Why is the therapeutic effect of acute antimigraine drugs delayed? A review of controlled trials and hypotheses about the delay of effect.

In randomised controlled trials (RCTs) of oral drug treatment of migraine attacks, efficacy is evaluated after 2 hours. The effect of oral naratriptan 2.5 mg with a maximum blood concentration (Tmax ) at 2 hours increases from 2 to 4 hours in RCTs. To check whether such a delayed effect is also present for other oral antimigraine drugs, we hand-searched the literature for publications on RCTs reporting efficacy. Two triptans, 3 nonsteroidal anti-inflammatory drugs (NSAIDs), a triptan combined with an NSAID and a calcitonin gene-related peptide receptor antagonist were evaluated for their therapeutic gain with determination of time to maximum effect (Emax ). Emax was compared with known Tmax from pharmacokinetic studies to estimate the delay to pain-free. The delay in therapeutic gain varied from 1-2 hours for zolmitriptan 5 mg to 7 hours for naproxen 500 mg. An increase in effect from 2 to 4 hours was observed after eletriptan 40 mg, frovatriptan 2.5 mg and lasmiditan 200 mg, and after rizatriptan 10 mg (Tmax  = 1 h) from 1 to 2 hours. This strongly indicates a general delay of effect in oral antimigraine drugs. A review of 5 possible effects of triptans on the trigemino-vascular system did not yield a simple explanation for the delay. In addition, Emax for triptans probably depends partly on the rise in plasma levels and not only on its maximum. The most likely explanation for the delay in effect is that a complex antimigraine system with more than 1 site of action is involved.

Efficacy of ADAM Zolmitriptan for the Acute Treatment of Difficult-to-Treat Migraine Headaches.

OBJECTIVE: To understand the efficacy of zolmitriptan applied with Adhesive Dermally Applied Microarray (ADAM) in treating types of migraine (those with severe headache pain, the presence of nausea, treatment ≥2 hours after migraine onset, or migraine present upon awakening) that are historically considered to be less responsive to oral medications. BACKGROUND: ADAM is an investigational system for intracutaneous drug administration. In a pivotal Phase 2b/3 study (ZOTRIP, N = 321 in the modified intention-to-treat population), ADAM zolmitriptan 3.8 mg provided superior pain freedom and freedom from patients' usual most bothersome associated symptom (MBS), compared with placebo at 2 hours post-dose. We undertook a post hoc analysis of data from the ZOTRIP trial to examine these same outcomes in subsets of patients whose migraine characteristics have been associated with poorer outcomes when treated with oral medications. METHODS: The ZOTRIP trial was a multicenter, randomized, double-blind, placebo-controlled, parallel group Phase 2b/3 study conducted at 36 sites in the United States. Presented here are post hoc subgroup analyses of patients with nausea (n = 110) or severe pain (n = 72) at baseline, those whose treatment was delayed 2 or more hours after onset (n = 75), and those who awoke with migraine (n = 80). The Cochran-Mantel-Haenszel test was used to assess whether patients in the ADAM zolmitriptan 3.8 mg group had superior treatment outcomes compared with placebo. RESULTS: In patients with nausea, 2-hour pain freedom was achieved in 44% (26/59) in the ADAM zolmitriptan 3.8 mg group and 14% (7/51) in the placebo group (P = .005) (odds ratio = 5.11, 95% CI: 1.96-13.30), and 2-hour MBS freedom was achieved in 68% (40/59) in the active treatment group and 45% (23/51) of those receiving placebo (P = .009) (odds ratio = 2.86, 95% CI: 1.28-6.43). For those with severe pain, corresponding pain-free values were 26% (10/39) and 15% (5/33) (P = .249) (odds ratio = 2.14, 95% CI: 0.60-7.62), and MBS-free values were 64% (25/39) and 42% (14/33) (P = .038) (odds ratio = 2.86, 95% CI: 1.05-7.79). Among participants who awoke with migraine, 44% (16/36) and 16% (7/44) were pain-free in the ADAM zolmitriptan 3.8 mg and placebo groups, respectively (P = .006) (odds ratio = 4.29, 95% CI: 1.50-12.31), and 72% (26/36) vs 39% (17/44) were MBS-free, respectively (P = .003) (odds ratio = 4.40, 95% CI: 1.61-12.05). In those whose treatment was delayed ≥2 hours, pain freedom in the active treatment group and placebo group were 33% (12/36) and 10% (4/39), respectively (P = .017) (odds ratio = 4.33, 95% CI: 1.24-15.10), and MBS freedom was achieved in 69% (25/36) and 41% (16/39), respectively, in the delayed treatment group (P = .014) (odds ratio = 3.37, 95% CI: 1.27-8.95). No significant effects (overall interaction P = .353) were observed in logistical regression models of treatment by subgroup interaction. CONCLUSION: Severe pain, delayed treatment, awakening with a headache, and the presence of nausea are factors that predict a poorer response to acute migraine treatment. In these post hoc analyses of subgroups of patients with each of these characteristics in the ZOTRIP trial, participants receiving ADAM zolmitriptan 3.8 mg displayed nearly uniformly better headache responses (2-hour headache freedom and 2-hour MBS freedom) compared with those who received placebo.

