# How Specialized Nanobodies Block Blood Clotting Proteins

> A patent describing specific, tiny antibody fragments designed to bind to and inhibit Von Willebrand Factor, a protein that triggers blood clotting.

- **Patent:** US 8372398
- **Original title:** Single domain VHH antibodies against Von Willebrand Factor
- **Owner:** Ablynx NV
- **Granted:** 2013
- **Status:** Active
- **Times cited:** 9
- **Field:** biotech, pharmaceutical

## What it does

This patent claims specific protein sequences known as Nanobodies that target Von Willebrand Factor (vWF). vWF is a protein in the blood that acts like glue, helping platelets stick together to form clots. By binding to vWF using specific amino acid sequences in their 'complementarity determining regions' (the parts of the antibody that actually grab the target), these Nanobodies prevent the protein from functioning. This effectively stops the blood from clotting in situations where it might be dangerous, such as in certain cardiovascular diseases.

## What it does NOT cover

- Does not cover general-purpose antibodies derived from traditional, large-format immune systems.
- Does not cover Nanobodies that target proteins other than Von Willebrand Factor.
- Does not cover amino acid sequences outside of the specific CDR combinations defined in the claims.
- Does not cover methods of manufacturing Nanobodies that do not involve the specific sequences listed.

## The clever bit

The innovation lies in the extreme smallness of the VHH domain (a single-domain antibody), which allows it to reach 'hidden' binding sites on the vWF protein that larger, traditional antibodies cannot access.

## Real-world examples

1. Caplacizumab (Cablivi)

## Why it matters

This technology is central to the development of Caplacizumab, a drug used to treat acquired thrombotic thrombocytopenic purpura (a rare blood disorder). By using small, stable Nanobodies instead of large antibodies, researchers created a drug that can be highly specific and potentially easier for the body to process. It represents a shift toward using 'domain antibodies' in modern medicine.

## Frequently asked questions

### What does How Specialized Nanobodies Block Blood Clotting Proteins cover?

A patent describing specific, tiny antibody fragments designed to bind to and inhibit Von Willebrand Factor, a protein that triggers blood clotting.

### Who owns patent US 8372398?

Ablynx NV owns this patent, granted in 2013.

### When does this patent expire?

This patent is expected to expire on February 12, 2033, when the invention enters the public domain.

### What is patent US 8372398 cited by?

This patent has been cited by 9 later patents that build on its ideas.

### What problem does this patent solve?

This technology is central to the development of Caplacizumab, a drug used to treat acquired thrombotic thrombocytopenic purpura (a rare blood disorder). By using small, stable Nanobodies instead of large antibodies, researchers created a drug that can be highly specific and potentially easier for the body to process. It represents a shift toward using 'domain antibodies' in modern medicine.

### What does this patent NOT cover?

Does not cover general-purpose antibodies derived from traditional, large-format immune systems.

**Full plain-English explainer:** https://patentbrief.org/patent/us/8372398/subcutaneous-herceptin

**Original patent:** https://patents.google.com/patent/US8372398

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_Source: PatentBrief — https://patentbrief.org. Patent facts are from public records; the plain-English explanation is PatentBrief's._