Tony W Ho

Merck, Whitehouse Station, New Jersey, United States

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Publications (37)208.47 Total impact

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    ABSTRACT: OBJECTIVE: To evaluate the safety/tolerability of rizatriptan in the long-term acute treatment of migraine in pediatric patients. BACKGROUND: Acute migraine treatment options for children are limited. A recent single-attack trial demonstrated that rizatriptan is effective in eliminating migraine headache pain in this population. We evaluated the long-term safety and efficacy of rizatriptan when used for intermittent acute treatment. METHODS: Open-label study in pediatric migraineurs ages 12-17 years. Patients weighing <40 kg received rizatriptan (orally disintegrating tablet) 5 mg, and those weighing ≥40 kg received 10 mg. Patients could treat up to 8 mild/moderate/severe migraine attacks per month for up to 12 months. One dose of study medication was allowed in a 24-hour period. RESULTS: A total of 674 patients were enrolled, and 606 patients were treated with study medication (N = 583 for 10 mg, N = 23 for 5 mg). The mean duration in the study was 292 days, and the mean number of doses of study medication taken was 20. Over the course of the study within 14 days post-any-dose, 66.0% (400) of the 606 treated patients had any adverse event, 2.3% (14) discontinued due to an adverse event, 2.6% (16) had a serious adverse event, and 23.4% (142) had a triptan-related adverse event. Of the 16 patients with serious adverse events within 14 days post-any-dose, the adverse events in 3 were considered drug-related; all 3 patient's adverse events were classified as serious only because they were associated with an overdose (use of >1 dose of study medication in a 24-hour period). The mean percentage of patient's attacks with pain freedom at 2-hours post-dose was 46.3%; this was relatively consistent over time (Months 1-3 = 43.7%, Months 4-6 = 51.9%, Months 7-9 = 49.9%, Months 10-12 = 49.5%). CONCLUSION: Rizatriptan was generally safe and well tolerated in the long-term acute treatment of migraine in pediatric patients aged 12-17 years and demonstrated a consistent treatment effect over time.
    Headache The Journal of Head and Face Pain 10/2012; · 2.94 Impact Factor
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    ABSTRACT: This study was conducted to characterize prescription refill patterns for triptans among European patients with new prescriptions of triptans. Background: Persistency with prescriptions of triptan monotherapy for migraine headache among newly prescribed users in European primary-care practices has not been well described. Using electronic medical databases in the UK (N = 3618), France (N = 2051) and Germany (N = 954), we conducted a retrospective cohort analysis to identify refill patterns over 2 years among migraineurs receiving new prescriptions of triptan monotherapy in 2006. Of all patients, >33% of migraineurs with new triptan prescriptions received ≥1 refill of their index triptan prescriptions (UK, 44.3%; France, 34.2%; Germany, 37.7%). More than 50% never received index-triptan refill prescriptions (UK, 55.7%; France, 65.8%; Germany, 63.3%). Small proportions of patients (<7.0%) switched to alternative triptans, and even fewer switched to different prescription-medication classes (UK and Germany, 2.3%; France, 4.0%). More than 48% of patients received no further prescriptions for migraine after index prescriptions (UK, 48.5%; France, 54.9%; Germany, 54.7%). After the second year, >83.0% of patients in each country had no further prescriptions for migraine medications, <14.0% remained persistent with index prescriptions, <4.0% switched to other triptans, and <3.0% switched to alternative medication classes. In migraine patients who received new prescriptions of triptan monotherapy from their primary-care physicians, poor triptan prescription refill frequency was observed in Europe. Although consistent with potential clinical challenges in migraine management, our findings should be interpreted with caution given certain inherent limitations associated with the database study design. Further research is warranted to confirm our findings and to identify reasons for, or predictors of, triptan discontinuation.