Discovery of SMP-304, a novel benzylpiperidine derivative with serotonin transporter inhibitory activity and 5-HT1A weak partial agonistic activity showing the antidepressant-like effect.

We report the discovery of a novel benzylpiperidine derivative with serotonin transporter (SERT) inhibitory activity and 5-HT1A receptor weak partial agonistic activity showing the antidepressant-like effect. The 3-methoxyphenyl group and the phenethyl group of compound 1, which has weak SERT binding activity, but potent 5-HT1A binding activity, were optimized, leading to compound 35 with potent and balanced dual SERT and 5-HT1A binding activity, but also potent CYP2D6 inhibitory activity. Replacement of the methoxy group in the left part of compound 35 with a larger alkoxy group, such as ethoxy, isopropoxy or methoxy-ethoxy group ameliorated CYP2D6 inhibition, giving SMP-304 as a candidate. SMP-304 with serotonin uptake inhibitory activity and 5-HT1A weak partial agonistic activity, which could work as a 5-HT1A antagonist, displayed faster onset of antidepressant-like effect than a representative SSRI paroxetine in an animal model.

The pharmacodynamic effects of combined administration of flibanserin and alcohol.

WHAT IS KNOWN AND OBJECTIVE: Flibanserin is a serotonin 5-HT1A agonist and 5-HT2A antagonist approved for the treatment of acquired, generalized hypoactive sexual desire disorder (HSDD) in premenopausal women. Because of the increased risk of hypotension- and syncope-related adverse events (AEs) observed with coadministration of flibanserin and alcohol, alcohol use is contraindicated. To provide a more comprehensive understanding of the interaction between flibanserin and alcohol, the results of a dedicated phase 1 alcohol-interaction study and a pooled analysis of phase 3 studies of premenopausal women with HSDD are presented. METHODS: In the phase 1 study, healthy participants (males [n=23] and females [n=2]) were randomly assigned to one of five sequence groups, which determined the order in which they were to receive flibanserin 100 mg or placebo, with or without ethanol 0.4 g/kg or 0.8 g/kg. Change from baseline in seated blood pressure, orthostatic vital signs, AEs and visual analogue scale sedation outcomes were examined. Blood samples were collected at baseline and for up to 4 hours after dosing to determine flibanserin area under the plasma concentration-time curve from 0 to 4 hours (AUC0-4 ). Pooled data from five phase 3 studies of patients receiving flibanserin 100 mg once daily (n=1543), or placebo (n=1905), were analysed. RESULTS: In the phase 1 study, the incidence of hypotension and syncope increased when flibanserin was coadministered with ethanol. Sedation increased 20% and 27% from baseline with flibanserin plus ethanol 0.4 g/kg and 0.8 g/kg, respectively, at 4 hours post-dose. In the pooled analysis of phase 3 studies, 58.2% and 63.6% of participants receiving flibanserin or placebo, respectively, reported baseline alcohol use. In patients receiving flibanserin, fatigue and dizziness occurred more frequently in patients with vs. without alcohol use. WHAT IS NEW AND CONCLUSION: Results from this study suggest that increased incidence of hypotension- and syncope-related events may result from a pharmacodynamic interaction between flibanserin and alcohol, although the clinical significance of these interactions in real-world populations remains unclear.

