•

Two Phase 3 clinical studies are underway (MATCH and ALLELE) to evaluate tab-cel™ (tabelecleucel) in patients with Epstein-Barr virus associated post-transplant lymphoproliferative disorder (EBV+ PTLD) who have failed rituximab following hematopoietic cell transplant (HCT) or solid organ transplant (SOT).

•

9 clinical sites for the MATCH and 12 for the ALLELE studies are now open for enrollment in the U.S. with additional sites expected to open in the U.S. and other geographies.

•

Continued to expand research and development, operational and commercial leadership as we advance our pipeline, leverage the potential of our technology platform and prepare for the expected tab-cel™ CMA submission in the EU and potential launch.

•

Biotech industry veteran Dietmar Berger, M.D., Ph.D., most recently a senior R&D leader at Roche/Genentech, joined Atara as Global Head of Research and Development.

•

Appointed Mina Kim as Senior Vice President and General Counsel, who has nearly 20 years of corporate legal experience.

•

Expanded commercial leadership team with the appointment of Manuela Maronati as General Manager, Europe, who brings extensive European commercial launch and operations experience in the oncology and rare disease areas.

•

Expanded T-cell immunotherapy collaboration with Memorial Sloan Kettering Cancer Center to advance next-generation CAR T technologies in oncology, autoimmune and other diseases

•

Gained access to several of MSK’s innovative enabling technologies, including a novel CAR T construct that Atara believes has physiologic T cell activation properties, as well as methods for designing CAR T immunotherapies.

•

Entered into an exclusive research collaboration for multiple targets with Michel Sadelain, M.D., Ph.D., Director, Center for Cell Engineering at MSK, to employ next-generation technologies in developing novel CAR T immunotherapies.

•

Plan to rapidly advance novel gene-edited CAR T development programs leveraging our existing off-the-shelf T-cell immunotherapy technology platform, manufacturing expertise and research and development capabilities.

•

Strengthened cash position with the completion of two underwritten public offerings in the first quarter of 2018 with net proceeds of approximately $293.3 million. Cash, cash equivalents and short-term investments as of March 31, 2018 totaled $407.3 million, which we believe enable us to expand our near-term pipeline and accelerate pre-commercial activities as well as fund our previously planned operations to mid-2020.

•

Partnered with TrakCel, an industry-leading software provider for cell and gene therapy supply chain tracking and orchestration, to develop Atara MatchMe™, the first commercial product delivery solution designed to achieve streamlined supply and delivery of an off-the-shelf, allogeneic T-cell immunotherapy.

•

Atara MatchMe™ is being designed to provide a compelling customer experience across a diverse range of treatment centers, partners, systems and geographies to ensure tab-cel™ is safely and effectively ordered and delivered, globally to patients in the minimum possible time.

•

At the 44^th Annual Meeting of the European and Marrow transplantation (EBMT) in March 2018, Atara and its collaborating investigator at the University of North Carolina at Chapel Hill presented findings from a comprehensive literature review of the mortality burden of PTLD following HCT.

•

Based on a review of studies published since 2005, the research showed that 42.5% of PTLD patients diagnosed following HCT died as a result of the disease, and in the patients who died, the median time from initial diagnosis of PTLD to death for children and adults was under 8 weeks.

•

A multinational Phase 1 clinical study to evaluate ATA188 in patients with progressive or relapsing-remitting multiple sclerosis is also underway across clinical sites in the U.S. and Australia.

•

The primary objective of the Phase 1 study is to assess the safety of ATA188 in patients followed for at least one year after the first dose. Key secondary endpoints in the study include measures of clinical improvement such as expanded disability status scale (EDSS) and annualized relapse rate (ARR), as well as MRI imaging.

•

The first interim results from the ongoing ATA188 Phase 1 study in patients with progressive MS are expected in the first half of 2019.

•

Atara plans to initiate a Phase 1/2 clinical study of tab-cel™ in combination with Merck's anti-PD-1 (programmed death receptor-1) therapy, KEYTRUDA® (pembrolizumab), in patients with

platinum-resistant or recurrent EBV-associated nasopharyngeal carcinoma (NPC) in the second half of 2018.