    Cephalalgia 07/2012; 32(12):875-87. · 3.49 Impact Factor
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    ABSTRACT: Treatment options for children and adolescents with migraine are limited. This study evaluated rizatriptan for the acute treatment of migraine in children and adolescents. Randomized, double-blind, placebo-controlled, parallel-group trial in migraineurs 6-17 years old with unsatisfactory response to nonsteroidal anti-inflammatory drugs or acetaminophen/paracetamol. The trial included a double-blind run-in with weight-based rizatriptan dosing (5 mg for < 40 kg, 10 mg for ≥ 40 kg). In the Stage 1 run-in, patients were randomized in a ratio of 20:1 placebo:rizatriptan and were instructed to treat within 30 minutes of a moderate/severe migraine. Patients with mild/no pain after 15 minutes of treatment (responders) took no further study medication, whereas patients with moderate/severe pain (non-responders) proceeded to take study medication in Stage 2. Non-responders who received placebo in Stage 1 were randomized 1:1 to rizatriptan:placebo, whereas non-responders who received rizatriptan in Stage 1 were allocated to placebo in Stage 2. The primary efficacy endpoint was pain freedom at 2 hours after Stage 2 dose in 12-17-year-olds. A higher proportion of 12-17-year-olds on rizatriptan had pain freedom at 2 hours compared with those on placebo: 87/284 (30.6%) versus 63/286 (22.0%), odds ratio = 1.55 [95% CI: 1.06 to 2.26], p = 0.025. Adverse events within 14 days of dose in 12-17-year-olds were similar for rizatriptan and placebo. The pattern of findings was similar in 6-17-year-olds. Rizatriptan demonstrated a statistically significant improvement over placebo in eliminating pain and was generally well tolerated in migraineurs aged 12-17 and 6-17 years. ClinicalTrials.gov NCT01001234.
    Cephalalgia 06/2012; 32(10):750-65. · 3.49 Impact Factor
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    ABSTRACT: To compare the efficacy and safety of tafluprost, a preservative-free (PF) prostaglandin analogue, with PF timolol in patients with open-angle glaucoma or ocular hypertension. Randomized, double-masked, multicenter clinical trial. After discontinuation and washout of existing ocular hypotensive treatment, patients who had intraocular pressure (IOP) ≥23 and ≤36 mm Hg in at least 1 eye at the 08:00 hour time point were randomized 1:1 to 12 weeks of treatment with either PF tafluprost 0.0015% or PF timolol 0.5%. IOP was measured 3 times during the day (08:00, 10:00, 16:00 hours) at baseline and at weeks 2, 6, and 12. It was hypothesized that PF tafluprost would be noninferior to PF timolol over 12 weeks with regard to change from baseline IOP. The trial was powered for a noninferiority margin of 1.5 mm Hg at each of the 9 time points assessed. A total of 643 patients were randomized and 618 completed (PF tafluprost = 306, PF timolol = 312). IOPs at the 3 time points assessed during the baseline visit ranged from 23.8 to 26.1 mm Hg in the PF tafluprost group and 23.5 to 26.0 mm Hg in the PF timolol group. IOPs at the 3 time points assessed during the 12-week visit ranged from 17.4 to 18.6 mm Hg for PF tafluprost and 17.9 to 18.5 mm Hg for PF timolol. At all 9 time points, the upper limits of the 2-sided 95% confidence intervals for the difference between treatments in IOP lowering were less than the prespecified noninferiority margin. Similar percentages of PF tafluprost and PF timolol patients reported ocular pain/stinging/irritation (4.4% vs 4.6%) and pruritus (2.5% vs 1.5%). The percentages of PF tafluprost and PF timolol patients reporting conjunctival hyperemia were 4.4% vs 1.2% (nominal P = .016). The IOP-lowering effect of PF tafluprost was noninferior to that of PF timolol. PF tafluprost is an efficacious and generally well-tolerated ocular hypotensive agent.
    American journal of ophthalmology 02/2012; 153(6):1187-96. · 3.83 Impact Factor
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    ABSTRACT: To evaluate the efficacy of telcagepant in patients with migraine and coronary artery disease. Calcitonin gene-related peptide receptor antagonists, such as telcagepant, may be useful for acute migraine treatment in patients with cardiovascular disease, a population for whom triptans are contraindicated. Randomized, double-blind, two-period (6 weeks per period) crossover study in patients with stable coronary artery disease and migraine. Patients were randomized 1:1 to either: (1) Period 1: telcagepant (280-mg tablet/300-mg capsule), Period 2: acetaminophen (1000-mg); or (2) Period 1: placebo for attack 1 then acetaminophen for subsequent attacks, Period 2: telcagepant. Patients could treat up to 12 migraine attacks per period to assess the tolerability of telcagepant. The primary efficacy analysis evaluated telcagepant vs placebo on 2-hour pain freedom during the first attack of Period 1. One hundred and sixty-five of the planned 400 patients were enrolled, and 114 took at least one dose of treatment. Telcagepant was not statistically different from placebo for 2-hour pain freedom (25.0% vs 18.9%, odds ratio = 1.62 [95% confidence interval: 0.62, 4.25]). The median number of attacks treated per period was 3. No cardiovascular thrombotic adverse events occurred within 14 days of dosing. The study was underpowered due to enrollment difficulties and did not demonstrate a significant efficacy difference between telcagepant and placebo for the treatment of a migraine attack in patients with stable coronary artery disease. Telcagepant was generally well tolerated for acute intermittent migraine treatment in these patients.