Marmoset Serotonin 5-HT1A Receptor Mapping with a Biased Agonist PET Probe 18F-F13714: Comparison with an Antagonist Tracer 18F-MPPF in Awake and Anesthetized States.

BACKGROUND: In vivo mapping by positron emission tomography of the serotonin 1A receptors has been hindered by the lack of suitable agonist positron emission tomography probes. 18F-labeled F13714 is a recently developed biased agonist positron emission tomography probe that preferentially targets subpopulations of serotonin 1A receptors in their "active state," but its brain labeling pattern in nonhuman primate has not been described. In addition, a potential confound in the translatability of PET data between nonhuman animal and human arise from the use of anesthetics that may modify the binding profiles of target receptors. METHODS: Positron emission tomography scans were conducted in a cohort of common marmosets (n=4) using the serotonin 1A receptor biased agonist radiotracer, 18F-F13714, compared with a well-characterized 18F-labeled antagonist radiotracer, 18F-MPPF. Experiments on each animal were performed under both consciousness and isoflurane-anesthesia conditions. RESULTS: 18F-F13714 binding distribution in marmosets by positron emission tomography differs markedly from that of the 18F-MPPF. Whereas 18F-MPPF showed highest binding in hippocampus and amygdala, 18F-F13714 showed highest labeling in other regions, including insular and cingulate cortex, thalamus, raphe, caudate nucleus, and putamen. The binding potential values of 18F-F13714 were about one-third of those observed with 18F-MPPF, with marked individual- and region-specific differences under isoflurane-anesthetized vs conscious conditions. CONCLUSIONS: These findings highlight the importance of investigating the brain imaging of serotonin 1A receptors using agonist probes such as 18F-F13714, which may preferentially target subpopulations of serotonin 1A receptors in specific brain regions of nonhuman primate as a biased agonist.

Randomized, multicenter trial to assess the efficacy, safety and tolerability of a single dose of a novel AMPA receptor antagonist BGG492 for the treatment of acute migraine attacks.

BACKGROUND: Glutamate is implicated in migraine pathophysiology; amino-3-hydroxy-5-methyl-4-isoxazole propionic acid (AMPA) receptor antagonists represent a potential therapeutic approach because of their anti-excitatory actions. METHODS: This randomized, double-blind, proof-of-concept study assessed the efficacy of the AMPA receptor antagonist, BGG492 (250 mg), vs placebo and sumatriptan (100 mg), in 75 subjects with acute migraine attacks. Efficacy was measured using the Patient Migraine Diary. Pharmacokinetic and safety data were collected. RESULTS: Improvement from severe/moderate to mild/no headache pain (primary response) was reported in 58%, 58%, and 54% of BGG492-treated subjects at 2, 3, and 4 hours post-dose ( P = 0.2, 0.5, and 0.5 vs placebo), respectively, compared with 68%, 84%, and 92% sumatriptan-treated subjects, and 40%, 48%, and 44% in the placebo group. Percentages of subjects with ≥ 2-point improvement in pain score from baseline at 2 hours were 29%, 40%, and 16% for BGG492, sumatriptan, and placebo, respectively. Pain-free response at 2 hours was reported for 25%, 24%, and 16% of BGG492, sumatriptan, and placebo subjects, respectively. Adverse events were reported by 80%, 56%, and 60% of BGG492, sumatriptan, and placebo subjects, respectively. CONCLUSIONS: Proof-of-concept criterion was not met (≥ 25% BGG492 subjects with a primary response vs placebo at two timepoints). BGG492 was comparable to sumatriptan in terms of pain-free response.

Theory-based analysis of clinical efficacy of triptans using receptor occupancy.

