Atara Biotherapeutics Inc. (NASDAQ:ATRA) Reports Phase 1a ATA188 Data With Progressive Multiple Sclerosis Patients Showing SDI

Atara Biotherapeutics Inc. (NASDAQ:ATRA) has announced the presentation of results from the first part of its current Phase 1 ATA188 study in treating progressive forms of multiple sclerosis. ATA188 is the company’s allogeneic EBV-specific off-the-shelf T-cell immunotherapy.

ATA188 demonstrates sustained disability improvement in patients

Data from the study demonstrates that ATA188 was tolerated well in all the four-dose cohorts. Patients that attained sustained disability improvement (SDI) at a specific timepoint maintained it’s in all future timepoints with a higher percentage of patients showing sustained disability improvements with dose escalation. The data was presented in an e-poster at MSVirtual2020: 8th Joint ACTRIMS-ECTRIMS Meeting held between September 11 and 13, 2020.

Jakob Dupont, the company’s R&D Global Head, indicated that the results are said that it was encouraging to see patients that received ATA188 had received SDI at any timepoint continue maintaining it at future points. The patients also showed improvement in physical function and fatigue after 12 months. He added that the results and ATA188’s favorable safety profile highlight its potential for patients having progressive multiple sclerosis. Dupont stated that it reinforces the company’s excitement on advancing the placebo-controlled randomized part of the study currently enrolling participants.

Atara currently enrolling patients for Phase 1b

The open-label Phase 1a multicentre ATA188 study was designed to establish tolerability and safety in patients having multiple sclerosis. It was also meant for selecting the recommended dose for the Phase 1b placebo-controlled randomized study that is enrolling participants currently. Patients in Phase 1a study received ATA188 in four dose escalation groups with six participants in Cohort 1-3 and seven in cohort 4. Results showed that all the study participants showed SDI at 6 months and maintained the SDI through 12 months.

The open-label extension (OLE) data with redosing at 12 months showed that those patients that had demonstrated SDI at 12 months continue to show SDI at 15 months. Also, a patient evaluated at 18 months showed SDI maintenance at the time with a fourth patient attaining SDI at 24 months.