    Headache The Journal of Head and Face Pain 02/2012; 52(2):224-35. · 2.94 Impact Factor
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    ABSTRACT: To assess efficacy and tolerability of rizatriptan orally disintegrating tablet (ODT) for treatment of acute migraine in patients using topiramate for migraine prophylaxis. There are limited data from prospective controlled trials demonstrating the benefit of triptans in patients who experience migraine attacks while taking prophylactic medication. This was a worldwide, randomized, placebo-controlled, double-blind, multiple-attack study in adults with a >1-year history of migraine taking a stable dose of topiramate for migraine prophylaxis and experiencing ≥2 moderate/severe attacks per month. Participants treated 3 moderate/severe attacks in crossover fashion (2 with rizatriptan 10-mg ODT, 1 with placebo) following random assignment to 1 of 3 treatment sequences. The primary end point was 2-hour pain relief. Two-hour pain relief was significantly greater with rizatriptan compared with placebo (55.0% vs 17.4%, P < .001). Response rates also favored rizatriptan for sustained pain relief from 2-24 hours (32.6% vs 11.1%, P < .001), 2-hour pain freedom (36.0% vs 6.5%, P < .001), normal functional ability at 2 hours (42.2% vs 12.7%, P < .001), and overall treatment satisfaction at 24 hours (60.8% vs 33.6%, P < .001). Few participants reported adverse experiences (16 [15.8%] with rizatriptan, 3 [3.2%] with placebo); none were serious. Rizatriptan 10-mg ODT was superior to placebo at all pain end points for treatment of acute migraine in patients using topiramate for migraine prophylaxis. Rizatriptan was generally well tolerated in this population. These results are comparable with those from clinical trials in patients not using prophylaxis, suggesting that the use of topiramate does not affect the efficacy or tolerability of rizatriptan for acute migraine treatment.
    Headache The Journal of Head and Face Pain 11/2011; 52(1):57-67. · 2.94 Impact Factor
  • Tony W Ho, Marcelo Bigal
    Headache The Journal of Head and Face Pain 04/2011; 51(4):617-8. · 2.94 Impact Factor
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    ABSTRACT: To evaluate the efficacy and tolerability of telcagepant when co-administered with ibuprofen or acetaminophen for the acute treatment of migraine. Telcagepant is an oral calcitonin gene-related peptide receptor antagonist which is being evaluated for the acute treatment of migraine. Combining telcagepant with analgesics that have a different mechanism of action could produce greater efficacy. Randomized, double-blind, placebo-controlled study. Patients were randomized to treat a moderate or severe migraine headache with either telcagepant 280 mg + ibuprofen 400 mg (N = 171), telcagepant 280 mg + acetaminophen 1000 mg (N = 171), telcagepant 280 mg (N =170), or placebo (N = 171). The primary efficacy endpoint was 2-hour pain freedom. The study had approximately 88% power to detect an additive effect of at least 15 percentage points (telcagepant combination vs telcagepant monotherapy) and 48% power to detect an additive effect of at least 10 percentage points. Safety and tolerability were assessed by adverse events and laboratory tests. The percentages of patients with 2-hour pain freedom were greater in each active treatment group compared to placebo (P < .001): telcagepant + ibuprofen = 35.2%, telcagepant + acetaminophen = 38.3%, telcagepant = 31.2%, placebo = 10.9%. No significant differences were seen for either of the combination groups vs telcagepant monotherapy, but both were numerically larger than telcagepant monotherapy. All the active treatments were generally well tolerated. The percentage of patients reporting any adverse event within 48 hours was higher in the active treatment groups than placebo: telcagepant + ibuprofen = 30.3%, telcagepant + acetaminophen = 31.6%, telcagepant = 24.8%, placebo = 18.2%. The most common adverse events reported by ≥ 4 patients in one or more of the treatment groups that included telcagepant were fatigue, nausea, dizziness, somnolence, dry mouth, and tremor. The combination of telcagepant 280 mg with either ibuprofen 400 mg or acetaminophen 1000 mg did not show a statistically significant difference from telcagepant alone. Numerically greater treatment effects in the combination treatment groups over the telcagepant 280 mg monotherapy suggest that telcagepant combination treatments may merit further evaluation in studies powered to detect smaller additive benefits. (Clinicaltrials.gov; NCT00758836).