BACKGROUND: Triptans, serotonin 5-HT1B/1D receptor agonists, exert their action by targeting serotonin 5-HT1B/1D receptors, are used for treatment of migraine attack. Presently, 5 different triptans, namely sumatriptan, zolmitriptan, eletriptan, rizatriptan, and naratriptan, are marketed in Japan. In the present study, we retrospectively analyzed the relationships of clinical efficacy (headache relief) in Japanese and 5-HT1B/1D receptor occupancy (Φ1B and Φ1D). Receptor occupancies were calculated from both the pharmacokinetic and pharmacodynamic data of triptans. METHODS: To evaluate the total amount of exposure to drug, we calculated the area under the plasma concentration-time curve (AUCcp) and the areas under the time curves for Ф1B and Ф1D (AUCФ1B and AUCФ1D). Moreover, parameters expressing drug transfer and binding rates (Acp, AФ1B, AФ1D) were calculated. RESULTS: Our calculations showed that Фmax1B and Фmax1D were relatively high at 32.0-89.4% and 68.4-96.2%, respectively, suggesting that it is likely that a high occupancy is necessary to attain the clinical effect. In addition, the relationships between therapeutic effect and AUCcp, AUCΦ1B, AUCΦ1D, and Acp · AUCcp differed with each drug and administered form, whereas a significant relationship was found between the therapeutic effect and AΦ1B · AUCΦ1B or AΦ1D · AUCΦ1D that was not affected by the drug and the form of administration. CONCLUSIONS: These results suggest that receptor occupancy can be used as a parameter for a common index to evaluate the therapeutic effect. We considered that the present findings provide useful information to support the proper use of triptans.

Clinical implications for breath-powered powder sumatriptan intranasal treatment.

The acute treatment of migraine requires matching patient need to drug and formulation. In particular, nausea and vomiting, quick time to peak intensity, and the common gastroparesis of migraineurs, all call for a variety of non-oral formulations for treatment of attacks. A novel breath-powered powder sumatriptan intranasal treatment offers an improvement, at least in pharmacokinetics, over conventional liquid nasal sumatriptan spray. The device for delivery in this breath-powered nasal sumatriptan uses natural nose anatomy to close the soft palate and propel the sumatriptan high up in the nasal cavity on one side with bidirectional airflow coming out the other side. This approach has the potential to reduce adverse events and improve efficacy. Phase 3 data on this system are in press at the time of this writing and results appear promising. The clinical role for a fast acting non-oral nasal formulation will be in those for whom tablets are bound to fail, that is, in the setting of nausea and vomiting or when the time to central sensitization, allodynia, and disabling migraine is too short for the patient to respond to a tablet. This review provides a clinical perspective on the breath-powered powder sumatriptan intranasal treatment.

Improved pharmacokinetics of sumatriptan with Breath Powered™ nasal delivery of sumatriptan powder.

