Methods, Therapies and Uses for Treating Cancer BCMA Bispecific Antibody Combinations for Multiple Myeloma

This patent covers single agent and combination therapies for B-cell related cancers using a BCMA x CD3 bispecific antibody, with named combinations including anti-PD-1 antibodies, anti-PD-L1 antibodies, immunomodulating drugs such as lenalidomide and pomalidomide, and gamma secretase inhibitors.

The Problem

B-cell maturation antigen (BCMA), also known as CD269 or TNFRSF17, is a member of the tumour necrosis factor receptor superfamily that is selectively expressed on plasma cells and plasmablasts. Its restricted expression makes it an attractive target in multiple myeloma, where the malignant cells almost universally retain BCMA on their surface. A range of BCMA-directed therapies have entered the clinic, including antibody-drug conjugates, CAR-T cell products, and bispecific antibodies that recruit T cells via CD3. Despite these advances, multiple myeloma remains incurable. Patients typically respond to a BCMA-directed agent, then relapse as the malignant clone develops resistance. Soluble BCMA released into the bloodstream can also act as a decoy sink for BCMA-targeting drugs, blunting their effect. The clinical need is for combinations that extend the duration of response, overcome resistance mechanisms, and rescue patients whose disease has progressed on prior BCMA monotherapy.

What This Invention Does

The invention provides methods of treating cancer, principally multiple myeloma and other B-cell malignancies, by administering a BCMA-specific therapeutic in combination with a second agent. In its preferred embodiments, the BCMA-specific therapeutic is the BCMA x CD3 bispecific antibody PF-06863135 (elranatamab), and the second therapeutic agent is one of: an anti-PD-1 antibody (such as Pfizer’s sasanlimab), an anti-PD-L1 antibody, an immunomodulating drug (lenalidomide or pomalidomide), or a gamma secretase inhibitor (nirogacestat). The claims also cover three-agent, four-agent, and five-agent combinations that add chemotherapy, and they specify a wide range of dosing schedules and routes (intravenous, subcutaneous, oral) and dose levels spanning micrograms per kilogram up to fixed doses of more than one gram. The patent is a divisional of AU 2021339096, which itself entered Australia as the national phase of PCT/IB2021/058229 (WO 2022/053990).

Key Features

• BCMA x CD3 bispecific antibody backbone. The combinations are built around a bispecific antibody (PF-06863135 / elranatamab) that simultaneously binds BCMA on the myeloma cell and CD3 on a T cell, redirecting cytotoxic T cells to kill the malignant plasma cell.
• Checkpoint inhibitor pairing. Combining the bispecific with an anti-PD-1 antibody (sasanlimab) or anti-PD-L1 antibody is intended to keep recruited T cells from being switched off by PD-1 / PD-L1 signalling in the tumour microenvironment, addressing a known mechanism of T-cell exhaustion in myeloma.
• Immunomodulating drug pairing. Adding lenalidomide or pomalidomide leverages the existing standard-of-care backbone in multiple myeloma. These agents have direct anti-myeloma activity and also enhance T-cell and NK-cell function, which may potentiate the bispecific.
• Gamma secretase inhibitor pairing. Pairing the bispecific with nirogacestat blocks the proteolytic cleavage of BCMA from the cell surface, increasing membrane BCMA available for antibody binding and reducing the soluble BCMA decoy sink that limits efficacy.
• Broad disease scope. Claims extend across multiple myeloma, malignant plasma cell neoplasms, Hodgkin’s and non-Hodgkin’s lymphoma, nodular lymphocyte predominant variants, chronic lymphocytic leukaemia, and other B-cell related cancers.

Who Is Behind It?

The applicant is Pfizer Inc., headquartered in New York, USA. The named inventors are Geoffrey Wing-Lynn Chan, Jeffrey Chou, Mohamed A. Elmeliegy, Heike Iris Krupka, John Andrew Blake-Haskins, Eloisa Virginia Barry, Nathalie Annie Bardy Bouxin, Kai Hsin Liao, Anne Yver, Paul Stephen Wissel, Andrea Viqueira, and Erik Rene Vandendries, a clinical, translational, and pharmacology team consistent with a phase 1 / 2 development program. The Australian patent attorney is Davies Collison Cave in Melbourne. The application is a divisional of AU 2021339096 (national phase of PCT/IB2021/058229, published as WO 2022/053990) with priority from September 2020.

Why It Matters

Elranatamab (Elrexfio) is Pfizer’s BCMA x CD3 bispecific antibody for relapsed or refractory multiple myeloma. It received accelerated approval from the US FDA in August 2023 and conditional marketing authorisation in the European Union shortly afterwards, joining Janssen‘s teclistamab in a competitive BCMA bispecific class. Multiple myeloma affects roughly 2,500 Australians each year and has historically required a sequence of treatment lines as patients relapse. Combination strategies that pair bispecifics with checkpoint inhibitors, immunomodulators, or BCMA shedding blockers are the next phase of development, aimed at deepening responses and delaying or preventing relapse. Australian patent protection on these combinations is commercially significant because PBS reimbursement, formulary listing, and clinical trial activity in Australia will all turn on the regulatory and IP position of these specific pairings.

Related Concepts

Elranatamab is one of a growing family of bispecific antibodies that redirect CD3-positive T cells against tumour antigens, a strategy that also underpins CAR-T cell therapy. Combining these agents with immune checkpoint inhibitors targeting PD-1 or PD-L1 is intended to keep recruited T cells active in the immunosuppressive myeloma microenvironment.

For Australian patients, access to these therapies turns on decisions by the TGA and on subsequent listing through the Pharmaceutical Benefits Scheme.

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AU 2026201847 was published in the Australian Official Journal of Patents on 2 April 2026 and is open for public inspection. Patent applications represent inventions that are sought to be protected and do not necessarily reflect commercially available products.