    Headache The Journal of Head and Face Pain 04/2011; 51(4):533-43. · 2.94 Impact Factor
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    ABSTRACT: This study evaluated the CGRP receptor antagonist MK-3207 for acute treatment of migraine. Multicenter, double-blind, randomized, placebo-controlled, parallel-group, two-stage adaptive study with two interim efficacy analyses to facilitate optimal dose selection. Migraine patients were initially randomized to MK-3207 2.5, 5, 10, 20, 50 and 100 mg or placebo to treat a moderate/severe migraine. One or more doses were to be discontinued based on the first interim analysis and a lower or higher dose could be added based on the second interim analysis. The primary endpoint was two-hour pain freedom. A total of 547 patients took study medication. After the first interim analysis, the two lowest MK-3207 doses (2.5, 5 mg) were identified as showing insufficient efficacy. Per the pre-specified adaptive design decision rule, only the 2.5-mg group was discontinued and the five highest doses (5, 10, 20, 50, 100 mg) were continued into the second stage. After the second interim efficacy analysis, a 200 mg dose was added due to insufficient efficacy at the top three (20, 50, 100 mg) doses. A positive dose-response trend was demonstrated when data were combined across all MK-3207 doses for two-hour pain freedom (p < .001). The pairwise difference versus placebo for two-hour pain freedom was significant for 200 mg (p < .001) and nominally significant for 100 mg and 10 mg (p < .05). The incidence of adverse events appeared comparable between active treatment groups and placebo, and did not appear to increase with increasing dose. MK-3207 was effective and generally well tolerated in the acute treatment of migraine.
    Cephalalgia 03/2011; 31(6):712-22. · 3.49 Impact Factor
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    ABSTRACT: The objective of this study was to evaluate how enrichment for responders increases assay sensitivity in an enriched enrollment randomized withdrawal (EERW) proof-of-concept (POC) study in neuropathic pain. Adults with moderate to severe peripheral neuropathic pain entered a 3- to 4-day screening period, followed by a 12-day titration to the highest tolerated dose that provided pain control (pregabalin 50-200mg t.i.d.), and then a 9-day maintenance period. Subjects were stratified as primary responders (⩾30%), secondary responders (⩾10% to <30%), or nonresponders (<10%) based on decrease in pain intensity and were randomized to placebo or pregabalin during the randomized withdrawal period. The primary endpoint was mean of average 24-h pain intensity during the last 3days of treatment period relative to the 3days before randomization. Time-to-efficacy-failure was the key secondary endpoint. Other features included not requiring discontinuation of current analgesic therapies and blinding investigators to study design elements that could contribute to non-treatment-related responses. Effect size (ES) (mean treatment difference/SD) was used to measure assay sensitivity. Pregabalin-treated subjects (n=52) had significantly less pain than those receiving placebo (n=51) (P⩽.003). Effect size of the primary endpoint was 0.72 for primary responders and decreased if secondary and nonresponders were included in the analysis. The highest ES (1.68) was demonstrated for the endpoint time-to-efficacy-failure seen in primary responders with painful diabetic neuropathy. The EERW trial design using time-to-efficacy-failure may provide a sensitive and efficient method to conduct POC studies of novel therapies in patients with neuropathic pain. Enriching a study population with patients who have achieved a 30% decrease in pain with an investigational therapy, and using time-to-efficacy-failure during the randomized withdrawal phase as the primary endpoint, can be used for a proof-of-concept study to optimize assay sensitivity and efficiently determine the analgesic potential of a new treatment for neuropathic pain.
