NEW YORK – Atara Biotherapeutics last week said the US Food and Drug Administration has issued a complete response to its biologics license application (BLA) seeking approval for Ebvallo (tabelecleucel) as a treatment for Epstein-Barr virus (EBV)-positive posttransplant lymphoproliferative disease (PTLD).
Thousand Oaks, California-based Atara submitted the BLA in July 2024, seeking approval for Ebvallo as a treatment for patients 2 years and older who have received one prior therapy for EBV-positive PTLD after hematopoietic stem-cell or solid organ transplant.
The FDA in the complete response letter said it couldn't approve Ebvallo, an EBV-specific T-cell immunotherapy, due to findings at a third-party manufacturing facility during a standard pre-license inspection. According to Atara, the agency didn't cite any manufacturing deficiencies or note any clinical efficacy or safety issues in the data that it submitted as part of its BLA, and the FDA didn't ask it to submit any new clinical trial data.
In its BLA, Atara submitted data from several studies, including from the pivotal Phase III ALLELE trial, in which Ebvallo demonstrated a 48.8 percent objective response rate. Ebvallo received marketing authorization from the European Commission in December 2022 as a treatment for EBV-positive PTLD, which arises when the EBV virus infects lymphoid cells and causes uncontrolled proliferation, which, in turn, can become cancerous.
"We are working closely with our partner Pierre Fabre Laboratories, the FDA, and the third-party manufacturer to address the feedback to support marketing approval for Ebvallo," Atara President and CEO Cokey Nguyen said in a statement. According to Atara, the European Medicines Agency has approved a second third-party manufacturer, Fujifilm Diosynth Biotechnologies, which has a facility in Thousand Oaks and will play a critical role in supplying Ebvallo globally.
The FDA had granted priority review to Atara's original BLA, putting it on a six-month review clock. Nguyen noted that once the third-party manufacturer addresses its good manufacturing practices compliance issues, Atara will resubmit its BLA and expects a positive approval decision from the FDA within six months.
Once Ebvallo achieves FDA approval, Atara will be eligible to receive a $60 million milestone payment from partner Pierre Fabre, as well as double-digit tiered royalties as a percentage of net sales, and milestones related to commercial sales of the treatment. Until then, steering Ebvallo through the FDA regulatory process will require capital. Atara said it has entered into a nonbinding agreement with Redmile Group for a $15 million equity line of credit, which it believes will fund activities required to achieve BLA approval.
Atara said that it is also working with an unnamed financial adviser to explore strategic opportunities for its CAR T assets and that this adviser is exploring "a wider range of additional strategic alternatives," including an acquisition, merger, reverse merger, and asset sale, as well as other business combinations and transactions. "Through this process, Atara is already in active discussions with several potential parties," the company said, adding that whether Atara pursues any deals will ultimately depend on the terms.
If a deal is not reached that provides Atara funds to advance its CAR T-cell development programs, the company said it will suspend all CAR T activities and significantly limit its spending to only those supporting Ebvallo's US market approval, including transferring all operational activities related to the treatment to Pierre Fabre.
In addition to the equity line of credit it secured from Redmile Group, Atara said it is exploring alternative financing options, including non-dilutive sources of capital. At the end of 2024, the company had $43 million in cash, cash equivalents, and short-term investments.