bluebird bio, Inc. BLUE announced that the FDA has granted Breakthrough Therapy designation to Lenti-D for the treatment of patients with cerebral adrenoleukodystrophy (CALD). We note that the Breakthrough Therapy designation expedites the development and review of drugs intended as a standalone therapy or in combination with one or more other drugs, to treat a serious or life-threatening disease when preliminary data suggest that the drug may demonstrate substantial improvement over existing therapies on one or more clinically significant endpoints.The designation is supported by positive preliminary data from the ongoing phase II/III Starbeam Study (ALD-102) evaluating Lenti-D investigational gene therapy in boys with CALD, 17 years of age or less who do not have a matched sibling donor. The two-year study has assessed the safety and efficacy of this investigational gene therapy. CALD is a hereditary neurological disorder.We note that Lenti-D investigational gene therapy enjoys orphan drug status in the Unites States and Europe. The drug was also granted Rare Pediatric Disease designation by the FDA for the treatment of adrenoleukodystrophy (ALD).Per the FDA’s Rare Pediatric Disease Priority Review Voucher program, a sponsor who receives a marketing application approval for a rare pediatric indication is generally eligible for a Priority Review Voucher, which can be redeemed to obtain Priority Review for a subsequent marketing application for a different product.bluebird bio has built a diverse pipeline with its lentiviral-based gene therapies, T cell immunotherapy expertise and gene editing capabilities. bluebird bio’s gene therapy clinical programs include Lenti-D for the treatment of cerebral adrenoleukodystrophy, and LentiGlobin for the treatment of transfusion-dependent β-thalassemia, also known as β-thalassemia major, and severe sickle cell disease.The oncology pipeline primarily focuses on developing novel T cell-based immunotherapies, including chimeric antigen receptor (CAR T) and T cell receptor (TCR) therapies. The lead oncology programs include bb2121 and bb21217. Both these are anti-BCMA CAR T programs which the company is developing in partnership with Celgene CELG.CAR T therapies are in focus since 2017 with the approval of Gilead’s GILD Yescarta and Novartis’ NVS Kymriah. In the past six months, bluebird’s stock has returned 12.9% against a 8.7% decline registered by the industry.Zacks Rankbluebird carries a Zacks Rank #3 (Hold). You can see the complete list of today’s Zacks #1 Rank (Strong Buy) stocks here.Wall Street’s Next AmazonZacks EVP Kevin Matras believes this familiar stock has only just begun its climb to become one of the greatest investments of all time. It’s a once-in-a-generation opportunity to invest in pure genius.Click for details >>Want the latest recommendations from Zacks Investment Research? Today, you can download 7 Best Stocks for the Next 30 Days. Click to get this free report Novartis AG (NVS): Free Stock Analysis Report Gilead Sciences, Inc. (GILD): Free Stock Analysis Report Celgene Corporation (CELG): Free Stock Analysis Report bluebird bio, Inc. (BLUE): Free Stock Analysis Report To read this article on Zacks.com click here. Zacks Investment Research