This study has been terminated. (Business considerations in light of slow enrollment.)Targacept put out a press release touting good results in both primary and secondary depression endpoints in July, but a closer look at that study suggests it was not very big and the drug has a ways to go before it earns back in profit the money AZ paid to get it.
Although Targacept enrolled 574 people in the study, only those who didn't respond to a different depression drug, Celexa, made it into the arm in which TC-5214 was used as an add-on therapy. More detail here.
To date, there's been only a single phase 2 trial of TC-5214 as an add-on depression treatment, that study is not published, and it only involved about 100 people taking TC-5214.To be fair, it did work in rats and mice. Targacept put the rodents through "the forced swim test in rats," "the behavioral despair test in mice," "the social interaction paradigm in rats,"and "the light/dark chamber paradigm in rats," which are all standard tests for depression in animals. Who knew?!