Novel Smoking Cessation Drug for Schizophrenia

Objective: This is a Proof of Concept study planned over nearly 2 years to determine the potential efficacy of a novel drug for smokers with schizophrenia. This study will assess 60 smokers with a diagnosis of either schizophrenia or schizoaffective disorder with high quit interest on their ability to quit during a week-long attempt to abstain while receiving a novel drug vs. placebo, using a within-subjects cross-over design. Research Plan: Active drug or placebo will be provided to participants in double-blind fashion. Study participation will last 6 weeks after subjects enter the study following the screening and physical exam sessions (about 8 weeks total). Participants will engage in two identical study phases, each involving visits over 3 weeks and varying only in whether active drug or placebo is administered. The 3 weeks will involve: baseline visits, dose run-up (week 2), and week 3 (for abstinence assessments). The first week of each period will be a baseline week in which they smoke normally without any medication. During week 2, subjects will begin the dose run-up of active drug or placebo, increasing over 4 days from 1 tablet of 50 mg once daily to 100 mg b.i.d. (two 50 mg tablets twice/day), which will continue through the second and third weeks. Active drug or placebo will be administered in counter-balanced order in a cross-over design. During week 3, subjects will be instructed to try to abstain on each day, i.e. Mon-Friday. Most visits will last 60 mins and involve psychiatric assessments (including psychopathology and neurological and other side effects) ratings, providing an expired breath carbon monoxide (CO) measure that assesses smoking exposure in the past 24 hrs, as well as completing brief self-report measures of craving, withdrawal, and mood. On week 3 of each phase, one visit will involve cognitive testing. On Fri of week 3, subjects will discontinue all medication and resume ad lib smoking prior to the next study period, involving the same 3-week procedure (but with the other medication condition): baseline, dose run-up, full dose administration plus abstinence assessment. Note that active medication will be taken during only one period, with placebo taken during the other period. Pill counts will be used to measure adherence. Primary and secondary dependent measures are described separately in this report. Psychopathology will be assessed using standard rating scales to evaluate psychoses and general psychopathology and severity of illness ratings, and suicide rating scales. These and clinical impressions of patients in the study will assist in monitoring for stability or worsening of psychoses or suicidal behavior and/or the need to exit patients from the study. Laboratory and EKG monitoring at the beginning and end of the study will also be part of the subject safety procedures. Patients will be offered their choice of one of the FDA approved smoking cessation agents, i.e. nicotine replacement therapy, bupropion or varenicline for a 3-month period upon completion of the study. If patients decline open-label smoking cessation participation, they will be requested to come in for one post-study visit, 14 ± 4 days later. At the first post-study visit, if there are no adverse events, their participation will end. Methods: The novel drug or placebo will be administered double-blind in counter-balanced order in a cross-over design. This is not a clinical trial that assesses long term smoking cessation but a within-subjects comparison of the short-term effects of this drug on abstinence and abstinence symptoms over a week-long period, relative to placebo. Significance: This study addresses an important question of whether the novel drug shows potential efficacy for smoking cessation, relative to placebo, in smokers with schizophrenia. This procedure could have enormous implications for accelerating the development of this medication and similar compounds to help people quit smoking by increasing the efficiency of early medication evaluation.