Targeted Platinum Drugs for Cancer Treatment

This patent describes a way to deliver platinum-based cancer drugs directly to tumor cells by attaching them to a special 'ligand' molecule that seeks out cancer cell markers.

What it covers

This patent describes a 'ligand drug conjugate' (LDC) designed to deliver chemotherapy drugs specifically to cancer cells. The LDC works by connecting a 'ligand' (a molecule that can find and stick to specific targets) to a 'functional moiety,' which is then linked to a 'coordination metal complex' containing platinum (II). This platinum complex is, in turn, connected to a drug. The ligand is designed to bind to a 'protein, receptor, or cell marker on a surface of a cancer cell' (claims 2, 9), acting like a homing beacon. The connections between these parts are made by 'linkers,' which can be simple chains like hydrocarbons or more complex ones like polyethylene glycol (PEG), amino acids, or peptides (claims 3, 10). For example, a ligand might specifically recognize a unique protein found only on the surface of lung cancer cells, guiding the attached platinum drug directly to those cells to treat the cancer (claims 5, 11) while minimizing harm to healthy tissues.

What it doesn't cover

• —Does not cover non-targeted platinum drugs that distribute throughout the body without a specific cancer cell homing mechanism.
• —Does not cover targeted drug conjugates that use metal complexes other than platinum (II) as the central coordination component.
• —Does not cover targeted drug conjugates where the drug is not connected via a platinum (II) coordination complex.
• —Does not cover methods of treating diseases other than cancer using these specific conjugates.
• —Does not cover targeting mechanisms that do not involve a ligand binding to a protein, receptor, or cell marker on a cancer cell's surface.

The clever bit

The clever part is the specific chemical architecture of the drug conjugate, particularly the inclusion of a platinum (II) coordination complex as a central, structured component that links the drug to the targeting ligand. This design allows for the precise, targeted delivery of platinum-based chemotherapy agents, aiming to improve their therapeutic index by localizing their activity.

Why it matters

Traditional platinum-based chemotherapy drugs are effective against many cancers but often cause severe side effects because they harm healthy cells along with cancer cells. This patent addresses that problem by proposing a way to target these powerful drugs directly to tumors. By concentrating the drug at the cancer site, it aims to increase effectiveness while reducing harmful side effects, which is a major goal in modern oncology.

Real-world examples

• 1.Cisplatin (a non-targeted platinum drug)
• 2.Carboplatin (another non-targeted platinum drug)
• 3.Antibody-drug conjugates (ADCs) in cancer therapy
• 4.Targeted chemotherapy for solid tumors