OBJECTIVES: The purpose of this study was to directly compare the pharmacokinetic (PK) profile of 22-mg sumatriptan powder delivered intranasally with a novel Breath Powered™ device (11 mg in each nostril) vs a 20-mg sumatriptan liquid nasal spray, a 100-mg oral tablet, and a 6-mg subcutaneous injection. BACKGROUND: A prior PK study found that low doses of sumatriptan powder delivered intranasally with a Breath Powered device were efficiently and rapidly absorbed. An early phase clinical trial with the same device and doses found excellent tolerability with high response rates and rapid onset of pain relief, approaching the benefits of injection despite significantly lower predicted drug levels. METHODS: An open-label, cross-over, comparative bioavailability study was conducted in 20 healthy subjects at a single center in the USA. Following randomization, fasted subjects received a single dose of each of the 4 treatments separated by a 7-day washout. Blood samples were taken pre-dose and serially over 14 hours post-dose for PK analysis. RESULTS: Quantitative measurement of residuals in used Breath Powered devices demonstrated that the devices delivered 8±0.9 mg (mean±standard deviation) of sumatriptan powder in each nostril (total dose 16 mg). Although the extent of systemic exposure over 14 hours was similar following Breath Powered delivery of 16-mg sumatriptan powder and 20-mg liquid nasal spray (area under the curve [AUC]0-∞ 64.9 ng*hour/mL vs 61.1 ng*hour/mL), sumatriptan powder, despite a 20% lower dose, produced 27% higher peak exposure (Cmax 20.8 ng/mL vs 16.4 ng/mL) and 61% higher exposure in the first 30 minutes compared with the nasal spray (AUC0-30 minutes 5.8 ng*hour/mL vs 3.6 ng*hour/mL). The magnitude of difference is larger on a per-milligram basis. The absorption profile following standard nasal spray demonstrated bimodal peaks, consistent with lower early followed by higher later absorptions. In contrast, the profile following Breath Powered delivery showed higher early and lower late absorptions. Relative to the 100-mg oral tablet (Cmax 70.2 ng/mL, AUC0-∞, 308.8 ng*hour/mL) and 6-mg injection (Cmax 111.6 ng/mL, AUC0-∞ 128.2 ng*hour/mL), the peak and overall exposure following Breath Powered intranasal delivery of sumatriptan powder was substantially lower. CONCLUSIONS: Breath Powered intranasal delivery of sumatriptan powder is a more efficient form of drug delivery, producing a higher peak and earlier exposure with a lower delivered dose than nasal spray and faster absorption than either nasal spray or oral administration. It also produces a significantly lower peak and total systemic exposure than oral tablet or subcutaneous injection.

A review of needle-free sumatriptan injection for rapid control of migraine.

The treatment of migraine was transformed in 1992 with the introduction of the first triptan-based therapy, subcutaneous (SC) sumatriptan. SC sumatriptan has high efficacy and a rapid onset of action compared with other available triptans and formulations presumably because of its short Tmax, high Cmax, and avoidance of enteral absorption. Because of these characteristics, SC sumatriptan is still considered the most reliably and rapidly effective self-administered medication available for acute migraine. Even so, it is relatively little used possibly in part because of patient "needle-phobia." The needle-free sumatriptan injection system (Sumavel DosePro) was developed to address this concern. Clinical trials have shown that the needle-free system is bioequivalent to needle-based injection systems, easy to use, and capable of providing rapid and effective symptom relief for many migraine episodes. Sumavel DosePro is an effective treatment for migraine and should be part of the therapeutic armamentarium, particularly in cases where a rapid onset of action is critical or where oral administration is problematic.

Intranasal zolmitriptan for the treatment of acute migraine.

OBJECTIVE: To review the pharmacokinetics, efficacy, tolerability, and patient acceptance of zolmitriptan nasal spray (NS). BACKGROUND: Gastroparesis may delay or diminish the absorption of oral triptans, and nausea or vomiting may do the same and/or make it difficult to take a tablet. Some migraineurs require or prefer faster relief than oral medications provide. Injectable triptans provide the fastest drug delivery into the bloodstream, but many patients are reluctant to use them. Nasal sprays may address some of the problems with tablets and injectables while still providing rapid absorption of drug. METHODS: Non-systematic review. RESULTS: Significant levels of zolmitriptan NS are detectable in plasma within 2-5 minutes, and the rapid absorption is due to early uptake through the nasal mucosa. In 2 randomized trials, users of zolmitriptan NS were significantly more likely than placebo recipients to be pain-free at 15 minutes post-dose, the first time point measured, and about half of patients had sustained response at 24 hours. Studies in which patients could treat a migraine of any severity have documented significant headache response or relief with zolmitriptan NS at 10 minutes. In one trial, the rate of total symptom relief was significantly better with the NS than with placebo from 30 minutes post-dose. The most common side effect of zolmitriptan NS is unusual taste. Patient satisfaction studies indicate that zolmitriptan NS is appreciated for its speed of onset, ease of use, reliability, and overall efficacy. CONCLUSIONS: Zolmitriptan NS provides onset of headache relief within 10 minutes for some patients and quickly abolishes some of the major migraine symptoms. Good candidates are migraineurs whose episodes rapidly escalate to moderate-to-severe pain and those who have morning migraine, have a quick time to vomiting, or have failed oral triptans.

