Orlando, FL 3/20/12 (StreetBeat) -- A drug called TC-5214 being developed by Winston-Salem biotech firm Targacept ( Nasdaq: TRGT ) and pharmaceutical giant AstraZeneca ( NYSE: AZN ), has failed to show enough positive effect as a treatment for major depressive disorder and will be shelved for now, according to an announcement from Targacept. The failure in two newly completed Phase 3 clinical trials is disappointing but not entirely unexpected, since the same drug had also come up short in two previous Phase 3 studies in November and December. TC-5214 had shown much more promise as a adjunct treatment for depression in earlier Phase 2 trials. The latest trials gave patients either TC-5214 or a placebo. The announcement said both groups showed about 40 percent improvement on a scale that measures depression severity, meaning the new drug didn’t have any measurable clinical effect. That being the case, Targacept and AstraZeneca won’t be pursuing a New Drug Application with the FDA for TC-5214 related to major depressive disorder, said Targacept CEO Don deBethizy. He said the earlier Phase 3 results prompted Targacept to carefully evaluate its business, and he said the company will announce further plans by the end of April. “Targacept has built a deep and mechanistically diverse clinical pipeline, and, with multiple [drug candidates] in Phase 2 development in areas of large medical need and commercial opportunity and over $225 million in cash, we are well positioned for future success,” he said. Targacept shares took a big price hit when the earlier Phase 3 failures were announced, falling from near $20 per share last fall to a recent low of $5.31 in January. They closed at $7.41 on Monday, prior to the announcement of the latest trial failures. StreetBeat Disclaimer Distributed by Viestly