    Pain 03/2011; 152(3):514-21. · 5.64 Impact Factor
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    ABSTRACT: To understand migraine postdrome by directly interviewing migraine patients with postdrome symptoms. To document these symptoms, as well as impacts, as a prelude to developing a postdrome migraine questionnaire. Migraine attacks are traditionally divided into 4 phases. Of these, the postdrome is the least studied, and no patient-reported outcomes to assess symptoms and impacts of this migraine phase have been published. Qualitative concept elicitation focus groups were conducted with 34 patients in 3 geographically diverse US cities to elicit the symptoms and burden of migraine postdrome. Data elicited from focus groups were coded using Atlas.ti software to facilitate identification of concepts and terminologies of migraine postdrome. A draft questionnaire was developed based on the symptoms and impacts of migraine postdrome described by patients. Cognitive debriefing interviews were conducted with 15 patients in Connecticut and Chicago to confirm content validity, relevance, and comprehension. Patients defined the onset of postdrome as when they no longer experienced the migraine pain. Postdrome was often described as "[being] or [feeling] wiped out" and "headache hangover." The symptoms most frequently reported by the patients who participated in the focus groups and included in the draft post-migraine questionnaire were: tiredness, difficulty concentrating, weakness, dizziness, lightheadedness, and decreased energy. Patients also reported decreased activity level as a result of experiencing postdrome symptoms. Postdrome symptoms were reported to impact the ability to work, to affect family interactions and social life, and to cause cognitive impairment. A preliminary questionnaire measuring severity and duration of symptoms and severity of impacts of the post-migraine experience, with an 11-point (0 to 10) response scale, was developed. This preliminary questionnaire was tested for content validity, relevance, and comprehension using cognitive debriefing interviews. All patients reported that the questionnaire was relevant to their condition. Irrelevant and redundant items such as body tension and annoyance were eliminated. Migraine postdrome is debilitating for those who experience it. Concept elicitation and cognitive debriefing research support the relevance of the items in the post-migraine questionnaire. Future research will provide evidence of the post-migraine questionnaire's psychometric properties and interpretation guidelines.
    Headache The Journal of Head and Face Pain 01/2011; 51(1):105-17. · 2.94 Impact Factor
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    ABSTRACT: The study was carried out to assess the efficacy and tolerability of rizatriptan orally disintegrating tablet (ODT) for treating acute migraine in patients who are non-responders to sumatriptan. Many migraineurs report dissatisfaction with sumatriptan efficacy. It is unclear whether sumatriptan 100 mg non-responders will respond to other triptans. This was a randomized, placebo-controlled, double-blind study in adults with >1-year history of ICHD-II (International Classification of Headache Disorders, second edition) migraine who reported that they generally do not respond to sumatriptan (≥50% unsatisfactory response). In the baseline phase, participants treated a single moderate/severe migraine attack with open-label generic sumatriptan 100 mg. Those who continued to experience moderate/severe pain at two hours post-dose were eligible to enter the double-blind treatment phase, during which participants treated three migraine attacks in crossover fashion (two with rizatriptan 10-mg ODT, one with placebo) after being randomly assigned to one of three treatment sequences (1 : 1 : 1 ratio). The primary endpoint was two-hour pain relief. A total of 102 (94%) participants treated at least one study migraine. Pain relief at two hours was significantly greater with rizatriptan compared with placebo (51% vs. 20%, p < .001). Response rates also favored rizatriptan on two-hour pain freedom (22% vs. 12%, p = .013) as well as 24-hour sustained pain relief (38% vs. 14%, p < .001) and sustained pain freedom (20% vs. 11%, p = .036). Treatment was generally well tolerated. Rizatriptan 10-mg ODT was superior to placebo at providing two-hour pain relief and two-hour pain freedom in the treatment of acute migraine in those who do not respond to sumatriptan 100 mg. Rizatriptan was generally well tolerated in this population.