Sumatriptan iontophoretic transdermal system: history, study results, and use in clinical practice.

Nausea is a common symptom of migraine, and current treatment guidelines recommend non-oral formulations for nauseated or vomiting patients. Transdermal delivery of sumatriptan, a 5-hydroxytryptamine1B1D agonist with established efficacy in patients with migraine, represents a novel approach to acute treatment. The sumatriptan iontophoretic transdermal system circumvents the gastrointestinal tract by using low-level electrical energy to transport sumatriptan across the skin. In multiple well-controlled studies, the sumatriptan transdermal system has shown that it provides consistent drug delivery with low interpatient variability, rapid relief of migraine pain and associated symptoms, and an excellent overall safety profile, with a low incidence of triptan-sensation adverse events. Patients and health care professionals who have used the sumatriptan transdermal system give it high ratings for ease of use/application. The sumatriptan transdermal system will allow a wide range of patients, especially those who experience migraine-related nausea or vomiting, to receive the benefits of migraine-specific therapy.

Vilazodone lacks proarrhythmogenic potential in healthy participants: a thorough ECG study.

OBJECTIVE: Vilazodone is a potent serotonin reuptake inhibitor and 5-HT1A receptor partial agonist approved for the treatment of major depressive disorder (MDD) in adults. The effect of clinical and supratherapeutic doses of vilazodone on cardiac repolarization was determined in healthy volunteers. METHODS: In this Phase 1, randomized, doubleblind, placebo- and active-controlled, 3-arm, parallel, single-center study, healthy subjects received placebo; moxifloxacin 400 mg; or vilazodone (sequentially escalated every 3 days) 10, 20, 40, 60, and 80 mg/day. The primary endpoint was the time-matched change from baseline in the QT interval corrected for heart rate (QTc) using an individual correction method (QTcI). RESULTS: Placebo-corrected time-matched analysis of the QTcI duration for the vilazodone treatment effect indicated that no vilazodone dose had an upper bound that approached or exceeded 10 ms, demonstrating no signal for a significant vilazodone effect on cardiac repolarization. Vilazodone had no significant effect on heart rate, PR, or QRS interval duration. The pharmacokinetic/pharmacodynamic model showed that the QTcI slope for vilazodone was not different from 0.0 and that the predicted increase from baseline in the QTc at Cmax for the highest therapeutic dose (156 ng/ml after 40 mg/day) was < 1 ms. The incidence of adverse events (AEs) was higher in the vilazodone group (57.6%) than in the moxifloxacin (37.0%) and placebo (35.6%) groups, though AEs were generally mild to moderate in severity and resulted in few discontinuations. CONCLUSIONS: Vilazodone had no significant effect on cardiac repolarization, heart rate, PR or QRS interval duration, or ECG morphology in healthy adult participants.

Harnessing Intranasal Delivery Systems of Sumatriptan for the Treatment of Migraine.

Sumatriptan (ST) is a commonly prescribed drug for treating migraine. The efficiency of several routes of ST administration has been investigated. Recently, the intranasal route with different delivery systems has gained interest owing to its fast-acting and effectiveness. The present study is aimed at reviewing the available studies on novel delivery systems for intranasal ST administration. The oral route of ST administration is common but complicated with some problems. Gastroparesis in patients with migraine may reduce the absorption and effectiveness of ST upon oral use. Furthermore, the gastrointestinal (GI) system and hepatic metabolism can alter the pharmacokinetics and clinical effects of ST. The bioavailability of conventional nasal liquids is low due to the deposition of a large fraction of the delivered dose of a drug in the nasal cavity. Several delivery systems have been utilized in a wide range of preclinical and clinical studies to enhance the bioavailability of ST. The beneficial effects of the dry nasal powder of ST (AVP-825) have been proven in clinical studies. Moreover, other delivery systems based on microemulsions, microspheres, and nanoparticles have been introduced, and their higher bioavailability and efficacy were demonstrated in preclinical studies. Based on the extant findings, harnessing novel delivery systems can improve the bioavailability of ST and enhance its effectiveness against migraine attacks. However, further clinical studies are needed to approve the safety and efficacy of employing such systems in humans.

