Atara Therapeutics’ Ebvallo, already marketed in Europe for a transplant-related blood cancer, will not hit the U.S. market just yet, forcing the company to “significantly reduce expenses.”
The FDA Thrusday issued a Complete Response Letter to immunotherapy-focused Atara Therapeutics for its T cell therapy for transplant complications, marketed in Europe as Ebvallo, sending the company’s stock plummeting by more than 40%.
The company stressed that the regulatory rejection was not based on safety concerns about the therapy itself, but from a pre-licensing inspection of a third-manufacturing facility that turned up problems. The company offered no further details on the nature of the FDA’s concerns.
In their statement, Atara announced that unless the company can secure more funding, they intend to “significantly reduce company expenses” to only those needed to get Ebvallo approved, or even transferring Ebvallo-related activities to its partner, French pharmaceutical Pierre Fabre. If Ebvallo receives FDA approval, Atara is eligible to receive a $60 million milestone payout from Pierre Fabre.
Ebvallo received market authorization in the European Union in December 2022 and in the U.K. in 2023 to treat patients receiving an organ- or a bone marrow-transplantation who develop a blood cancer called Epstein-Barr virus positive post-transplant lymphoproliferative disease (PTLD). These are patients who are taking immunosuppressive drugs post-transplant and develop a rare condition where the presence of the common Epstein-Barr virus causes immune cells to rapidly grow out of control. While the risk of developing PTLD is generally low, it can vary depending on the type of transplant, up to as high as 32% for small intestine transplant recipients.
Ebvallo is an allogenic T cell therapy that targets immune cells infected by Epstein-Barr virus. A Phase III trial found a 48.8% response rate in patients who had already received some other form of treatment.
There are no currently approved treatments for PTLD, though the antibody rituximab has been used off-label in the past, as have certain kinds of chemotherapy.
