a study of quetiapine sr (seroquel sr) to treat ssri-resistant, comorbid panic disorder patients

Conditions: Panic Disorder

Summary: the primary objective of this study is to test the hypothesis that a ssri plus quetiapine sr (seroquel sr) will result in superior early (first 1-3 weeks of treatment) stabilization of panic symptoms in ssri-resistant, comorbid panic disorder patients versus a ssri plus placebo.

this was a single-site, double-blind, placebo-controlled (plac), randomized, parallel group (2 groups), 8-week, quetiapine extended release (xr) coadministration trial. ssri resistance was determined either historically or prospectively. patients were randomized if they remained moderately ill (cgi-s score ≥ 4). change in the pdss scale total score was the primary efficacy outcome measure. responders were identified as those with a ≥50 % decrease from their baseline pdss score. in the early weeks of therapy, xr was flexibly and gradually titrated from 50 to 400 mg/day. conclusions: this proof-of-concept rct did not support the efficacy of this treatment strategy for ssri-resistant pd. quetiapine xr was generally well-tolerated. important limitations were the small sample size, and the relatively low average dose of quetiapine xr used.

Eligibility criteria:
inclusion criteria: * provision of written informed consent * diagnosis of panic disorder by dsm-iv tr and confirmed by mini plus interview * females and males ages 18-65 years old * female patients of childbearing potential must by using a reliable method of contraception and have a negative urine human chorionic gonadotropin (hcg) test at enrollment * able to understand and comply with the requirements of the study * have a cgi illness severity score = or \> 4 * patients with comorbid major depression, dysthymia or other anxiety problems are eligible to participate as well. exclusion criteria: * pregnancy or lactation * any dsm-iv tr axis i disorder not mentioned in the inclusion requirements * suicidal or danger to self or others * known intolerance to quetiapine fumarate or intolerance to ssri therapy * use of any of the following cytochrome p450 3a4 inhibitors in the 14 days preceding enrollment including but not limited to : ketoconazole, itraconazole, fluconazole, erythromycin, clarithromycin, troleandomycin, indinavir, nelfinavir, ritonavir, fluvoxamine and saquinavir * use of any of the following cytochrome p450 inducers in the 14 days preceding enrollment including but not limited to : phenytoin, carbamazepine, barbiturates, rifampin, st. john's wort, and glucocorticoids * administration of a depot antipsychotic injection within one dosing interval (for the depot) before randomization * substance or alcohol dependence at enrollment (except dependence in full remission, and except for caffeine or nicotine dependence), as defined by dsm-iv criteria * opiates, amphetamine, barbiturate, cocaine, cannabis, or hallucinogen abuse by dsm-iv tr criteria within 4 weeks prior to enrollment * medical conditions that would affect absorption, distribution, metabolism, or excretion of study treatment * unstable or inadequately treated medical illness (e.g. angina pectoris, hypertension) as judged by the investigator * involvement in the planning and conduct of the study * previous enrollment or randomization of treatment in the present study * participation in another drug trial within 4 weeks prior enrollment into this study or longer in accordance with local requirements * a patient with a diagnosis of type i or type ii diabetes mellitus (dm) * an absolute neutrophil count (anc) of 1.5 x 109 per liter * a lifetime history of a pre-existing cns/neurological disorder e.g. epilepsy, tbi, brain tumor * patient with severe personality disorders * patients who have started a new course of psychotherapy (cbt, supportive, insight-oriented) within 1 month of the screening visit * patients unwilling to refrain from participation in psychotherapy during the 9-week period of the study.

Keywords: ssri resistant seroquel sr seroquel xr panic disorder comorbid panic disorder quetiapine sr quetiapine xr