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IMPORTANCE Ubrogepant is an oral calcitonin gene-related peptide receptor antagonist under investigation for acute treatment of migraine. OBJECTIVE To evaluate the efficacy and tolerability of ubrogepant compared with placebo for acute treatment of a single migraine attack. DESIGN, SETTING, AND PARTICIPANTS Phase 3, multicenter, randomized, double-blind, placebo-controlled, single-attack, clinical trial (ACHIEVE II) conducted in the United States (99 primary care and research clinics; August 26, 2016-February 26, 2018). Participants were adults with migraine with or without aura experiencing 2 to 8 migraine attacks per month. INTERVENTIONS Ubrogepant 50 mg (n = 562), ubrogepant 25 mg (n = 561), or placebo (n = 563) for a migraine attack of moderate or severe pain intensity. MAIN OUTCOMES AND MEASURES Co-primary efficacy outcomes were pain freedom and absence of the participant-designated most bothersome migraine-associated symptom (among photophobia, phonophobia, and nausea) at 2 hours after taking the medication. RESULTS Among 1686 randomized participants, 1465 received study treatment (safety population; mean age, 41.5 years; 90% female); 1355 of 1465 (92.5%) were evaluable for efficacy. Pain freedom at 2 hours was reported by 101 of 464 participants (21.8%) in the ubrogepant 50-mg group, 90 of 435 (20.7%) in the ubrogepant 25-mg group, and 65 of 456 (14.3%) in the placebo group (absolute difference for 50 mg vs placebo, 7.5%; 95% CI, 2.6%-12.5%; P = .01; 25 mg vs placebo, 6.4%; 95% CI, 1.5%-11.5%; P = .03). Absence of the most bothersome associated symptom at 2 hours was reported by 180 of 463 participants (38.9%) in the ubrogepant 50-mg group, 148 of 434 (34.1%) in the ubrogepant 25-mg group, and 125 of 456 (27.4%) in the placebo group (absolute difference for 50 mg vs placebo, 11.5%; 95% CI, 5.4%-17.5%; P = .01; 25 mg vs placebo, 6.7%; 95% CI, 0.6%-12.7%; P = .07). The most common adverse events within 48 hours of any dose were nausea (50 mg, 10 of 488 [2.0%]; 25 mg, 12 of 478 [2.5%]; and placebo, 10 of 499 [2.0%]) and dizziness (50 mg, 7 of 488 [1.4%]; 25 mg, 10 of 478 [2.1%]; placebo, 8 of 499 [1.6%]). CONCLUSIONS AND RELEVANCE Among adults with migraine, acute treatment with ubrogepant compared with placebo led to significantly greater rates of pain freedom at 2 hours with 50-mg and 25-mg doses, and absence of the most bothersome migraine-associated symptom at 2 hours only with the 50-mg dose. Further research is needed to assess the effectiveness of ubrogepant against other acute treatments for migraine and to evaluate the long-term safety of ubrogepant among unselected patient populations.

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Cannabinoid 1 receptor (CB1R) inverse agonists are emerging as a potential obesity therapy. However, the physiological mechanisms by which these agents modulate human energy balance are incompletely elucidated. Here, we describe a comprehensive clinical research study of taranabant, a structurally novel acyclic CB1R inverse agonist. Positron emission tomography imaging using the selective CB1R tracer [(18)F]MK-9470 confirmed central nervous system receptor occupancy levels ( approximately 10%-40%) associated with energy balance/weight-loss effects in animals. In a 12-week weight-loss study, taranabant induced statistically significant weight loss compared to placebo in obese subjects over the entire range of evaluated doses (0.5, 2, 4, and 6 mg once per day) (p < 0.001). Taranabant treatment was associated with dose-related increased incidence of clinical adverse events, including mild to moderate gastrointestinal and psychiatric effects. Mechanism-of-action studies suggest that engagement of the CB1R by taranabant leads to weight loss by reducing food intake and increasing energy expenditure and fat oxidation.

We propose a method to estimate the regression coefficients in a competing risks model where the cause-specific hazard for the cause of interest is related to covariates through a proportional hazards relationship and when cause of failure is missing for some individuals. We use multiple imputation procedures to impute missing cause of failure, where the probability that a missing cause is the cause of interest may depend on auxiliary covariates, and combine the maximum partial likelihood estimators computed from several imputed data sets into an estimator that is consistent and asymptotically normal. A consistent estimator for the asymptotic variance is also derived. Simulation results suggest the relevance of the theory in finite samples. Results are also illustrated with data from a breast cancer study.

In randomized clinical trials, a pre-treatment measurement is often taken at baseline, and post-treatment effects are measured at several time points post-baseline, say t=1, ..., T. At the end of the trial, it is of interest to assess the treatment effect based on the mean change from baseline at the last time point T. We consider statistical methods for (i) a point estimate and 95 per cent confidence interval for the mean change from baseline at time T for each treatment group, and (ii) a p-value and 95 per cent confidence interval for the between-group difference in the mean change from baseline. The manner in which the baseline responses are used in the analysis influences both the accuracy and the efficiency of items (i) and (ii). In this paper, we will consider the ANCOVA approach with change from baseline as a dependent variable and compare that with a constrained longitudinal data analysis (cLDA) model proposed by Liang and Zeger (Sankhya: Indian J. Stat. (Ser B) 2000; 62:134-148), in which the baseline is modeled as a dependent variable in conjunction with the constraint of a common baseline mean across the treatment groups. Some drawbacks of the ANCOVA model and potential advantages of the cLDA approach are discussed and illustrated using numerical simulations.

This phase III study evaluated the efficacy and safety of cariprazine, a dopamine D3 and D2 receptor partial agonist with preferential binding to D3 receptors, in patients with acute exacerbation of schizophrenia. Patients were randomized to 6-week double-blind treatment with placebo, cariprazine 3 to 6 mg/d, or cariprazine 6 to 9 mg/d. Primary and secondary efficacy: change from baseline to week 6 in Positive and Negative Syndrome Scale total and Clinical Global Impressions-Severity scores, respectively, analyzed using a mixed-effects model for repeated measures adjusting for multiple comparisons. Safety included treatment-emergent adverse events, clinical laboratory values, vital signs, electrocardiograms, ophthalmologic examination, Columbia-Suicide Severity Rating Scale, and extrapyramidal symptom scales. In the Safety Population (placebo, n = 147; cariprazine 3-6 mg/d, n = 151; cariprazine 6-9 mg/d, n = 148), 60.5% of patients completed the study. At week 6, statistically significant least squares mean differences in favor of cariprazine versus placebo were observed for Positive and Negative Syndrome Scale total score (3-6 mg/d: -6.8, P = 0.003; 6-9 mg/d: -9.9, P < 0.001) and Clinical Global Impressions-Severity (3-6 mg/d: -0.3, P = 0.012; 6-9 mg/d: -0.5, P < 0.001). Common treatment-emergent adverse events (≥5% and twice the rate of placebo) in both cariprazine groups were akathisia, extrapyramidal disorder, and tremor; most were mild to moderate in severity. Mean changes in metabolic parameters were generally small and similar between groups. Prolactin levels decreased in all groups. In conclusion, cariprazine 3 to 6 and 6 to 9 mg/d versus placebo demonstrated significant improvement on primary and secondary efficacy parameters. Cariprazine was generally well tolerated. These results suggest that cariprazine may be a new and effective treatment for schizophrenia.