Study: NCT00129467

Intervention type: DRUG
Group type: EXPERIMENTAL
Intervention: Methylphenidate
Description: Subjects will take methylphenidate 5 mg twice daily (bid) for 3 days, then 10 mg bid for the remainder of the study. Should a subject have a 50% decrease in their depressive symptoms as measured by the Montgomery Asberg Depression Rating Scale (MADRS) at the initial dose of methylphenidate, they will be maintained at that lower dose as long as their MADRS score remains reduced by 50%. During the 18-day blinded treatment period the total daily dose will not exceed 20 mg.~If subjects have side effects when increasing to 10 mg bid, they will drop back to 5 mg bid. If the participant develops psychosis or cardiac events, they will be discontinued from methylphenidate.~Subjects who receive methylphenidate and respond with a 50% reduction in MADRS score will have the option to continue in the open label portion of the study for up to 6 weeks. For patients taking methylphenidate 10 mg bid whose MADRS score is \> 10 at day 18, the dose may be increased to 15 mg bid.

Intervention type: DRUG
Group type: PLACEBO_COMPARATOR
Intervention: Placebo
Description: Subjects assigned to placebo will receive 1 capsule of placebo twice per day (bid) for 3 days and then 2 capsules bid for the remainder of the study. Should a subject have a 50% decrease in their depressive symptoms as measured by the Montgomery Asberg Depression Rating Scale (MADRS) at the initial dose of placebo, they will be maintained at that lower dose as long as their MADRS score remains reduced by 50%.~If subjects have side effects when increasing the dose to 2 capsules bid, they will drop back to 1 capsule bid. If the participant develops psychosis or cardiac events, they will be discontinued from the intervention.

Intervention type: DRUG
Group type: PLACEBO_COMPARATOR
Intervention: Selective Serotonin Uptake Inhibitor (SSRI)
Description: Each subject will be treated with a SSRI. Patients who are taking an SSRI at the time of enrollment will continue on the same medication during the 18-day blind treatment period. The prescribed dose will only be adjusted if it is more than the highest dose in the recommended range (fluoxetine to 40 mg, paroxetine to 40 mg, citalopram to 40 mg, sertraline to 150 mg). Patients who are not on a SSRI at the time of enrollment will be prescribed citalopram 10 mg per day for 2 weeks, then 20 mg per day.~A subject's SSRI may be discontinued if the subject experiences moderate to severe side effects likely attributable to a SSRI. If subjects experience similar symptoms when increasing their citalopram dose to 20 mg per day, they will drop back to 10 mg per day. During the open label extension, the SSRI may be increased, decreased, or changed to a different SSRI or other antidepressant with the exception of venlafaxine and bupropion

Intervention type: DRUG
Group type: EXPERIMENTAL
Intervention: Selective Serotonin Uptake Inhibitor (SSRI)
Description: Each subject will be treated with a SSRI. Patients who are taking an SSRI at the time of enrollment will continue on the same medication during the 18-day blind treatment period. The prescribed dose will only be adjusted if it is more than the highest dose in the recommended range (fluoxetine to 40 mg, paroxetine to 40 mg, citalopram to 40 mg, sertraline to 150 mg). Patients who are not on a SSRI at the time of enrollment will be prescribed citalopram 10 mg per day for 2 weeks, then 20 mg per day.~A subject's SSRI may be discontinued if the subject experiences moderate to severe side effects likely attributable to a SSRI. If subjects experience similar symptoms when increasing their citalopram dose to 20 mg per day, they will drop back to 10 mg per day. During the open label extension, the SSRI may be increased, decreased, or changed to a different SSRI or other antidepressant with the exception of venlafaxine and bupropion