Atara Biotherapeutics Presents Initial ATA188 Phase 1 Safety Results for Patients with Progressive Multiple Sclerosis at the 5th Congress of the European Academy of Neurology (EAN)

SOUTH SAN FRANCISCO, Calif., June 29, 2019 (GLOBE NEWSWIRE) -- Atara Biotherapeutics, Inc. (Nasdaq: ATRA), a leading off-the-shelf, allogeneic T-cell immunotherapy company developing novel treatments for patients with cancer, autoimmune and viral diseases, today announced initial ATA188 Phase 1 safety results for patients with progressive multiple sclerosis (MS) at the 5th Congress of the European Academy of Neurology (EAN) in Oslo, Norway. ATA188, Atara’s off-the-shelf, allogeneic T-cell immunotherapy, targets specific Epstein-Barr virus (EBV) antigens believed to play an important role in the pathogenesis of MS.

The primary objective of Atara’s ongoing ATA188 Phase 1, dose-escalating clinical study is to evaluate safety and tolerability for patients with progressive MS. Initial safety results as of April 8, 2019, showed that the first three ATA188 dose cohorts were well tolerated with no dose-limiting toxicities and no ≥3 grade treatment-related, treatment-emergent adverse events. The study is continuing with the objective of identifying a recommended Phase 2 dose (RP2D). In addition, a randomized, double-blind, placebo-controlled Phase 1b extension period for this study using the RP2D is now planned following completion of the open-label, dose-escalation period.

“We are encouraged by the initial ATA188 safety and tolerability results from the first three cohorts,” said AJ Joshi, M.D., Senior Vice President and Chief Medical Officer of Atara Biotherapeutics. “We continue to enroll patients with progressive MS in the fourth and final planned dose escalation cohort and look forward to presenting preliminary efficacy results from the initial cohorts of this study at a scientific congress in the second half of 2019.”

Key secondary endpoints of the Phase 1 study include measures of clinical improvement such as expanded disability status scale (EDSS) and MRI imaging as well as other clinical activity measures. The study is expected to enroll a total of 24-30 primary and secondary progressive MS (PPMS, SPMS) patients in the U.S. and Australia.  For more information about the study, please visit ClinicalTrials.gov (NCT03283826).

Details of the presentation are as follows:

EPO2229: Preliminary phase 1 safety of ATA188, a pre-manufactured, unrelated donor (off-the-shelf, allogeneic) Epstein-Barr virus (EBV)-targeted T-cell immunotherapy for patients with progressive multiple sclerosis (MS)
Poster Presentation Date and Time: Sunday, June 30, 2019, 12:30 - 1:15 p.m. CEST
Session Title: MS and related disorders 6
Location: Screen B12 in the Poster Area in the Exhibition Hall
Authors: Michael P. Pender1, Suzanne Hodgkinson2, Simon Broadley3, John W. Lindsey4, Zara A. Ioannides1, Blake T. Aftab5, Daniel Munson5, Kevin Rasor5, Farahnaz Forozan5, Philippe Foubert5, Laurence Gamelin5, Amy Feng5, Jonathan Willmer5
Affiliations: 1. Faculty of Medicine, The University of Queensland, Brisbane, Australia. 2. South Western Sydney Clinical School, University of New South Wales, Sydney, Australia. 3. School of Medicine, Griffith University, Southport, Australia. 4. Department of Neurology, McGovern Medical School, University of Texas Health Science Center, Houston, USA. 5. Atara Biotherapeutics, South San Francisco, USA

About Multiple Sclerosis
Multiple Sclerosis (MS) is a chronic neurological autoimmune disease that affects more than two million people around the world. Relapsing-remitting MS (RRMS) is the most common form of MS and is characterized by episodes of new or worsening signs or symptoms (relapses) followed by periods of recovery. Progressive MS (PMS) is a severe form of the disease for which there are few therapeutic options. There are two categories of PMS, both of which are characterized by persistent progression and worsening of MS symptoms and physical disability over time. Primary Progressive MS (PPMS) occurs when continuous progressive disease is present at diagnosis and has been reported to occur in approximately 15% of newly diagnosed cases of MS.  Secondary Progressive MS (SPMS) initially begins as RRMS and develops into a progressive form. Treatment history indicates that approximately 80% of people with RRMS will eventually develop SPMS. There is substantial unmet medical need for new and effective therapies for patients with PPMS and SPMS. Most treatment options that work well in reducing flares in RRMS have not been shown to be effective in slowing or reversing disability in PMS. Scientific and clinical findings support a biologic connection between Epstein-Barr Virus (EBV) and MS.

About off-the-shelf, allogeneic ATA188 and autologous ATA190
ATA188 and ATA190 are immunotherapies that use T Cells to target Epstein-Barr Virus (EBV) antigens believed to be important for the potential treatment of multiple sclerosis (MS). Both candidates selectively target EBV-positive cells; however, ATA188 is off-the-shelf and allogeneic, whereas ATA 190 is autologous. ATA188 and ATA190 utilize T-cell immunotherapy technology pioneered by Professor Rajiv Khanna at QIMR Berghofer. Atara is advancing an ongoing Phase 1 off-the-shelf, allogeneic ATA188 study in patients with progressive MS across clinical sites in the U.S. and Australia and plans to initiate a randomized autologous ATA190 study in progressive MS patients.

About Atara Biotherapeutics, Inc.
Atara Biotherapeutics, Inc. (@Atarabio) is a leading off-the-shelf, allogeneic T-cell immunotherapy company developing novel treatments for patients with cancer, autoimmune and viral diseases. Atara’s technology platform leverages research collaborations with leading academic institutions with the Company’s scientific, clinical, regulatory and manufacturing expertise. Atara’s pipeline includes tab-cel® (tabelecleucel), which is in Phase 3 development for patients with Epstein-Barr virus-associated post-transplant lymphoproliferative disorder (EBV+ PTLD) as well as in earlier stage development for other EBV-associated hematologic malignancies and solid tumors, including nasopharyngeal carcinoma (NPC); T-cell immunotherapies targeting EBV antigens believed to be important for the potential treatment of multiple sclerosis; and next-generation chimeric antigen receptor T-cell (CAR T) immunotherapies. The company was founded in 2012 and is co-located in South San Francisco and Southern California. Our Southern California hub is anchored by the state-of-the-art Atara T-cell Operations and Manufacturing (ATOM) facility in Thousand Oaks, California. For additional information about the company, please visit atarabio.com.

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: the results from Atara’s ongoing ATA188 Phase 1 clinical study; the continuation of this study and identification of a recommended Phase 2 dose; the initiation of a randomized, double-blind, placebo-controlled portion of this study; and Atara’s expectation of presenting preliminary efficacy results from this study at a scientific congress in the second half of 2019. These forward-looking statements are subject to risks and uncertainties, including those discussed in Atara Biotherapeutics' filings with the Securities and Exchange Commission (SEC), including in the “Risk Factors” and “Management’s Discussion and Analysis of Financial Condition and Results of Operations” sections of the Company’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 Biotherapeutics 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 & MEDIA CONTACTS:

Investors:
John Craighead, Atara Biotherapeutics
650-410-3012
jcraighead@atarabio.com

John Grimaldi, Burns McClellan
212-213-0006 x362
jgrimaldi@burnsmc.com

Media:
Nancie Steinberg, Burns McClellan
212-213-0006 x318
nsteinberg@burnsmc.com

Atara-Bio1_logo_300x300 (003).png

Source: Atara Biotherapeutics, Inc.