Effect of Deutetrabenazine on Chorea Among Patients With Huntington Disease A Randomized Clinical Trial

Importance Deutetrabenazine is a novel molecule containing deuterium, which attenuates CYP2D6 metabolism and increases active metabolite half-lives and may therefore lead to stable systemic exposure while preserving key pharmacological activity. Objective To evaluate efficacy and safety of deutetrabenazine treatment to control chorea associated with Huntington disease. Design, Setting, and Participants Ninety ambulatory adults diagnosed with manifest Huntington disease and a baseline total maximal chorea score of 8 or higher (range, 0-28; lower score indicates less chorea) were enrolled from August 2013 to August 2014 and randomized to receive deutetrabenazine (n = 45) or placebo (n = 45) in a double-blind fashion at 34 Huntington Study Group sites. Interventions Deutetrabenazine or placebo was titrated to optimal dose level over 8 weeks and maintained for 4 weeks, followed by a 1-week washout. Main Outcomes and Measures Primary end point was the total maximal chorea score change from baseline (the average of values from the screening and day-0 visits) to maintenance therapy (the average of values from the week 9 and 12 visits) obtained by in-person visits. This study was designed to detect a 2.7-unit treatment difference in scores. The secondary end points, assessed hierarchically, were the proportion of patients who achieved treatment success on the Patient Global Impression of Change (PGIC) and on the Clinical Global Impression of Change (CGIC), the change in 36-Item Short Form– physical functioning subscale score (SF-36), and the change in the Berg Balance Test. Results Ninety patients with Huntington disease (mean age, 53.7 years; 40 women [44.4%]) were enrolled. In the deutetrabenazine group, the mean total maximal chorea scores improved from 12.1 (95% CI, 11.2-12.9) to 7.7 (95% CI, 6.5-8.9), whereas in the placebo group, scores improved from 13.2 (95% CI, 12.2-14.3) to 11.3 (95% CI, 10.0-12.5); the mean between-group difference was –2.5 units (95% CI, –3.7 to –1.3) (P < .001). Treatment success, as measured by the PGIC, occurred in 23 patients (51%) in the deutetrabenazine group vs 9 (20%) in the placebo group (P = .002). As measured by the CGIC, treatment success occurred in 19 patients (42%) in the deutetrabenazine group vs 6 (13%) in the placebo group (P = .002). In the deutetrabenazine group, the mean SF-36 physical functioning subscale scores decreased from 47.5 (95% CI, 44.3-50.8) to 47.4 (44.3-50.5), whereas in the placebo group, scores decreased from 43.2 (95% CI, 40.2-46.3) to 39.9 (95% CI, 36.2-43.6), for a treatment benefit of 4.3 (95% CI, 0.4 to 8.3) (P = .03). There was no difference between groups (mean difference of 1.0 unit; 95% CI, –0.3 to 2.3; P = .14), for improvement in the Berg Balance Test, which improved by 2.2 units (95% CI, 1.3-3.1) in the deutetrabenazine group and by 1.3 units (95% CI, 0.4-2.2) in the placebo group. Adverse event rates were similar for deutetrabenazine and placebo, including depression, anxiety, and akathisia. Conclusions and Relevance Among patients with chorea associated with Huntington disease, the use of deutetrabenazine compared with placebo resulted in improved motor signs at 12 weeks. Further research is needed to assess the clinical importance of the effect size and to determine longer-term efficacy and safety

Safety, tolerability, and efficacy of PBT2 in Huntington's disease: A phase 2, randomised, double-blind, placebo-controlled trial