Ex vivo evaluation of the serotonin 1A receptor partial agonist [³H]CUMI-101 in awake rats.

[³H]CUMI-101 is a 5-HT(1A) partial agonist, which has been evaluated for use as a positron emission tracer in baboon and humans. We sought to evaluate the properties of [³H]CUMI-101 ex vivo in awake rats and determine if [³H]CUMI-101 can measure changes in synaptic levels of serotonin after different challenge paradigms. [³H]CUMI-101 shows good uptake and good specific binding ratio (SBR) in frontal cortex 5.18 and in hippocampus 3.18. Binding was inhibited in a one-binding-site fashion by WAY100635 and unlabeled CUMI-101. The ex vivo B(max) of [³H]CUMI-101 in frontal cortex (98.7 fmol/mg) and hippocampus (131 fmol/kg) agree with the ex vivo B(max) of [³H]MPPF in frontal cortex (147.1 fmol/mg) and hippocampus (72.1 fmol/mg) and with in vitro values reported with 8-OH-DPAT. Challenges with citalopram, a selective serotonin reuptake inhibitor, fenfluramine, a serotonin releaser, and 4-chloro-DL-phenylalanine, a serotonin synthesis inhibitor, did not show any effect on the standardized uptake values (SUVs) in any region. Citalopram did alter SBR, but this was due to changes in cerebellar SUVs. Our results indicate that [³H]CUMI-101 is a good radioligand for imaging 5-HT(1A) high-density regions in rats; however, the results from pharmacological challenges remain inconclusive.

Design, synthesis, and pharmacological evaluation of azetedine and pyrrolidine derivatives as dual norepinephrine reuptake inhibitors and 5-HT(1A) partial agonists.

Compounds with combined norepinephrine reuptake inhibitor (NRI) and serotonin 1A (5-HT(1A)) partial agonist pharmacology may offer a new therapeutic approach for treating symptoms of neuropsychiatric disorders including ADHD, depression, and anxiety. Herein we describe the design and optimization of novel chemical matter that exhibits favorable dual NRI and 5-HT(1A) partial agonist activity. Lead compounds in this series were found to be devoid of activity at the dopamine transporter and were shown to be brain penetrant with high receptor occupancy.

Vilazodone for the treatment of depression.

OBJECTIVE: To evaluate the clinical literature on and potential clinical role of vilazodone for the treatment of major depressive disorder. DATA SOURCES: Searches were conducted on MEDLINE (1948-February 2011), Iowa Drug Information Service (1988-February 2011), EBSCO Academic Search Premier (1975-February 2011), Google Scholar (1992-February 2011), PsycINFO (1980-February 2011), and PsycARTICLES (1985-February 2011), and on general Internet search engines including Google and Bing (no lower limit-February 2011). Search terms were vilazodone, EMD 68843, depression, and major depressive disorder. Potential prior marketers of vilazodone, including Merck KGaA in Germany and Genaissance Pharmaceuticals, were contacted for any available unpublished Phase 1, Phase 2, Phase 3 studies, or preclinical information. STUDY SELECTION AND DATA EXTRACTION: All applicable full-text English-language articles, abstracts, and professional poster presentations found were evaluated and included in the review, as well as marketing and Securities and Exchange Commission filings available from the patent holders. DATA SYNTHESIS: Vilazodone is an antidepressant recently approved by the Food and Drug Administration (FDA) that is first in a new class regarding mechanism of action. It has demonstrated efficacy in the primary outcome of the Montgomery-Asberg Depression Rating Scale (MADRS) response in an 8-week pivotal Phase 3 trial. Phase 2 trials did not demonstrate efficacy for primary outcomes of the 17-item Hamilton Rating Scale for Depression but showed statistically significant improvements in select secondary outcomes such as Clinical Global Impressions severity and MADRS. Long-term efficacy data are still forthcoming. An emerging aspect to vilazodone's development has been the identification and assessment of potential genetic biomarkers associated with both therapeutic response and more serious adverse effects. Initial studies into biomarkers have been inconclusive. CONCLUSIONS: Vilazodone is a new agent recently approved by the FDA for treating major depressive disorder. Response rates seen with vilazodone are similar to those of currently available antidepressants.