    Cephalalgia 11/2010; 31(7):786-96. · 3.49 Impact Factor
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    ABSTRACT: To evaluate whether the same or different patients respond to triptans and telcagepant. Telcagepant is an oral calcitonin gene-related peptide receptor antagonist with acute antimigraine efficacy comparable to oral triptans. It is currently unknown whether migraine patients who cannot be adequately helped with triptans might benefit from treatment with telcagepant. Post-hoc analysis of data from a randomized, controlled trial of telcagepant (150 mg, 300 mg) zolmitriptan 5 mg, or placebo for a moderate/severe migraine. Responder rates were analyzed according to patients' self-reported historical triptan response (HTR): (1) good HTR (N = 660): response in 75-100% of attacks; (2) intermediate HTR (N = 248): response in 25-74% of attacks; (3) poor HTR/no use (N = 407): response in < 25% of attacks, or patient did not take triptans. A limitation of the analysis is that the last subgroup comprised mainly (91%) patients who reported that they did not take triptans, but it was not known whether these patients were triptan-naïve or had previously used triptans and stopped taking them. For zolmitriptan, 2-hour pain relief rates were higher in the good HTR subgroup (116/162, 72%) than in the intermediate (29/62, 47%) and poor/no use (44/111, 40%) HTR subgroups. The 2-hour pain relief rates were similar across HTR subgroups for telcagepant 150 mg (48-58%), 300 mg (52-58%), and placebo (26-31%). In the poor/no use HTR subgroup, more patients receiving telcagepant 300 mg (56/98, 57.1%) had 2-hour pain relief than those receiving zolmitriptan (44/111, 39.6%; odds ratio = 2.11 [95% CI: 1.20,3.71], P = .009); the percentage for telcagepant 150 mg (57/119, 47.9%) was not significantly different from zolmitriptan (odds ratio = 1.41 [95% CI: 0.82, 2.40], P = .211). This suggests that different patients may respond to triptans or telcagepant 300 mg. Caution should be exercised in interpreting the results because of the post-hoc nature of the analysis (clinical trial registry: NCT00442936).
    Headache The Journal of Head and Face Pain 11/2010; 51(1):64-72. · 2.94 Impact Factor
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    ABSTRACT: To evaluate the long-term tolerability of telcagepant for acute treatment of intermittent migraine attacks. Background.- Telcagepant is a calcitonin gene-related peptide (CGRP) receptor antagonist being investigated for the acute treatment of migraine. Migraine patients were randomized 2:1 to double-blind treatment with telcagepant 280/300 mg or rizatriptan 10 mg for an acute mild, moderate, or severe migraine. Patients could administer a second dose within 2-24 hours for nonresponse or migraine recurrence. Patients could treat up to 8 attacks per month for up to 18 months. Safety assessments included spontaneous reports of adverse events and collection of vital signs, electrocardiograms, and laboratory assessments. The primary endpoint was the percentage of patients with ≥ 1 triptan-related adverse events in the 14-day period post dose. Of 1068 patients randomized, 641 (90%) patients treated ≥ 1 attack with telcagepant and 313 (88%) treated ≥ 1 attack with rizatriptan. A total of 19,820 attacks were treated with telcagepant (mean per patient = 31) and 10,981 with rizatriptan (mean per patient = 35). Fewer triptan-related adverse events (difference: -6.2%; 95% CI -10.4, -2.6; P < .001) and drug-related adverse events (difference: -15.6%; 95% CI -22.2, -9.0) were reported for telcagepant vs rizatriptan. The most common adverse events appeared to have generally similar incidence proportions between the treatment groups. Those with an incidence > 5% in the telcagepant group were dry mouth (9.7%, rizatriptan = 13.7%), somnolence (9.2%, rizatriptan = 16.6%), dizziness (8.9%, rizatriptan = 10.2%), and nausea (9.0%, rizatriptan = 6.4%). Telcagepant was generally well tolerated when administered for the acute intermittent treatment of migraine for up to 18 months. The incidences of triptan-related and drug-related adverse events favored telcagepant over rizatriptan.
    Headache The Journal of Head and Face Pain 11/2010; 51(1):73-84. · 2.94 Impact Factor
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    ABSTRACT: To examine total migraine freedom (TMF), defined as pain freedom and absence of associated symptoms, using rizatriptan clinical trial data and to explore advantages of TMF as a single primary composite efficacy endpoint. The FDA has set a higher regulatory hurdle for registration of new migraine agents requiring both pain freedom (or relief) and absence of each associated symptom (phonophobia, photophobia, and nausea). Twelve studies representing phase III + efficacy/safety studies of rizatriptan 10 mg in adults treating migraine were included in the meta-analysis. The percentage of patients achieving TMF at 2 hours by study and combined by treatment group was summarized by treatment paradigm (early/mild pain, moderate/severe, menstrual migraine). To demonstrate the impact of the strict migraine regulatory hurdle on clinical trial design and to compare it to TMF, simulation via bootstrap sampling was used. Odds ratios (rizatriptan vs placebo, all P < .001) for TMF were 6.2 (95% CI: [4.9, 7.7]) for moderate/severe, 2.7 (95% CI: [1.8, 4.0]) for menstrual, and 3.1 (95% CI: [2.4, 4.0]) for early/mild. Most with moderate/severe migraine reported photophobia and/or phonophobia at baseline, but only half had nausea. Simulation results showed a substantial loss of power analyzing absence of pain and each symptom compared with the composite TMF endpoint across all treatment paradigms. Rizatriptan 10 mg was superior to placebo in achieving TMF at 2 hours post-dose across all treatment paradigms. Given that the majority of patients with migraine do not exhibit all 3 associated symptoms, the TMF endpoint has significant advantages vs establishing efficacy on pain and each symptom individually.