Background: PBT2 is a metal protein-attenuating compound that might reduce metal-induced aggregation of mutant huntingtin and has prolonged survival in a mouse model of Huntington's disease. We aimed to assess the safety, tolerability, and efficacy of PBT2 in patients with Huntington's disease. Methods: In this 26-week, randomised, double-blind, placebo-controlled trial, adults ( ≥ 25 years old ) with early-stage to mid-stage Huntington's disease were randomly assigned ( 1:1:1 ) by a centralised interactive response system to once daily PBT2 250 mg, PBT2 100 mg, or placebo. Randomisation was stratified by site with a block size of three. Participants, carers, the steering committee, site investigators, study staff, and the study sponsor were masked to treatment assignment. Primary endpoints were safety and tolerability. The safety population consisted of all participants who were randomly assigned and had at least one dose of study drug. The principal secondary endpoint was cognition, measured by the change from baseline to week 26 in the main composite Z score of five cognitive tests ( Category Fluency Test, Trail Making Test Part B, Map Search, Symbol Digit Modalities Test, and Stroop Word Reading Test ) and scores on eight individual cognitive tests ( the five aforementioned plus the Trail Making Test Part A, Montreal Cognitive Assessment, and the Speeded Tapping Test ). The intention-to-treat population comprised participants who were randomly assigned and had at least one efficacy assessment after administration of study drug. This trial is registered with [http://clinicaltrials.gov/] ClinicalTrials.gov, [http://clinicaltrials.gov/show/NCT01590888] NCT01590888. Findings: Between April 18, 2012, and Dec 14, 2012, 109 participants were randomly assigned to PBT2 250 mg ( n=36 ), PBT2 100 mg ( n=38 ), or placebo ( n=35 ) at 19 research centres in Australia and the USA. 32 ( 89% ) individuals on PBT2 250 mg, 38 ( 100% ) on PBT2 100 mg, and 34 ( 97% ) on placebo completed the study. Six serious adverse events ( acute coronary syndrome, major depression, pneumonia, suicide attempt, viral infection, and worsening of Huntington's disease ) occurred in five participants in the PBT2 250 mg group, three ( fall with subdural haematoma, suicide attempt, and hospital admission for stabilisation of Huntington's disease ) occurred in two participants in the PBT2 100 mg group, and one ( increasing aggression ) occurred in a participant in the placebo group. The site investigators deemed all, except the worsening of Huntington's disease, as unrelated to study drug. 32 ( 89% ) participants on PBT2 250 mg, 30 ( 79% ) on PBT2 100 mg, and 28 ( 80% ) on placebo had at least one adverse event. Compared with placebo, neither PBT2 100 mg ( least-squares mean 0·02, 95% CI −0·10 to 0·14; p=0·772 ) nor PBT2 250 mg ( 0·07, −0·05 to 0·20; p=0·240 ) significantly improved the main composite cognition Zscore between baseline and 26 weeks. Compared with placebo, the Trail Making Test Part B score was improved between baseline and 26 weeks in the PBT2 250 mg group ( 17·65 s, 0·65–34·65; p=0·042 ) but not in the 100 mg group ( 0·79 s improvement, −15·75 to 17·32; p=0·925 ); neither dose significantly improved cognition on the other tests. Interpretation: PBT2 was generally safe and well tolerated in patients with Huntington's disease. The potential benefit on executive function will need to be confirmed in a larger study. Funding: Prana Biotechnology Limited

Beyond Point Masses. II. Non-Keplerian Shape Effects Are Detectable in Several TNO Binaries

About 40 trans-Neptunian binaries (TNBs) have fully determined orbits with about 10 others being solved except for breaking the mirror ambiguity. Despite decades of study, almost all TNBs have only ever been analyzed with a model that assumes perfect Keplerian motion (e.g., two point masses). In reality, all TNB systems are non-Keplerian due to nonspherical shapes, possible presence of undetected system components, and/or solar perturbations. In this work, we focus on identifying candidates for detectable non-Keplerian motion based on sample of 45 well-characterized binaries. We use MultiMoon , a non-Keplerian Bayesian inference tool, to analyze published relative astrometry allowing for nonspherical shapes of each TNB system’s primary. We first reproduce the results of previous Keplerian fitting efforts with MultiMoon , which serves as a comparison for the non-Keplerian fits and confirms that these fits are not biased by the assumption of a Keplerian orbit. We unambiguously detect non-Keplerian motion in eight TNB systems across a range of primary radii, mutual orbit separations, and system masses. As a proof of concept for non-Keplerian fitting, we perform detailed fits for (66652) Borasisi-Pabu, possibly revealing a J _2 ≈ 0.44, implying Borasisi (and/or Pabu) may be a contact binary or an unresolved compact binary. However, full confirmation of this result will require new observations. This work begins the next generation of TNB analyses that go beyond the point mass assumption to provide unique and valuable information on the physical properties of TNBs with implications for their formation and evolution