Biodistribution, toxicology, and radiation dosimetry of 5-HT1A-receptor agonist positron emission tomography ligand [11C]CUMI-101.

Sprague Dawley rats (10/sex/group) were given a single intravenous (iv) dose of CUMI-101 to determine acute toxicity of CUMI-101 and radiation dosimetry estimations were conducted in baboons with [(11)C]CUMI-101. Intravenous administration of CUMI-101 did not produce overt biologically or toxicologically significant adverse effects except transient hypoactivity immediately after dose in the mid- and high-dose groups, which is not considered to be a dose-limiting toxic effect. No adverse effects were observed in the low-dose group. The no observed adverse effect level (NOAEL) is considered to be 44.05 µg/kg for a single iv dose administration in rats. The maximum tolerated dose (MTD) was estimated to be 881 µg/kg for a single iv dose administration. The Medical Internal Radiation Dose (MIRDOSE) estimates indicate the maximum permissible single-study dosage of [(11)C]CUMI-101 in humans is 52 mCi with testes and urinary bladder as the critical organ for males and females, respectively.

Preparation and evaluation of zolmitriptan submicron emulsion for rapid and effective nasal absorption in beagle dogs.

Submicron emulsion was prepared for rapid and effective nasal absorption of zolmitriptan (ZT). The different charge inducers and pH values of the formulations were evaluated to optimize the formulations. Submicron emulsion prepared by using stearylamine as positive charge inducer with pH of 5.0 was stable and most of ZT was freely dispersed in the aqueous phase of the preparation. In vitro release study demonstrated that ZT from the submicron emulsion preparation could be released as fast as that from the solution preparation. The pharmacokinetics was studied after intranasal administration of the submicron emulsion and solution preparation of ZT to beagle dogs. ZT from the submicron emulsion was absorbed much more rapidly and the absolute availability of the submicron emulsion preparation was significantly higher compared with the solution preparation. The nasal ciliotoxicity of the preparations was evaluated by using in situ toad palate model, which indicated that the submicron emulsion of ZT did not exhibit any obvious nasal ciliotoxicity. These results demonstrated that the submicron emulsion preparation of ZT was a relatively safe dosage form for rapid and effective intranasal delivery of ZT.

Population pharmacokinetic analysis of ulotaront in subjects with schizophrenia.

Ulotaront (SEP-363856) is a trace amine-associated receptor 1 agonist with 5-HT1A agonist activity in phase III development for the treatment of schizophrenia. The efficacy of ulotaront is not mediated by blockade of D2 or 5-HT2A receptors. The aim of this study was to evaluate the population pharmacokinetics (PopPKs) of ulotaront in adult subjects using pooled data from seven phase I studies, one phase II acute study, and one 6-month extension study. Single and multiple (up to 7 days) oral doses (5-150 mg/day) were studied in both healthy adult subjects (with intensive serial plasma sampling) and adult patients with schizophrenia (some with intensive and some with sparse plasma sampling). Ulotaront was well-absorbed and exhibited dose-proportionality in doses ranging from 10 to 100 mg, in mean maximum concentration, area under the concentration-time curve, and minimum concentration. Moderate interindividual variability was observed in concentration-time profiles. The estimated median time to maximal concentration was 2.8 h and the median effective half-life was 7 h, corresponding to an exposure accumulation ratio of 1.10 at steady-state with daily dosing. There was no indication of time-dependent changes in PKs after up to 12 weeks of daily dose administration. No clinically meaningful effects on ulotaront PK parameters were observed based on race, age, sex, formulation (capsule or tablet), or clinical status (healthy volunteer vs. patient with schizophrenia); body weight was the only meaningful covariate.