This biotech stock was recently upgraded to ‘Outperform’ by Evercore ISI Group: In-Line. Analysts expect triple-digit growth for this company over the next five years.
bluebird bio, Inc. (BLUE)
from Canaccord Genuity Research
bluebird bio, Inc. (BLUE) provided an interim update at EHA on the ongoing HGB-206 Phase 1 severe sickle cell disease trial for LentiGlobin. The first patient of the Group C with 6 months of follow-up showed normal total hemoglobin level of 14.2 g/dL while generating over 60% antisickling HbAT87Q.
This is very encouraging since Group C patients were treated under the amended study protocol with refined Drug Product (DP) manufacturing process and received LentiGlobin gene therapy made from stem cells collected from peripheral blood after mobilization with plerixafor, thus validating the modified manufacturing process and the use of peripheral blood stem cell as product base.
Other Group C patients are also showing strong hemoglobin generation Four patients in Group C with 3 months of follow-up demonstrated to have ≥30% antisickling HbAT87Q generation (3 – 6 g/dL) of the average total hemoglobin level of ~11 g/dL. We are interested in seeing if the same group of patients show an increase in not just the absolute hemoglobin count but also in the HbAT87Q fraction by 6-month follow-up, as previously seen in Group B (n = 2) where the average HbAT87Q faction increased from ~26% to ~38% for 3- and 6-month follow-up.
Preliminary data suggests time to clinical benefit may be driven by CD34+ cell concentration. We noted that Group C patients’ drug products were based on peripheral blood stem cell, whereas Group B used bone marrow stem cells. When comparing Group C and Group B patients, we noticed that Group C patients showed similar level of drug product vector copy number (VCN, 4.0 for Group C and 3.1 for Group B) and peripheral blood VCN, and % transduced cells (~81% for Group C and ~87% for Group B). Furthermore, it is interesting that 4 of the Group C patients with 3-month follow-up achieved similar HbAT87Q faction and hemoglobin count (39% HbAT87Q & 10.8 g/dL total Hb) to that of Group B by 6-month follow-up (38% HbAT87Q & 11.5 g/dL total Hb). This could be due to the higher CD34+ concentration for Group C drug product (7.1 x 106 CD34+ cells/kg) than that of Group B (2.7 x 106 CD34+ cells/kg). While we do acknowledge that Group B has a limited patient sample number, we do see the preliminary data suggesting that the concentration of CD34+ cells may be a key driver of time to clinical benefit.
We maintain our BUY rating on BLUE with a $250 PT given our continued positive expectation for the active programs. The EHA update provided us with greater confidence in the new product manufacturing process to increase vector count numbers for the LentiGlobin platform. We look to further update from the LentiGlobin program to see if the Group C patients would show increase in HbAT87Q faction over time, which would greatly increase LentiGlobin’s clinical value proposition.
John Newman, Ph.D. and David Huang, Canaccord Genuity Research, www.canaccordgenuity.com, June 18, 2018