How Genentech's Antibody Targets Cancerous B Cells

This patent describes a specific humanized antibody designed to bind to a protein called CD79b, which is found on the surface of certain cancer cells.

What it covers

The patent claims a specific molecular structure for an antibody that targets the CD79b protein. Antibodies are Y-shaped proteins that the immune system uses to identify foreign objects. By defining precise amino acid sequences for the hypervariable regions (the parts of the antibody that 'grab' onto a target), this patent creates a highly specific key for the CD79b lock. When these antibodies bind to CD79b on the surface of B cells, they can be used to tag those cells for destruction, particularly in patients with B-cell cancers like lymphoma or leukemia.

What it doesn't cover

• —Does not cover antibodies that use different amino acid sequences for the hypervariable regions defined in claim 1.
• —Does not cover general methods for creating humanized antibodies that do not utilize the specific sequences listed.
• —Does not cover targeting proteins other than CD79b.
• —Does not cover the use of these antibodies for non-medical or non-diagnostic purposes.

The clever bit

The patent identifies a very specific epitope (the exact spot on the CD79b protein) that allows the antibody to bind effectively even when the protein is expressed on the surface of a living B cell, which is often difficult due to the cell's complex environment.

Why it matters

CD79b is a critical marker for B-cell malignancies. This patent provides the intellectual property foundation for targeted therapies, such as antibody-drug conjugates, which deliver toxic payloads directly to cancer cells while sparing healthy tissue. It is a key component of Genentech's oncology portfolio, specifically supporting the development of drugs like Polatuzumab vedotin (Polivy).

Real-world examples

• 1.Polatuzumab vedotin (Polivy) used for treating diffuse large B-cell lymphoma