Targeting Cancer with CAR T Cells Using a Chemical Tag

This patent describes a method to treat cancer by giving a patient special immune cells (CAR T cells) that recognize a chemical tag, which is attached to a small drug molecule, along with a separate folate compound.

What it covers

The patent outlines a three-step method to treat cancer. First, a patient receives a compound where a small drug molecule is connected to a "targeting moiety" (like a chemical tag) by a "linker" (Claim 1(i)). Second, the patient gets CAR T cells, which are engineered immune cells designed to specifically recognize and bind to this "targeting moiety" (Claim 1(ii)). Third, a "folate conjugate" is administered, which is a folate molecule linked to other parts, but importantly, this conjugate *does not* have the targeting moiety that the CAR T cells recognize (Claim 1(iii)). For example, if the targeting moiety is FITC (Claim 3), the CAR T cells would have an anti-FITC antibody part (Claim 12) to find and attack cells marked by the FITC-tagged compound.

What it doesn't cover

• —Does not cover methods where the initial compound (small molecule ligand + linker + targeting moiety) is an antibody or an antibody fragment (Claim 11).
• —Does not cover CAR T cell therapies where the CAR T cells directly target cancer cells without an intermediate targeting moiety.
• —Does not cover methods where the administered folate conjugate also contains the specific targeting moiety that the CAR T cells are designed to recognize (Claim 1(iii)).
• —Does not cover methods that do not involve all three distinct administration steps: the compound, the CAR T cells, and the folate conjugate (Claim 1).

The clever bit

The novelty lies in the indirect targeting approach. Instead of engineering CAR T cells to directly attack cancer cells, this method uses a separate, small molecule compound to "tag" cancer cells. The CAR T cells then attack only those tagged cells, offering a potential way to fine-tune the therapy's activity and reduce off-target effects.

Why it matters

CAR T cell therapy is a powerful way to fight cancer, but it can sometimes cause severe side effects. This patent aims to improve the safety and control of CAR T cell treatments. By using a "targeting moiety" as an intermediate tag, doctors might be able to better control when and where the CAR T cells become active, potentially reducing harm to healthy tissues while still effectively attacking tumors.

Real-world examples

• 1.CAR T cell therapies for blood cancers like lymphoma and leukemia
• 2.Potential future CAR T cell therapies for solid tumors
• 3.Immunotherapies using small molecule drug conjugates