Anxiety in Recovering Opiate Dependence

This is a 16 week study of the efficacy of quetiapine in treating symptoms of generalized anxiety disorder (GAD) in subjects with comorbid opiate dependence. The study will be conducted in a prospective, randomized, double-blind, and placebo-controlled fashion. Study subjects will be inpatients at a residential drug-treatment facility, enrolled in a 1 year methadone-to-abstinence treatment plan. Subjects will be randomized to receive either quetiapine or placebo in addition to ongoing drug addiction treatment. Subjects will be followed for 16 weeks and a variety of psychometric assessments will be made.

Hypothesis One: Compared to placebo, Quetiapine will demonstrate a greater reduction in symptoms of anxiety in subjects with GAD and remitted comorbid opiate abuse.

Exploratory Hypotheses: Compared to placebo, Quetiapine will demonstrate a greater improvement in psychosocial functioning and compliance with community norms in subjects enrolled in a residential drug addiction treatment facility.


Eligibility Criteria:
Inclusion Criteria:

* Provision of written informed consent
* A diagnosis of opiate dependence as defined by Diagnostic and Statistical Manual of Mental Disorders- Fourth Edition (DSM-IV) during the past two years.
* A diagnosis of generalized anxiety disorder as defined by Diagnostic and Statistical Manual of Mental Disorders- Fourth Edition (DSM-IV) within the past 6 months.
* Males and females aged 21-55 years
* Female patients of childbearing potential must be 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
* Subjects must be free of illicit drug use for the past 3 months
* Subjects must have received methadone maintenance therapy for at least 3 months, and have been at least 2 weeks methadone-free
* Good health, as assessed by medical history, physical examination and laboratory tests

Exclusion Criteria:

* Pregnancy or lactation
* Current diagnosis of any Axis I disorder other than GAD, substance dependence in remission, or nicotine dependence
* Patients who, in the opinion of the investigator, pose an imminent risk of suicide or a danger to self or others
* Known intolerance or lack of response to quetiapine fumarate, as judged by the investigator
* Use of any of the following cytochrome P450 3A4 inhibitors in the 14 days preceding enrolment 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 randomisation
* Medical conditions that would affect absorption, distribution, metabolism, or excretion of study treatment
* Unstable or inadequately treated medical illness (e.g. diabetes, angina pectoris, hypertension) as judged by the investigator
* Involvement in the planning and conduct of the study
* Previous enrollment or randomisation 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 Diabetes Mellitus (DM) fulfilling one of the following criteria:
* Unstable DM defined as enrollment glycosylated hemoglobin (HbA1c) \>8.5%.
* Admitted to hospital for treatment of DM or DM related illness in past 12 weeks.
* Not under physician care for DM
* Physician responsible for patient's DM care has not indicated that patient's DM is controlled.
* Physician responsible for patient's DM care has not approved patient's participation in the study
* Has not been on the same dose of oral hypoglycaemic drug(s) and/or diet for the 4 weeks prior to randomization. For thiazolidinediones (glitazones) this period should not be less than 8 weeks.
* Taking insulin whose daily dose on one occasion in the past 4 weeks has been more than 10% above or below their mean dose in the preceding 4 weeks Note: If a diabetic patient meets one of these criteria, the patient is to be excluded even if the treating physician believes that the patient is stable and can participate in the study.
* An absolute neutrophil count (ANC) of 1.5 x 109 per liter
* Positive urine drug screening test for drugs of abuse