%. Median overall progression-free survival was 6.4 months. The most commonly reported adverse events (>10% of patients) were peripheral neuropathy (94.3%), fatigue (54.7%) and pain in the extremities (47.2%). Sagopilone was associated with very little haematological toxicity.

CONCLUSION

This study shows that first-line sagopilone has noteworthy anti-tumour activity and a clinically significant level of neuropathy for patients with metastatic chemotherapy-naïve CRPC.

Synthesis and pharmacological characterization of a novel sigma receptor ligand with improved metabolic stability and antagonistic effects against methamphetamine

Methamphetamine interacts with sigma receptors at physiologically relevant concentrations suggesting a potential site for pharmacologic intervention. In the present study, a previous sigma receptor ligand, CM156, was optimized for metabolic stability, and the lead analog was evaluated against the behavioral effects of methamphetamine. Radioligand binding studies demonstrated that the lead analog, AZ66, displayed high nanomolar affinity for both sigma-1 and sigma-2 receptors (2.4 ± 0.63 and 0.51 ± 0.15, respectively). In addition, AZ66 had preferential affinity for sigma receptors compared to seven other sites and a significantly longer half-life than its predecessor, CM156, in vitro and in vivo. Pretreatment of male, Swiss Webster mice with intraperitoneal (10-20 mg/kg) or oral (20-30 mg/kg) dosing of AZ66 significantly attenuated the acute locomotor stimulatory effects of methamphetamine. Additionally, AZ66 (10-20 mg/kg, i.p.) significantly reduced the expression and development of behavioral sensitization induced by repeated methamphetamine administration. Taken together, these data indicate that sigma receptors can be targeted to mitigate the acute and subchronic behavioral effects of methamphetamine and AZ66 represents a viable lead compound in the development of novel therapeutics against methamphetamine-induced behaviors.

Phase I/II study of sagopilone (ZK-EPO) plus carboplatin in women with recurrent platinum-sensitive ovarian cancer

BACKGROUND

Sagopilone is the first fully synthetic epothilone in clinical development and has demonstrated promising preclinical activity. This phase I/II, prospective, open-label trial investigated the efficacy and safety of sagopilone plus carboplatin in patients with recurrent platinum-sensitive ovarian cancer (OC).

METHODS

In phase I (dose-escalation stage), patients with OC recurring at least 6 months after platinum-containing chemotherapy received 3-h infusions of sagopilone (initial dose of 12 mg m(-2)) followed by carboplatin every 3 weeks, for 2-6 treatment courses. Patients enrolled in phase II received 3-h infusions of 16 mg m(-2) sagopilone. Efficacy was assessed using modified Response Evaluation Criteria in Solid Tumors (modRECIST) and Gynecologic Cancer InterGroup CA125 criteria. The safety and tolerability of sagopilone were also evaluated.

RESULTS

In all, 45 patients received sagopilone at 12 mg m(-2) or 16 mg m(-2). There were 29 confirmed tumour responses (21 modRECIST and 8 CA125) across both treatment groups, indicating that the primary objective of the study was reached. The main adverse events (AEs) reported were peripheral neuropathy (75.6%), fatigue (71.1%) and nausea (64.4%). Grade ≥3 AEs occurred in 35 patients (77.8%). No deaths related to the study drug were reported.

CONCLUSION

Sagopilone in combination with carboplatin was effective and toxicities were manageable in patients with recurrent platinum-sensitive OC.

Benzothiazole toxicity assessment in support of synthetic turf field human health risk assessment

Synthetic turf fields cushioned with crumb rubber may be a source of chemical exposure to those playing on the fields. Benzothiazole (BZT) may volatilize from crumb rubber and result in inhalation exposure. Benzothiazole has been the primary rubber-related chemical found in synthetic turf studies. However, risks associated with BZT have not been thoroughly assessed, primarily because of gaps in the database. This assessment provides toxicity information for a human health risk assessment involving BZT detected at five fields in Connecticut. BZT exerts acute toxicity and is a respiratory irritant and dermal sensitizer. In a genetic toxicity assay BZT was positive in Salmonella in the presence of metabolic activation. BZT metabolism involves ring-opening and formation of aromatic hydroxylamines, metabolites with mutagenic and carcinogenic potential. A structural analogue 2-mercaptobenzothiazole (2-MBZT) was more widely tested and so is used as a surrogate for some endpoints. 2-MBZT is a rodent carcinogen with rubber industry data supporting an association with human bladder cancer. The following BZT toxicity values were derived: (1) acute air target of 110 μg/m(3) based upon a BZT RD(50) study in mice relative to results for formaldehyde; (2) a chronic noncancer target of 18 μg/m(3) based upon the no-observed-adverse-effect level (NOAEL) in a subchronic dietary study in rats, dose route extrapolation, and uncertainty factors that combine to 1000; (3) a cancer unit risk of 1.8E-07/μg-m(3) based upon a published oral slope factor for 2-MBZT and dose-route extrapolation. While there are numerous uncertainties in the BZT toxicology database, this assessment enables BZT to be quantitatively assessed in risk assessments involving synthetic turf fields. However, this is only a screening-level assessment, and research that better defines BZT potency is needed.

Human health risk assessment of synthetic turf fields based upon investigation of five fields in Connecticut

Questions have been raised regarding possible exposures when playing sports on synthetic turf fields cushioned with crumb rubber. Rubber is a complex mixture with some components possessing toxic and carcinogenic properties. Exposure is possible via inhalation, given that chemicals emitted from rubber might end up in the breathing zone of players and these players have high ventilation rates. Previous studies provide useful data but are limited with respect to the variety of fields and scenarios evaluated. The State of Connecticut investigated emissions associated with four outdoor and one indoor synthetic turf field under summer conditions. On-field and background locations were sampled using a variety of stationary and personal samplers. More than 20 chemicals of potential concern (COPC) were found to be above background and possibly field-related on both indoor and outdoor fields. These COPC were entered into separate risk assessments (1) for outdoor and indoor fields and (2) for children and adults. Exposure concentrations were prorated for time spent away from the fields and inhalation rates were adjusted for play activity and for children's greater ventilation than adults. Cancer and noncancer risk levels were at or below de minimis levels of concern. The scenario with the highest exposure was children playing on the indoor field. The acute hazard index (HI) for this scenario approached unity, suggesting a potential concern, although there was great uncertainty with this estimate. The main contributor was benzothiazole, a rubber-related semivolatile organic chemical (SVOC) that was 14-fold higher indoors than outdoors. Based upon these findings, outdoor and indoor synthetic turf fields are not associated with elevated adverse health risks. However, it would be prudent for building operators to provide adequate ventilation to prevent a buildup of rubber-related volatile organic chemicals (VOC) and SVOC at indoor fields. The current results are generally consistent with the findings from studies conducted by New York City, New York State, the U.S. Environmental Protection Agency (EPA), and Norway, which tested different kinds of fields and under a variety of weather conditions.

Recurrence of cluster headache with pramipexole

Cluster headache (CH) is among the most painful headache disorders. There is still no unifying pathophysiological hypothesis to explain the trigeminal distribution, the circadian periodicity and the autonomic symptoms of the syndrome. We report the case of a patient with worsening of CH following administration of pramipexole for a restless legs syndrome (RLS). This observation supports the hypothesis that the dopaminergic system may play a role in the genesis or trigger of CH.