•

Expect to present updated tab-cel™ results in patients with EBV+ cancers in the second half of 2018.

•

Expect operations to commence at Atara T Cell Operations & Manufacturing (ATOM) facility in the second quarter of 2018, with completion to support clinical production in 2019.

•

Cash, cash equivalents and short-term investments as of March 31, 2018 totaled $407.3 million, which includes $293.3 million in net proceeds from the two underwritten public offerings completed in the first quarter of 2018.

•

The Company reported net losses of $41.4 million, or $1.05 per share, for the first quarter of 2018, as compared to $25.7 million, or $0.88 per share, for the same period in 2017.

•

Research and development expenses were $28.5 million for the first quarter of 2018, as compared to $17.5 million for the same period in 2017. The increase in the first quarter of 2018 was due to costs associated with the Company’s continuing expansion of research and development activities, including:

o

clinical trial, manufacturing and outside service costs related to the initiation of the two tab-cel™ Phase 3 clinical studies in patients with EBV+ PTLD who have failed rituximab;

o

clinical manufacturing and the initiation of the Phase 1 clinical study of allogeneic ATA188, which was initiated in October 2017;

o

higher payroll and related costs from increased headcount, and

o

an increase in allocated facilities and information technology expenses.

•

Research and development expenses include $2.9 million and $2.1 million of non-cash stock-based compensation expenses in the first quarters of 2018 and 2017, respectively.

•

General and administrative expenses were $14.0 million for the first quarter of 2018, as compared to $8.6 million for the same period in 2017. The increase in the first quarter of 2018 was primarily due to increases in payroll and related costs driven by increased headcount to support the Company’s expanding operations and higher professional services costs. General and administrative expenses include $4.1 million and $3.2 million of non-cash stock-based compensation expenses in the first quarters of 2018 and 2017, respectively.

March 31,

December 31,

2018

2017

Assets

Current assets:

Cash and cash equivalents

$       90,495

$         79,223

Short-term investments

        316,826

            86,873

Restricted cash - short-term

               194

                 194

Prepaid expenses and other current assets

            6,099

              5,900

Total current assets

        413,614

          172,190

Property and equipment, net

          58,194

            44,129

Restricted cash - long-term

            1,200

              1,200

Other assets

               100

                 260

Total assets

$     473,108

$       217,779

Liabilities and stockholders’ equity

Current liabilities:

Accounts payable

$         6,098

$           14,711

Accrued compensation

            4,312

              5,644

Accrued research and development expenses

            6,336

              4,006

Other current liabilities

            4,303

                3,265

Total current liabilities

          21,049

              27,646

Long-term liabilities

          12,875

              12,269

Total liabilities

          33,924

            39,915

Commitments and contingencies

Stockholders’ equity:

Common stock

                   4

                     3

Additional paid-in capital

        777,797

          474,662

Accumulated other comprehensive loss

             (524)

               (151)

Accumulated deficit

      (338,093)

        (296,650)

Total stockholders’ equity

        439,184

          177,864

Total liabilities and stockholders’ equity

$     473,108

$       217,779

Three Months Ended March 31,

2018

2017

Operating expenses:

Research and development

$                 28,460

$                 17,541

General and administrative

                    13,992

                      8,620

Total operating expenses

                    42,452

                    26,161

Loss from operations

                   (42,452)

                   (26,161)

Interest and other income, net

                      1,009

                         509

Loss before provision for income taxes

                   (41,443)

                   (25,652)

Provision for income taxes

                           —

                             2

Net loss

$                (41,443)

$                (25,654)

Other comprehensive loss:

Unrealized gain (loss) on available-for-sale securities

                        (373)

                           31

Comprehensive loss

$                (41,816)

$                (25,623)

Net loss per common share:

Basic and diluted net loss per common share

$                    (1.05)

$                    (0.88)

Weighted-average shares outstanding used
   to calculate basic and diluted net loss per common share

                    39,596

                    29,056