    Headache The Journal of Head and Face Pain 10/2010; 51(3):356-68. · 2.94 Impact Factor
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    ABSTRACT: Endpoints used to evaluate the efficacy of acute anti-migraine drugs do not measure the tolerability. Sustained pain-free response with no adverse events has been recommended as a composite endpoint which measures the efficacy and tolerability attributes that patients desire. The aim of this study was to evaluate new composite efficacy-plus-tolerability endpoints based on a post-hoc analysis of patient-level data from a previous randomized, placebo-controlled trial of the calcitonin gene-related peptide (CGRP) receptor antagonist, telcagepant, and zolmitriptan in the acute treatment of migraine. Endpoints were 2-24-hour sustained pain freedom and no adverse events from 0-24 hours (SPF24NAE), 2-24 hour sustained pain relief and no adverse events from 0-24 hours (SPR24NAE), pain freedom at 2 hours and no adverse events from 0-24 hours (PF2NAE), and pain relief at 2 hours and no adverse events from 0-24 hours (PR2NAE). Results: Compared with placebo, both telcagepant 300 mg and 150 mg achieved nominal superiority (p values <.05) for SPF24NAE, SPR24NAE, PF2NAE and PR2NAE. Zolmitriptan 5 mg showed nominal superiority versus placebo for SPF24NAE, SPR24NAE and PF2NAE, but not PR2NAE. Telcagepant 300 mg showed nominal superiority versus zolmitriptan for SPF24NAE, SPR24NA and PR2NAE. Composite efficacy-plus-tolerability endpoints may be useful for facilitating comparisons between treatments.
    Cephalalgia 10/2010; 31(3):296-300. · 3.49 Impact Factor
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    ABSTRACT: Over the past 300 years, the migraine field has been dominated by two main theories-the vascular theory and the central neuronal theory. The success of vasoconstrictors such as ergotamine and the triptans in treating acute migraine bolstered the vascular theory, but evidence is now emerging that vasodilatation is neither necessary nor sufficient to induce a migraine attack. Attention is now turning to the core migraine circuits in the brain, which include the trigeminal ganglia, trigeminal nucleus, medullary modulatory regions, pons, periaqueductal gray matter, hypothalamus and thalamus. Migraine triggers are likely to reflect a disturbance in overall balance of the circuits involved in the modulation of sensory activity, particularly those with relevance to the head. In this Review, we consider the evidence pointing towards a neuronal mechanism in migraine development, highlighting the role of calcitonin gene-related peptide (CGRP), which is found in small to medium-sized neurons in the trigeminal ganglion. CGRP is released during migraine attacks and can trigger migraine in patients, and CGRP receptor antagonists can abort migraine. We also examine whether other drugs, such as triptans, might exert their antimigraine effects via their actions on the neuronal circuit as opposed to the intracranial vasculature.
    Nature Reviews Neurology 10/2010; 6(10):573-82. · 15.52 Impact Factor
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    ABSTRACT: Our study was conducted to describe prescription refill patterns among patients newly treated with triptans. Although triptans are efficacious in treating migraine headache, the persistency of triptan use among newly initiated users has not been well described. From a US pharmacy claims database, we identified patients receiving new triptan monotherapy prescriptions from 2001 to 2005. Prescription refill information was gathered for two years for each patient. Persistency was defined as sustained refills of the index triptan prescription, regardless of duration between refills. Of 40,892 patients receiving a new triptan prescription, 53.8% (N = 22031) did not persistently refill their index triptan. Of these, 25.5% discontinued prescription migraine therapy, 7.4% switched to a different triptan, and 67.1% switched to a non-triptan migraine medication at the time of their first refill. Only 46.2% of patients received at least one persistent refill. Migraine patients were more likely to discontinue their triptan after their index prescription than at any other time in their prescription refill history. The majority of patients did not persistently refill triptans, but filled prescriptions for non-specific migraine therapies such as opioids and non-steroidal anti-inflammatory drugs. Reasons for triptan discontinuation warrant further investigation.
