Atara Biotherapeutics, Inc. 8-K

What Happened
Atara Biotherapeutics announced on its Form 8-K (filed Jan 2, 2026) that on December 30, 2025 it entered into a Fourth Amendment to the Amended and Restated Commercialization Agreement with Pierre Fabre Medicament. The Amendment modifies the milestone payment structure related to tab-cel, including a reduction in the aggregate regulatory milestone amounts tied to FDA approval of a BLA.

Key Details

• Parties: Atara Biotherapeutics, Inc. and Pierre Fabre Medicament.
• Amendment date: December 30, 2025; original agreement dated October 31, 2023.
• Regulatory milestone change: aggregate potential milestone payments tied to FDA BLA approval for tab-cel reduced from $40.0 million to $31.0 million.
• Commercial milestone addition: the Amendment provides the Company the right to receive an additional $15.0 million potential milestone payment upon achieving a specified commercial milestone.
• The Fourth Amendment is filed as Exhibit 10.1 to the Form 8-K.

Why It Matters
This is a contractual change to the company’s collaboration with Pierre Fabre that alters the timing and amount of potential partner-funded milestone receipts. For investors, the amendment directly affects the structure of future contingent cash inflows tied to tab-cel’s regulatory and commercial progress; it does not report any regulatory approvals or new financing. Review the filed Amendment (Exhibit 10.1) for the full terms and any conditions that determine when those milestone payments would be earned.