Conditions: Panic Disorder
Keywords: SSRI Resistant Seroquel SR Seroquel XR Panic Disorder Comorbid Panic Disorder Quetiapine SR Quetiapine XR
Allocation: RANDOMIZED | Intervention model: PARALLEL
Enrollment: 26
Healthy volunteers: no

Brief 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.

Detailed description:
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.

Arms:
arm 1: Our target daily dose for quetiapine XR was 200 mg/day. The detailed quetiapine XR dosing guidelines were as follows: 50 mg 1 tab po at HS × 3 days, then, if 50 mg tolerated, increase to 50 mg 2 tabs at HS × 4 days; at the beginning of week 2, if the last dose was tolerated increase to 50 mg 3 tabs at HS × 3 days, then, if 150 mg tolerated, increase to 4 tabs at HS; at the beginning of week 3, if no efficacy \& the 200 mg dose was well tolerated, increase to one 300 mg tab at HS-otherwise remain at 200 mg one tab at HS; at week 4 if still no improvement, \& 300 mg was tolerable, increase to 200 mg tablet 2 at HS. From the beginning of week 5 to the end of the trial, quetiapine XR doses were held. We used quetiapine XR tablets provided by Astra Zeneca (50, 200, and 300 mg designations). arm 2: Subjects received identical-appearing placebo tablets provided by Astra Zeneca (50, 200, and 300 mg designations).

Interventions: intervention 1: quetiapine XR intervention 2: placebo
Intervention descriptions: intervention 1: Subjects will receive daily dosing at night, with a flexible dosing schedule, 50-400 mg. intervention 2: Subjects will receive daily dosing at night with caplets matching the appearance of the active drug. However, caplets will not contain any active medication.

Protocol document: