Acute nonarteritic anterior ischemic optic neuropathy and exposure to phosphodiesterase type 5 inhibitors.

INTRODUCTION: Nonarteritic anterior ischemic optic neuropathy (NAION), a rare visual disorder, has been reported in men using phosphodiesterase type 5 inhibitors (PDE5i) for erectile dysfunction. AIM: We examined whether intermittent use of PDE5i is associated with acute NAION onset within approximately five half-lives following drug ingestion. METHODS: One hundred two ophthalmology centers in the United States and Europe identified potential cases of NAION. An expert adjudication committee conducted a blind review of the records of those with recent PDE5i use to classify cases as Definite, Possible, or not NAION. Subjects provided information on PDEi use via telephone interview. Each NAION case's PDE5i exposure immediately prior to onset was compared against his recent patterns of use in an observational case-crossover design. A sample size of 40 cases with intermittent PDE5i exposure in the 30 days prior to NAION onset was needed to detect an odds ratio (OR) of 3.0 with 80% power. MAIN OUTCOME MEASURES: The daily relative risk for acute NAION on days within five half-lives of PDE5i use vs. other days was estimated via an OR obtained from conditional logistic regression. RESULTS: Among 43 Definite NAION cases with PDE5i exposure in the prior 30 days, the OR was 2.15 (95% confidence interval [CI]: 1.06, 4.34). When 21 Possible NAION cases were included (n = 64), the OR was 2.36 (95% CI: 1.33, 4.19). CONCLUSIONS: We found an approximately twofold increased risk of acute NAION within five half-lives of PDE5i use compared with use in a more prior time period. Bias from inaccurate recall of exposure was unlikely to have substantially affected the results. Based on our results, we estimate that weekly use of PDE5i adds three NAION cases per 100,000 men 50 years and older annually.

Randomized, double-blind, crossover trial of sildenafil in men with mild to moderate erectile dysfunction: efficacy at 8 and 12 hours postdose.

OBJECTIVES: To clarify the period of responsiveness to sildenafil. METHODS: Under a double-blind protocol, men with mild to moderate erectile dysfunction (International Index of Erectile Function [IIEF] Erectile Function domain score, 11 to 25) were randomized to sildenafil (100 mg) or placebo and attempted intercourse 8 hours (range, 7 to 9 hours) postdose (first 4-week phase) and 12 hours (11 to 13 hours) postdose (second 4-week phase after treatment crossover). The primary outcome was the per-patient proportion (PPP; least squares means [95% confidence interval]) of affirmative responses to the Sexual Encounter Profile question 3 (SEP3: "Did your erection last long enough for you to have successful intercourse?"). RESULTS: For sildenafil (n = 174) versus placebo (n = 177), baseline values were similar but the PPP of successful intercourse attempts increased to 76% (69% to 82%) versus 50% (43% to 57%) in phase 1 (odds ratio [OR] = 3.2) and 79% (72% to 85%) versus 52% (44% to 60%) in phase 2 (OR = 3.5), and the PPP of Erection Hardness Score 4 erections (completely hard and fully rigid) was 41% (34% to 48%) versus 10% (7% to 15%) in phase 1 (OR = 6.2) and 44% (37% to 51%) versus 17% (12% to 23%) in phase 2 (OR = 4.0). Thus, at 12 hours, the odds of successful intercourse tripled and of a completely hard erection quadrupled. The sildenafil group achieved greater (P <0.001) PPP of successful penetration (SEP2), satisfaction with erection hardness (SEP4), and satisfaction with the sexual experience (SEP5); improvement in IIEF domain scores; and treatment satisfaction on the Erectile Dysfunction Inventory of Treatment Satisfaction. CONCLUSIONS: In men with mild to moderate ED, responsiveness to sildenafil may persist much longer than 4 hours.

Pharmacokinetics of an extended release formulation of alprazolam (Xanax XR) in healthy normal adolescent and adult volunteers.

The purpose of this study was to estimate pharmacokinetics, safety, and tolerability of single doses of an extended release formulation of alprazolam (Xanax XR) in adolescent and adult healthy volunteers. This was a randomized, open-label, single-dose, 2-period crossover study. Twelve adolescent healthy volunteers (13-17 years) and 12 adult healthy volunteers (20-45 years) received single doses of Xanax XR 1 mg or 3 mg tablets. Blood samples were obtained predose and for 48 hours postdose. Plasma samples were assayed for alprazolam and its two active metabolites alpha-hydroxy-alprazolam and 4-hydroxy-alprazolam using a validated LC-MS/MS method. Safety assessments included clinical laboratory tests, vital signs, and adverse event monitoring. At both dose levels, mean plasma concentration-time profiles of alprazolam, alpha-hydroxy-alprazolam, and 4-hydroxy-alprazolam were similar in adolescent and adult subjects. The ratios of estimated geometric means for AUC(0-infinity) and Cmax between adolescents and adults for both dose levels were 115% (95% CI: [93, 143]) and 111% (95% CI: [95, 129]), respectively. An assessment of dose proportionality between the 3 mg and 1 mg alprazolam doses within both age groups indicated that the AUC(0-infinity) and Cmax were both within 80-125% equivalence limits. Parent-metabolite ratios were similar in both age groups and were consistent with those previously reported. Alprazolam was well tolerated by both age groups. The most common adverse event was somnolence, which occurred in a dose-related manner. Based on the similar pharmacokinetic profiles, dosing of Xanax XR should be similar in adolescents and adults.

