Weekly Formulation of Fluoxetine for Newly Treated Patients with Depression Gary S. Kabinoff, 1 John M. Plewes 2 and Michael G. Wilson 3 1 Martin Memorial Medical Center, Stuart, Florida, USA 2 Lilly Research Laboratories, Indianapolis, Indiana, USA 3 College of Pharmacy and Health Sciences, Butler University, Indianapolis, Indiana, USA SHORT COMMUNICATION Clin Drug Invest 2002; 22 (6): 403-405 1173-2563/02/0006-0403/$25.00/0 © Adis International Limited. All rights reserved. Successful pharmacological resolution of depressive symptoms requires adequacies in the dosage and duration of antidepressant therapy, [1] but these have been seriously less than optimal for many patients with major depressive disorder (MDD). [2] A significant reason for the lack of suc- cess in therapy is non-compliance. [3] Montgomery et al. [4] postulated that once-weekly drug adminis- tration might improve compliance because the burden on patients to remember to take their med- ication is substantially reduced and drug adminis- tration is more convenient. The selective serotonin reuptake inhibitor (SSRI) fluoxetine is the only agent capable of providing an antidepressant effect when administered less frequently than daily because both the parent compound and its desmethylated metabolite norfluoxetine have long elimination half-lives. [5] Furthermore, a new for- mulation of enteric-coated fluoxetine has been shown to be well tolerated, effective [6] and associ- ated with excellent compliance [7] when adminis- tered once weekly to patients who had previously responded to fluoxetine 20mg daily for short-term treatment of MDD. This enteric-coated formula- tion has been approved by regulatory agencies in North and South America and Europe for continu- ation treatment of MDD. In a naturalistic study, Buongiorno et al. [8] reported that enteric-coated fluoxetine administered at higher dosages (90 to 540mg) once weekly was effective and well toler- ated in the short-term maintenance treatment of MDD, and was also effective in the seven patients who had begun treatment de novo. Therefore, patients with depression who have not been pre- viously treated may also benefit from this regimen. Our objective was to examine the efficacy and tolerability of weekly administration of enteric- coated fluoxetine in treatment-naïve patients with depression seen in our clinic in the Southeastern United States. Patients and Methods We retrospectively identified all consecutive outpatients with a confirmed diagnosis of clinical and treatment-naïve depression who had been seen in our clinic and naturalistic environment from 18 May to 15 November 2001, and had been prescribed weekly treatment with enteric-coated fluoxetine. The 12 patients identified included eight women and four men whose ages ranged from 17 to 71 years. Ten patients had at least one medical or psychiatric comorbid diagnosis and seven of those patients were receiving concomitant medication. The severity of depressive symptoms was evaluated at baseline and again at each patient’s monthly visit to provide an indication of progress. We used the total of the 17-Item Hamilton Depres- sion Rating Scale (HAMD 17 ) as a measure of severity of depressive symptoms. In this cohort, depression severity was classified as mild (HAMD 17 total score = 10 to 13), moderate