The Economic Burden of Chromosome Translocations and the Benefits of Enhanced Screening for Cattle Breeding.

The cattle breeding industry, through both of its derivatives (dairy and beef), provides 81% of milk and 22% of meat required globally. If a breeding bull is sub-fertile, this impacts herd conception and birth rates, and it is generally accepted that having a proactive genetic screening programme can prevent further losses. Chromosome translocations are the leading genetic cause of infertility in livestock and, in cattle, this extends beyond the classical 1:29 to other Robertsonian translocations (RobTs) and to reciprocal translocations (RECTs). The incidence of both (collectively termed RTs) varies between breeds and herds; however, we estimate that RECTs are, most likely, at least twice as common as RobTs. The purpose of this study was to develop an industry economic model to estimate the financial impact of an RT event at the herd level. If we assume a conservative incidence rate of 0.4% for Rob1:29 with each one impacting the conception rate by 5%, we calculate that actively screening for and removing a Rob1:29 bull could benefit an impacted herd by GBP 2.3 million (approx. USD 2.8 million) over six years. A recently updated screening protocol developed in our lab for all RTs, however (with a projected combined incidence of 1.2%, impacting conception rates by 10%), could benefit an impacted herd by GBP 7.2 million (nearly USD 9 million) for each RT found. For an industry worth USD 827.4 billion (dairy) and USD 467.7 billion (beef), expanding knowledge on incidence and further dissection of the potential costs (financial and environmental) from RTs is essential to prevent further losses.

Assessment of the Abuse Potential of the Orexin Receptor Antagonist, Suvorexant, Compared With Zolpidem in a Randomized Crossover Study.

Suvorexant is a dual orexin receptor antagonist approved in the United States and Japan for the treatment of insomnia at a maximum dose of 20 mg. This randomized double-blind crossover study evaluated the abuse potential of suvorexant in 36 healthy recreational polydrug users with a history of sedative and psychedelic drug use. Single doses of suvorexant (40, 80, and 150 mg: 2-7.5 × maximum dose), zolpidem (15 and 30 mg: 1.5-3 × maximum dose), and placebo were administered, with a 10-day washout between treatments. Subjective and objective measures, including visual analog scales (VASs), Addiction Research Center Inventory, and cognitive/psychomotor tests, were evaluated for 24-hour postdose. Suvorexant had significantly greater peak effects on "drug liking" VAS (primary endpoint) than placebo. Although effects of suvorexant on abuse potential measures were generally similar to zolpidem, they remained constant across doses, whereas zolpidem often had greater effects at higher doses. Suvorexant (all doses) had significantly fewer effects than zolpidem 30 mg on secondary measures, such as "high" VAS, Bowdle VAS, and Addiction Research Center Inventory morphine-benzedrine group. The overall incidence of abuse-related adverse events, such as euphoric mood and hallucination, was numerically lower with suvorexant than zolpidem. In agreement with its classification as a schedule IV drug, suvorexant demonstrated abuse potential, compared with placebo. The abuse potential was similar to zolpidem using certain measures, but with a reduced incidence of abuse-related adverse events. Although this suggests that the overall abuse liability of suvorexant may be lower than zolpidem, the actual abuse rates will be assessed with the postmarketing experience.

Pharmacokinetics of digoxin in healthy subjects receiving taranabant, a novel cannabinoid-1 receptor inverse agonist.

INTRODUCTION: Interaction studies with digoxin (Lanoxin; GlaxoSmithKline, Research Triangle Park, NC, USA), a commonly prescribed cardiac glycoside with a narrow therapeutic index and a long half-life, are typically required during the development of a new drug, particularly when it is likely that digoxin may be given to patients also treated with the new agent, taranabant--a cannabinoid-1 receptor inverse agonist--for weight loss. This study was designed to establish if this combination of therapy has the potential of a significant pharmacokinetic interaction. METHODS: This open-label, fixed-sequence, two-period study investigated whether taranabant, administered to steady state, affects the well-described single-dose pharmacokinetics of digoxin. During the first period, 12 healthy men and women ranging in age from 21 to 35 years received a single oral dose of digoxin 0.5 mg. Following a 10-day wash out, they started a 19-day taranabant dosing regimen (6 mg once daily from day -14 to day 5) designed to establish and maintain steady-state levels of taranabant. On study day 1, subjects received a single oral dose of digoxin 0.5 mg. The plasma levels of digoxin were followed for an additional 4 days while the dosing of taranabant continued. RESULTS: The geometric mean ratio and 90% confidence intervals for digoxin AUC(0-infinity) were 0.91 (0.83, 0.99), falling within the prespecified comparability intervals (CI) of (0.8, 1.25), which is within the usually allowed interval for bioequivalence. The geometric mean ratio and 90% CI for digoxin maximum plasma concentration (C(max)) were 1.23 (1.09, 1.40). The median time to C(max) was the same for both treatments. CONCLUSION: Multiple doses of 6 mg taranabant do not have a clinically meaningful effect on the pharmacokinetics of a single oral dose of digoxin.