Editor's note: Bluebird shares were surging 54% to $26.15 in mid-day trading after Bluebird bio sold 5.9 million shares at $17 in an initial public offering Tuesday after markets had closed in New York. CAMBRIDGE, Mass. ( TheStreet) -- There has been a rush to the biotech IPO window including both Bluebird bio ( BLUE) and Agios Pharmaceuticals ( AGIO). What makes these new companies a little different from other public biotech debuts is the lack of significant (or any) clinical data. While this is not unprecedented -- Verastem ( VSTM) went public in 2012 with only preclinical data on hand -- the relatively early stage of these biotech IPOs raises the risk level for investors. A closer examination of Bluebird highlights both the risks and potential rewards of such early-stage biotech IPOs. Bluebird is a gene therapy company that uses a lentiviral vector to ex vivo deliver functional genes into a patient's hematopoietic stem cells. Sangamo BioSciences ( SGMO) is probably the closest publicly traded company working on a similar therapeutic approach to Bluebird. Sangamo uses its zinc finger proteins for gene regulation and/or modification. Bluebird is focusing on monogenic diseases and has programs in childhood cerebral adrenoleukodystrophy (CCALD), beta-thalassemia, sickle cell disease (SCD) and chimeric antigen receptors T-cells (CAR T.) While this is certainly a robust pipeline for a small-cap drug company, these programs are all essentially still in the preclinical phase, meaning no testing on actual patients has begun. Bluebird did run what they called a phase I trial in CCALD but this was simply a non-interventional natural history study. In other words, no patients were actually treated with a drug but they followed patients to assess the natural course of the disease. These data were then used to generate endpoints that could be used to demonstrate efficacy and safety in an interventional study. Given the rarity of the CCALD, this was actually a very useful approach but it certainly does not provide any evidence to demonstrate the efficacy of Bluebird's drug. The money raised by Bluebird IPO will allow the company to move their Lenti-D product into a phase II/III clinical trial in CCALD, which will be the first time the drug will be dosed in humans. Bluebird does have human dosing of a precursor drug to their LentiGlobin product for the treatment of beta-thalassemia major, where their collaborators in France treated six patients. While the efficacy was encouraging, one of the six patients showed the insertion of the functional gene into the HMGA2 gene and this lead to fears of a pre-leukemic event. While the inserted genes were there for two to three years, there appeared to be no negative consequences.