# Using Antibodies to Target Tissue Factor Without Stopping Blood Clotting

> A patent describing specific antibodies that attach to a protein called tissue factor without interfering with the body's natural blood-clotting process.

- **Patent:** US 7993644
- **Original title:** Tissue factor antibodies and uses thereof
- **Owner:** Purdue Pharma LP
- **Granted:** 2011
- **Status:** Active
- **Times cited:** 3
- **Field:** biotech, pharmaceutical

## What it does

This patent identifies specific antibodies that bind to human tissue factor, a protein often found in high amounts on cancer cells. Unlike many other antibodies that might block tissue factor, these are specifically selected because they do not inhibit blood coagulation, which is vital for patient safety. The patent covers the specific hybridoma cell lines (TF260, TF196, etc.) that produce these antibodies. It also details how these antibodies can be linked to cytotoxic agents—essentially toxic drugs—to deliver them directly to cells expressing tissue factor, or to detectable agents for imaging purposes.

## What it does NOT cover

- Does not cover antibodies that inhibit or block the normal blood coagulation process.
- Does not cover general methods for creating antibodies that are not derived from the specific deposited hybridoma lines.
- Does not cover the use of tissue factor antibodies for purposes other than binding to the protein without affecting clotting.

## The clever bit

The innovation lies in selecting antibodies that bind to tissue factor without interfering with its physiological role in the coagulation cascade, effectively decoupling the therapeutic targeting from the risk of hemorrhage.

## Real-world examples

1. Targeted cancer therapy research
2. Diagnostic imaging for tumors expressing tissue factor

## Why it matters

Tissue factor is a key target in cancer therapy because it is frequently overexpressed in tumors. The challenge in targeting it is that tissue factor is also essential for blood clotting; inhibiting it can lead to dangerous bleeding. This patent provides a way to target the protein for therapy or imaging while leaving the body's clotting mechanism intact.

## Frequently asked questions

### What does Using Antibodies to Target Tissue Factor Without Stopping Blood Clotting cover?

A patent describing specific antibodies that attach to a protein called tissue factor without interfering with the body's natural blood-clotting process.

### Who owns patent US 7993644?

Purdue Pharma LP owns this patent, granted in 2011.

### When does this patent expire?

This patent is expected to expire on August 9, 2031, when the invention enters the public domain.

### What is patent US 7993644 cited by?

This patent has been cited by 3 later patents that build on its ideas.

### What problem does this patent solve?

Tissue factor is a key target in cancer therapy because it is frequently overexpressed in tumors. The challenge in targeting it is that tissue factor is also essential for blood clotting; inhibiting it can lead to dangerous bleeding. This patent provides a way to target the protein for therapy or imaging while leaving the body's clotting mechanism intact.

### What does this patent NOT cover?

Does not cover antibodies that inhibit or block the normal blood coagulation process.

**Full plain-English explainer:** https://patentbrief.org/patent/us/7993644/stelara-ustekinumab

**Original patent:** https://patents.google.com/patent/US7993644

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