Xencor Enters Global Collaboration and License Agreement With Janssen to Advance Plamotamab and XmAb CD28 Bispecific Antibody Combinations for the Treatment of Patients With B-Cell Malignancies

Xencor, Inc. a clinical-stage biopharmaceutical company developing engineered monoclonal antibodies and cytokines for the treatment of cancer and autoimmune diseases, announced an exclusive collaboration and worldwide license agreement with Janssen Biotech, Inc., one of the Janssen Pharmaceutical Companies of Johnson & Johnson, to develop and commercialize plamotamab and novel XmAb B-cell targeting bispecific antibodies that are designed to conditionally activate T cells through the CD28 co-stimulatory receptor. Plamotamab is a CD20 x CD3 XmAb bispecific antibody and is currently completing a Phase 1 dose-escalation study in patients with CD20-expressing hematologic malignancies.

“The treatment landscape in B-cell lymphoma will potentially be redefined by CD20 x CD3 bispecific antibodies, such as plamotamab, and the best outcomes for patients will require creative combination approaches using complementary mechanisms of action. We are delighted to collaborate with Janssen’s leading scientists to expand the scope of the plamotamab program, particularly as we explore opportunities to combine with novel B-cell targeted CD28 bispecific antibodies that can potentially selectively enhance T-cell cytotoxic activity,” said Bassil Dahiyat, Ph.D., president and chief executive officer at Xencor. “This collaboration complements our plans to initiate combination clinical trials of plamotamab with tafasitamab and lenalidomide, and it expands our strategy to develop multiple highly active chemotherapy-free regimens for B-cell cancers.”

Under the terms of the agreement, Janssen will receive worldwide exclusive development and commercialization rights to plamotamab, whether as a monotherapy or in combination regimens. Xencor will collaborate with Janssen on further clinical development of plamotamab with Janssen paying 80% and Xencor paying 20% of costs, including those for a subcutaneous formulation anticipated to enter clinical trials in 2022. In parallel, Xencor will continue, at its own expense, a previously announced clinical collaboration to evaluate the combination of plamotamab, tafasitamab and lenalidomide in patients with B-cell lymphoma, including a Phase 2 trial in relapsed or refractory diffuse large B-cell lymphoma anticipated to start in late 2021 or early 2022.

Further, Xencor will apply its XmAb bispecific Fc technology to create and characterize XmAb CD28 bispecific antibody candidates against B-cell targets during a two-year joint research collaboration, and Janssen will have an exclusive worldwide license to develop selected molecules in combination with plamotamab and other agents, such as CD3 bispecific antibodies.

Xencor will receive an upfront payment of $100 million, and Johnson & Johnson Innovation – JJDC, Inc. will purchase $25 million of newly issued shares of Xencor common stock. Xencor will be eligible to receive up to $1.188 billion in potential development, regulatory and sales milestone payments, as well as tiered royalties on net sales of products developed under the agreement, ranging from mid-teen to low-twenties percentages for products containing plamotamab and plamotamab/CD28 bispecific antibody combinations. Separate terms apply to CD28 bispecific antibodies commercialized outside of a plamotamab combination, where Xencor retains an option to co-fund development costs in exchange for higher royalties and the right to co-detail such products in the United States.

The agreement is subject to customary closing conditions, including clearance under the Hart-Scott-Rodino Antitrust Improvements Act, and closing is expected to occur in the fourth quarter of 2021.