Treatment benefit and the risk of suicidality in multicenter, randomized, controlled trials of sertraline in children and adolescents.

OBJECTIVE: The aim of this study was to examine the balance between the benefits of treatment and the risk of suicidality in children and adolescents in multicenter, randomized, controlled trials of sertraline versus placebo. METHOD: The published literature was searched for multicenter, randomized, placebo-controlled trials of sertraline for pediatric mental disorders. Four trials were identified: Two (pooled) in pediatric major depressive disorder (MDD; Wagner 2003) and two in obsessive-compulsive disorder (OCD; March et al. 1998; POTS Team 2004). Using intent-to-treat (ITT) analysis populations, the authors calculated the number needed to treat (NNT) for response and remission and the number needed to harm (NNH) for suicidality, and their ratio, for each clinical trial. RESULTS: NNTs ranged from 2 to 10, indicating clinically meaningful benefits. Benefit was greater for OCD than for MDD, and for adolescents as compared with children in MDD. No age effect was apparent for OCD. Suicidality was reported in 8 patients (5 assigned to sertraline and 3 assigned to placebo). All but 1 (a placebo-treated patient in the Pfizer OCD trial) were enrolled in the sertraline MDD trial. The NNH for suicidality in MDD was 64. Treatment emergent suicidality was more common in children (NNH 28.7) than in adolescents (NNH 706.3). Because no patient developed suicidality in sertraline-treated OCD patients, the NNH for sertraline in OCD approaches infinity. CONCLUSIONS: With the stipulation that doctor and patient preferences necessarily play a critical role in the choice of treatment, NNT to NNH ratios indicate a positive benefit-to-risk ratio for sertraline in adolescents with MDD and in patients of all ages with OCD.

The Role of High-Potency Benzodiazepines in the Treatment of Panic Disorder.

Medication plays a central role in the treatment of panic disorder, with the goal of eliminating panic attacks and restoring normal function (i.e., achieving full remission). Four drug classes have similar efficacy (tricyclic antidepressants, selective serotonin reuptake inhibitors [SSRIs], benzodiazepines, and monoamine oxidase inhibitors). Nonetheless, benzodiazepines remain the most prescribed medication for panic disorder in the United States. The high-potency benzodiaze-pines alprazolam (available as immediate- and extended-release tablets) and clonazepam (available as tablets and orally disintegrating wafers) are the only benzodiazepines approved by the U.S. Food and Drug Administration for the treatment of panic disorder. High-potency benzodiaze-pines, with their proven efficacy in panic disorder exerted through control of the central nervous system excitability by a selective and potent enhancement of inhibitory gamma-aminobutyric acid-mediated neurotransmission, are also a safe and well-tolerated option for potentiation of rapid treatment response when initiating treatment with SSRIs. Judicious use of high-potency benzodiazepines followed by a cautious taper and discontinuation may optimize the benefits and minimize any potential risk associated with this class of drugs.

Treatment of pediatric anxiety disorders: an open-label extension of the research units on pediatric psychopharmacology anxiety study.

BACKGROUND: An 8-week placebo-controlled study, the Research Units on Pediatric Psychopharmacology Anxiety Study, documented beneficial effects of fluvoxamine in the treatment of pediatric social anxiety, separation anxiety, or generalized anxiety disorders. Following completion of this study, participants were invited to enter a 6-month open-label treatment phase designed to examine three issues: (a) long-term maintenance of response in fluvoxamine responders, (b) acute response to fluoxetine in fluvoxamine nonresponders, and (c) acute response to fluvoxamine in placebo nonresponders. METHODS: Participants aged 6-17 years meeting criteria for social anxiety, separation anxiety, or generalized anxiety disorders previously treated in an 8-week placebo-controlled trial (n = 128) were offered open treatment. Changes in symptoms of anxiety during open treatment were assessed in three groups: (a) fluvoxamine responders maintained on fluvoxamine, (b) fluvoxamine nonresponders changed to fluoxetine, and (c) placebo nonresponders changed to fluvoxamine. Response was defined based on Clinical Global Impression criteria. RESULTS: During 6 months of continued open treatment, anxiety symptoms remained low in 33 of 35 (94%) subjects who initially responded to fluvoxamine. Among 14 fluvoxamine nonresponders switched to fluoxetine, anxiety symptoms appeared significantly improved in 10 (71%) subjects. Finally, among 48 placebo nonresponders, 27 (56%) showed clinically significant improvement in anxiety on fluvoxamine. CONCLUSION: The current findings concerning extended treatment of pediatric anxiety disorders are only preliminary, because treatment was uncontrolled. Results suggest that an initial fluvoxamine response is likely to be retained with continued treatment, that some fluvoxamine nonresponders may respond to fluoxetine, and that some placebo nonresponders may respond to fluvoxamine.