Form 8-K
8-K — Atara Biotherapeutics, Inc.
Accession: 0001193125-26-210413
Filed: 2026-05-07
Period: 2026-05-07
CIK: 0001604464
SIC: 2836 (BIOLOGICAL PRODUCTS (NO DIAGNOSTIC SUBSTANCES))
Item: Other Events
Documents
8-K — atra-20260507.htm (Primary)
EX-99.1 (atra-ex99_1.htm)
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8-K
8-K (Primary)
Filename: atra-20260507.htm · Sequence: 1
8-K
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UNITED STATES
SECURITIES AND EXCHANGE COMMISSION
WASHINGTON, D.C. 20549
FORM 8-K
CURRENT REPORT
Pursuant to Section 13 or 15(d) of the Securities Exchange Act of 1934
Date of Report (Date of earliest event reported): May 07, 2026
Atara Biotherapeutics, Inc.
(Exact name of Registrant as Specified in Its Charter)
Delaware
001-36548
46-0920988
(State or Other Jurisdiction
of Incorporation)
(Commission File Number)
(IRS Employer
Identification No.)
1280 Rancho Conejo Blvd
Thousand Oaks, California
91320
(Address of Principal Executive Offices)
(Zip Code)
Registrant’s Telephone Number, Including Area Code: (805) 623-4211
(Former Name or Former Address, if Changed Since Last Report)
Check the appropriate box below if the Form 8-K filing is intended to simultaneously satisfy the filing obligation of the registrant under any of the following provisions:
☐Written communications pursuant to Rule 425 under the Securities Act (17 CFR 230.425)
☐Soliciting material pursuant to Rule 14a-12 under the Exchange Act (17 CFR 240.14a-12)
☐Pre-commencement communications pursuant to Rule 14d-2(b) under the Exchange Act (17 CFR 240.14d-2(b))
☐Pre-commencement communications pursuant to Rule 13e-4(c) under the Exchange Act (17 CFR 240.13e-4(c))
Securities registered pursuant to Section 12(b) of the Act:
Title of each class
Trading
Symbol(s)
Name of each exchange on which registered
Common Stock, par value $0.0001 per share
ATRA
The Nasdaq Stock Market LLC
Indicate by check mark whether the registrant is an emerging growth company as defined in Rule 405 of the Securities Act of 1933 (§ 230.405 of this chapter) or Rule 12b-2 of the Securities Exchange Act of 1934 (§ 240.12b-2 of this chapter).
Emerging growth company ☐
If an emerging growth company, indicate by check mark if the registrant has elected not to use the extended transition period for complying with any new or revised financial accounting standards provided pursuant to Section 13(a) of the Exchange Act. ☐
Item 8.01 Other Events.
On May 7, 2026, Atara Biotherapeutics, Inc. (the “Company”) issued a press release titled “Atara Biotherapeutics Provides Regulatory Update on Tabelecleucel” providing an update following the Type A meeting with the U.S. Food and Drug Administration (the “FDA”) to discuss the Complete Response Letter for the EBVALLO™ Biologics License Application issued on January 9, 2026.
A copy of the press release is filed herewith as Exhibit 99.1 and is incorporated by reference into this Item 8.01.
Item 9.01 Financial Statements and Exhibits.
(d) Exhibits.
Exhibit
No.
Description
99.1
Press Release, dated May 7, 2026
104
Cover Page Interactive Data File (embedded within the Inline XBRL document)
SIGNATURES
Pursuant to the requirements of the Securities Exchange Act of 1934, the registrant has duly caused this report to be signed on its behalf by the undersigned hereunto duly authorized.
ATARA BIOTHERAPEUTICS, INC.
Date:
May 7, 2026
By:
/s/ AnhCo Thieu Nguyen
AnhCo Thieu Nguyen, Ph.D.
