No stranger to headwinds, bluebird runs into two PDUFA delays unrelated to new safety issues
Bluebird bio hit another speed bump Tuesday in its efforts to win its first FDA approvals as regulators pushed back two PDUFA dates.
The FDA delayed the action dates for beti-cel and eli-cel, the one-time gene therapies for beta-thalassemia and cerebral adrenoleukodystrophy, by three months each, the biotech said in a press release Tuesday morning. Originally scheduled for May and June, respectively, the new PDUFA dates were pushed back to August and September.
According to bluebird, the delays are not the result of any new safety events, but rather “to allow time to review additional clinical information previously submitted by the company in response to FDA information requests as part of its ongoing reviews.” The company also said the delays won’t affect the priority review status for either program or prevent it from earning priority review vouchers should either be greenlighted.
Shares of bluebird $BLUE fell a modest 4% as the market opened Tuesday.
Analysts saw the lack of new safety issues as a small win, given how such concerns always have the gene therapy field on guard. Mani Foroohar of SVB Leerink wrote to investors Tuesday morning safety continues to be “a critical issue — as BLUE looks to extend its cash runway with sale of priority review vouchers upon BLA approvals.”
Foroohar added that much remains up in the air, as bluebird is planning to give further updates in its full-year report next month. Additionally, the FDA had planned to hold an adcomm for beti-cel in March, where the full breadth of any safety issues will likely be discussed in detail. The adcomm will still take place but will also be delayed to align with the new PDUFA dates, and a new date has not been set.
Whatever the reason for Tuesday’s news, the delays mark yet another potential roadblock in bluebird’s long-running quest to get its gene therapies approved in the US.
Last February, bluebird voluntarily paused two studies for its sickle cell gene therapy after two patients unexpectedly developed cancer and a cancer-like case, resulting in a four-month clinical hold. Bluebird later demonstrated that the cancer case was unrelated to the viruses used in its gene therapy and that the cancer-like case was a misdiagnosis. But the pause resulted in a delayed launch for beti-cel, which uses the same lentiviral delivery method, in Europe.
Then, in August, another cancer-like case popped up in a trial for eli-cel, forcing bluebird to hit the brakes on the study. That case, bluebird said, did appear linked to the gene therapy. In the same announcement, bluebird said it would stop selling its gene therapies in Europe after failing to reach pricing agreements with governments.
Observers speculated bluebird did not want to charge less for the drug, branded Zynteglo in Europe, for fear it would ultimately have to lower prices in the US. In Germany, the only country for which bluebird has disclosed details, authorities offered $790,000 for the one-time treatment, with the payout moving to $950,000 if the therapy was still working after five years. But bluebird wanted something in the range of $1.8 million after that time period.
The biotech instead shifted its focus to a US approval and completed its split into two companies, ostensibly driven by the repeated delays in its gene therapy programs. Bluebird submitted its application late last year and was granted priority review in November for beti-cel and December for eli-cel.
Should bluebird win approval for one of the programs, it would become the third gene therapy to enter the US market after Spark’s Luxturna and Novartis’ Zolgensma and the first-ever FDA approved ex vivo gene therapy.
Clarification: This article has been updated to clarify the timing of the scheduled adcomm for beti-cel. Previously slated for March, the adcomm will be delayed and does not have a new date set as of Tuesday, Jan. 18.