“The hope that Lenti-D may benefit boys facing such a devastating disease inspires all of us at bluebird,” said David Davidson, M.D., chief medical officer, bluebird bio.
“Having this proportion of the initial cohort of patients meet the primary endpoint is truly gratifying, bringing us one step closer to our goal of making Lenti-D available for patients with CALD. The two patients who did not meet the primary endpoint underscore the devastating nature of CALD, the importance of early diagnosis through newborn screening, and the challenges of the current standard of care with allogeneic hematopoietic stem cell transplant (HSCT).
“Patient 2016 had not experienced an MFD, but withdrew from the study due to radiographic progression of disease and underwent an allogeneic HSCT. He subsequently died from complications of the allogeneic transplantation. Patient 2018, as previously reported in April 2016, had rapid disease progression beginning early in his participation in the study, resulting in a neurological function score (NFS) of 5.
“The rapidity of his disease progression suggests it would have been difficult to alter his early neurological decline given that transplant takes months to exert a therapeutic effect in CALD. Our hearts go out to these two boys and their families. Our program would not be possible without our brave patients and their families, and we are tremendously grateful for their participation.”
As of June 13, 2017, 17 patients with CALD have completed 2 years of follow-up post-Lenti-D treatment, with 15/17 (88%) remaining free of major functional disabilities (MFDs), the primary endpoint of the trial. This exceeds the pre-defined interim efficacy benchmark for the study of MFD-free survival of 76%, derived from the literature and based on clinical data from an earlier observational study describing that natural history of CALD and outcomes from allogeneic HSCT.
In the Starbeam Study, the safety profile of Lenti-D was consistent with myeloablative conditioning. No patients treated with Lenti-D had graft versus host disease (GvHD), and there was no graft rejection or clonal dominance.
In December 2016, bluebird bio announced that the Starbeam study had been expanded to treat eight additional patients at sites in Europe and the US, and the study is currently enrolling the additional patients.
The expansion of the study is intended to enable the first manufacture of Lenti-D in Europe, the subsequent treatment of subjects in Europe, and to bolster the overall clinical data package for potential future regulatory filings in the United States and Europe.