President and Chief Executive Officer
(Duly Authorized Officer and Principal Executive Officer)
EX-99.1
EX-99.1
Filename: atra-ex99_1.htm · Sequence: 2
EX-99.1
Exhibit 99.1
Atara Biotherapeutics Provides Regulatory Update on Tabelecleucel
THOUSAND OAKS, Calif.--(BUSINESS WIRE)-- Atara Biotherapeutics, Inc. (Nasdaq: ATRA), a leader in T-cell immunotherapy, leveraging its novel allogeneic Epstein-Barr virus (EBV) T-cell platform to develop transformative therapies for patients with cancer and autoimmune diseases, today provided an update following the recent Type A meeting with the U.S. Food and Drug Administration (FDA) to discuss the Complete Response Letter (CRL) to the Biologics License Application (BLA) for tabelecleucel (tab-cel) held by our partner Pierre Fabre Pharmaceuticals, Inc. (PFP).
PFP, with Atara’s support, had a productive meeting with the FDA and discussed a potential path forward to resubmitting the tab-cel BLA. The FDA agreed that a single arm study using an appropriate historical control applicable to the trial population, conducted in a pre-specified manner, could serve as an adequate and well controlled study and provide safety and efficacy data in support of a future marketing application of tab-cel for the proposed indication. PFP has indicated they intend to submit an updated dataset with additional patients and longer follow up from the pivotal Phase 3 single arm ALLELE study of tabelecleucel in adults and children two years of age and older with R/R EBV+ PTLD following solid organ transplant or hematopoietic cell transplant as well as supportive data, as a part of the resubmission plan being defined with the FDA.
“We are grateful to the agency for engaging in a collaborative conversation with our partners, Pierre Fabre, and us. We appreciate the FDA’s continued engagement with PFP and Atara, and we believe the Type A Meeting provided helpful alignment on the regulatory framework to resubmit,” said Cokey Nguyen, President and Chief Executive Officer of Atara. “We will continue to support Pierre Fabre as it prepares the resubmission and anticipate providing a further regulatory update in the third quarter.”
About Atara Biotherapeutics, Inc.
Atara is harnessing the natural power of the immune system to develop off-the-shelf cell therapies for difficult-to-treat cancers and autoimmune conditions that can be rapidly delivered to patients from inventory. With cutting-edge science and differentiated approach, Atara is the first company in the world to receive regulatory approval of an allogeneic T-cell immunotherapy. Our advanced and versatile T-cell platform does not require T-cell receptor or HLA gene editing and forms the basis of a diverse portfolio of investigational therapies that target EBV, the root cause of certain diseases. Atara is headquartered in Southern California. For more information, visit atarabio.com and follow @Atarabio on X and LinkedIn.
Forward-Looking Statements
This press release contains or may imply "forward-looking statements" within the meaning of Section 27A of the Securities Act of 1933 and Section 21E of the Securities Exchange Act of 1934. For example, forward-looking statements include statements regarding: (1) the development, timing and progress of tab-cel, including the timing of PFP’s resubmission of the tab-cel BLA, the potential characteristics and benefits of tab-cel; and (2) the prospect of bringing tab-cel to U.S. patients with EBV+ PTLD. Because such statements deal with future events and are based on Atara’s current expectations, they are subject to various risks and uncertainties and actual results, performance or achievements of Atara could differ materially from those described in or implied by the statements in this press release. These forward-looking statements are subject to risks and uncertainties, including, without limitation, risks and uncertainties associated with the costly and time-consuming pharmaceutical product development process and the uncertainty of clinical success; risks related to FDA’s review of tab-cel, including the risk that a resubmission of the tab-cel BLA may not address the deficiencies identified in the CRL or other issues that may be raised by the FDA on review; the fact that PFP, and not Atara, holds the tab-cel BLA and controls the timing, content and strategy of any resubmission and related FDA interactions, and Atara's ability to influence the resubmission process is limited; our ability to access capital, and the sufficiency of Atara’s cash resources and access to additional capital on favorable terms or at all; and other risks and uncertainties affecting Atara, including those discussed in Atara’s filings with the
Securities and Exchange Commission, including in the “Risk Factors” and “Management’s Discussion and Analysis of Financial Condition and Results of Operations” sections of Atara’s most recently filed periodic reports on Form 10-K and Form 10-Q and subsequent filings and in the documents incorporated by reference therein. Except as otherwise required by law, Atara disclaims any intention or obligation to update or revise any forward-looking statements, which speak only as of the date hereof, whether as a result of new information, future events or circumstances or otherwise.
Investor and Media Relations
Amber Daugherty
Sr. Director, Strategy and Operations
adaugherty@atarabio.com
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