    Cephalalgia 10/2010; 31(4):488-500. · 3.49 Impact Factor
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    ABSTRACT: This study evaluated the calcitonin gene-related peptide (CGRP) receptor antagonist telcagepant (tablet formulation) for treatment of a migraine attack and across four attacks. Adults with migraine were randomized, double-blind, to telcagepant 140 mg, telcagepant 280 mg, or control treatment sequences to treat four moderate-to-severe migraine attacks. Control patients received placebo for three attacks and telcagepant 140 mg for one attack. Efficacy for the first attack (Attack 1) and consistency of efficacy over multiple attacks were assessed. For an individual patient, consistent efficacy was defined as ≥ 3 successes, and lack of consistent efficacy was defined as ≥ 2 failures, in treatment response. A total of 1677 patients treated ≥ 1 attack and 1263 treated all four attacks. Based on Attack 1 data, telcagepant 140 mg and 280 mg were significantly (p < .001) more effective than placebo for 2-hour pain freedom, 2-hour pain relief, 2-hour absence of migraine-associated symptoms (phonophobia, photophobia, nausea), and 2-24 hours sustained pain freedom. The percentage of patients with 2-hour pain freedom consistency and 2-hour pain relief consistency was significantly (p < .001) higher for both telcagepant treatment sequences versus control. Adverse events within 48 hours for telcagepant with an incidence ≥ 2% and twice that of placebo were somnolence (placebo = 2.3%, 140 mg = 5.9%, 280 mg = 5.7%) and vomiting (placebo = 1.4%, 140 mg = 1.0%, 280 mg = 2.9%). Telcagepant 140 mg and 280 mg were effective for treatment of a migraine attack and were more consistently effective than control for intermittent treatment of up to four migraine attacks. Telcagepant was generally well tolerated. (Clinicaltrials.gov; NCT00483704).
    Cephalalgia 06/2010; 30(12):1443-57. · 3.49 Impact Factor
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    ABSTRACT: The aim of this study was to compare the efficacy and tolerability of preservative-free (PF) and preservative-containing (PC) formulations of the dorzolamide/timolol fixed combination (COSOPT™) in patients with elevated intraocular pressure (IOP). A parallel, randomized, double-masked study was conducted. After a 3-week run-in on timolol, patients with ocular hypertension, as confirmed by an IOP ≥22 mmHg, were randomized 1:1 to receive PF or PC dorzolamide/timolol twice daily for 12 weeks. IOP was measured at hour 0 (drug trough) and hour 2 (drug peak) at baseline (last day of 3-week timolol run-in), and weeks 2, 6 and 12. A total of 261 patients were randomized. Mean baseline IOPs were 23.7 mmHg for both treatments at hour 0 and 21.2 mmHg for PF dorzolamide/timolol and 21.4 mmHg for PC dorzolamide/timolol at hour 2. At all study time points (trough and peak at weeks 2, 6, and 12), the difference between treatments in mean change from baseline IOP was <0.5 mmHg. The 95% confidence intervals for the estimated treatment difference (PF minus PC) in mean change from baseline IOP at week 12 was -0.86 to 0.23 mmHg for trough (primary endpoint) and -0.39 to 0.67 mmHg for peak (secondary endpoint). The most common adverse events were ocular burning/stinging, reported by 16.0% and 21.5% of patients receiving PF and PC dorzolamide/timolol respectively, and taste perversion, reported by 3.1% and 5.4% of patients receiving PF and PC dorzolamide/timolol respectively. In patients with elevated IOP, PF and PC dorzolamide/timolol were equivalent in efficacy for change in trough and peak IOP, and had generally similar tolerability.
    Albrecht von Graæes Archiv für Ophthalmologie 05/2010; 248(12):1757-64. · 1.93 Impact Factor

Publication Stats

778 Citations
208.47 Total Impact Points

Institutions

  • 2008–2012
    • Merck
      Whitehouse Station, New Jersey, United States
  • 2010
    • Mayo Foundation for Medical Education and Research
      • Department of Neurology
      Scottsdale, AZ, United States
    • Lund University
      • Department of Clinical Sciences
      Lund, Skane, Sweden
  • 2009
    • Albert Einstein College of Medicine
      • Department of Neuroradiology
      New York City, NY, United States