Atara Biotherapeutics’ Cancer Drug Might—Might!—Have Applications for MS

Bay Area company Atara Biotherapeutics is focused on immuno-oncology. Its experimental compound tabelecleucel (tab-cel) is being investigated in two cancers, Epstein-Barr virus (EBV) associated post-transplant lymphoproliferative disorder (EBV+PTLD) and nasopharyngeal carcinoma (NPC). Those two programs are in Phase III and Phase II, respectively.

Atara is also investigating other EBV-related cancers, which are at an early stage, as well as evaluating the drug and others in early-stage trials for progressive multiple sclerosis (MS). Although the immuno-oncology efforts are the primary focus, it is the MS applications that could be transformational.

Atara was founded in 2012 and named after Atara Ciechanover, who has since died from cancer. The company’s technology came out of work at Memorial Sloan Kettering and Australia’s QIMR Berghofer Medical Research Institute. It is working on off-the-shelf, allogeneic T-cells bioengineered from donors who have healthy immune function. Current immuno-oncology treatments typically are uniquely engineered for each patient, which is both expensive and time-consuming.

The company’s Tab-cell is in Phase III for EBV+PTLD after an allogeneic hematopoietic cell transplant or solid organ transplant who have failed rituximab, and a Phase I/II trial in combination with Merck’s Keytruda in patients with platinum-resistant or recurrent EBV associated NPC. It is also being evaluated in eligible patients with EBV associated hematologic and solid tumors via an ongoing multicenter expanded access protocol (EAP) clinical study.

This year could be the big year for the company. Its chief executive officer and president, Isaac Ciechanover, is leaving the company by June 30, but says 2019 could be transformative. Results of the PTLD trials may lead to a New Drug Application (NDA) submission with the U.S. Food and Drug Administration (FDA). It also has CAR-T programs in the works for blood cancers.

But one area that has industry-watchers intrigued is the potential for MS treatment. The company’s tab-cell may be effective in controlling EBV that is involved in the progression of MS.

About 2.3 million people worldwide have MS, which is treated with various drugs used to control flareups. Proteins associated with EBV increase during flareups and when the body’s T-cells are exhausted. The idea is that tab-cell might boost the T-cells and help control the disease.

The San Francisco Business Times writes, “There are skeptics. After all, the link between MS and Epstein-Barr isn’t fully defined. Researchers believe an immune system defect in controlling the virus allows B cells—a type of white blood cell—and plasma cells to accumulate in the central nervous system.”

Dietmar Berger, Atara’s global head of research and development, told the Times, “There’s clearly a difference in the pattern of (Epstein-Barr) expression in the brain. In patients with MS, you see a broader EBV infection and more EBV proteins in the active cycle of the virus.”

The company expects data from its Phase I study of ATA-188, an off-the-shelf therapy in the first half of this year. And another compound, ATA-190, an autologous therapy created from an MS patient’s own cells that are re-engineered and infused back into the patient, is expected to begin a Phase II trial in the second half of this year. The Phase I trial of ATA-190 is supported by Atara and supervised by Michael Pender at the University of Queensland in Australia and Rajiv Khanna of the QIMR. In seven patients, that Phase I trial showed improvement in symptoms as well as neurological improvement.

At the company’s fourth-quarter and full-year 2018 financial report on February 26, Ciechanover stated, “2018 was a year of pipeline expansion and strong operational execution for Atara as we advanced our T-cell immunotherapy programs across all three of our major value drivers: tab-cel, multiple sclerosis and next-generation CAR-T…. I anticipate 2019 to be another pivotal year with multiple clinical and regulatory milestones, moving Atara closer to realizing our mission of transforming the lives of patients with serious medical conditions.”