Targeting Drugs to Specific Body Tissues Using ApoE3-Coated Nanoparticles

This patent describes a method to deliver drugs or diagnostic agents precisely to target cells or tissues, including the brain, by packaging them inside tiny fat particles (lipid nanoparticles) coated with a special protein called ApoE3.

What it covers

This patent details a method for improving how therapeutic agents reach specific cells or tissues in the body. It uses a lipid nanoparticle (a tiny fat-based sphere) that carries a drug or diagnostic agent inside (Claim 1). The key is that this nanoparticle has a human recombinant apolipoprotein (ApoE3) attached to its surface, but without Polysorbate 80 (Claim 1). This ApoE3 coating helps the nanoparticle get preferentially absorbed by tissues like the brain, lung, kidney, and liver that have many LDL receptors (Claim 1). For example, the patent explains how this system can deliver a chemotherapy drug specifically to brain cancer cells by helping it cross the blood-brain barrier (Claim 10), or even an antibiotic like Amphotericin B to treat brain infections (Claim 12).

What it doesn't cover

• —Does not cover lipid nanoparticles that use Polysorbate 80 in their surface coating, as the claims specifically exclude it (Claim 1).
• —Does not cover drug delivery systems where the therapeutic agent is chemically attached (conjugated) to the nanoparticle (Claim 3).
• —Does not cover drug delivery where the ApoE3 is not adsorbed to the surface of the nanoparticle, but perhaps integrated differently (Claim 1).
• —Does not cover drug delivery to tissues that do not overexpress LDL receptors, unless the transport mechanism is explicitly through transcytosis independent of LDL receptor binding (Claim 1 and Claim 11).
• —Does not cover nanoparticles that do not contain both a triglyceride and a cholesterol ester component in their lipid core (Claim 1).

The clever bit

The clever part is using ApoE3, a naturally occurring protein, to 'trick' cells and the blood-brain barrier into taking up drug-loaded nanoparticles. By adsorbing ApoE3 to the nanoparticle surface, the system either targets cells that overexpress LDL receptors or facilitates transport across the blood-brain barrier via transcytosis, ensuring the therapeutic agent reaches its destination more efficiently.

Why it matters

Delivering drugs effectively to specific parts of the body, especially the brain, is a major challenge in medicine. Many drugs cannot cross the blood-brain barrier, limiting treatments for brain cancers, infections, and neurological disorders. This patent offers a way to overcome these barriers, potentially making existing drugs more effective and less toxic by concentrating them where they are needed most. This targeted approach could improve patient outcomes and reduce side effects.

Real-world examples

• 1.Targeted chemotherapy for brain tumors
• 2.Delivery of antibiotics for brain infections like Candida albicans
• 3.Enhanced delivery of MRI contrast agents for brain imaging
• 4.Drug delivery to lung, kidney, and liver tissues with high LDL receptor expression