# How a Specific Eye Drop Formula Treats Glaucoma > A patent for a precise, low-concentration eye drop solution designed to lower eye pressure in patients with glaucoma or ocular hypertension. - **Patent:** US RE48183 - **Original title:** USRE48183E1 - Pharmaceutical formulations comprising a pyridylaminoacetic acid compound - **Owner:** Santen Pharmaceutical Co Ltd - **Granted:** 2020 - **Status:** Active - **Times cited:** 1 - **Field:** biotech, pharmaceutical ## What it does This patent covers a specific pharmaceutical liquid formulation used as an eye drop to treat glaucoma. The active ingredient is a chemical compound called isopropyl(6-{[4-(pyrazol-1-yl)benzyl](pyridin-3-ylsulfonyl)aminomethyl}pyridin-2-ylamino)acetate. The claims define a very narrow concentration range of this ingredient, specifically between 0.001% and 0.003% (weight/volume), while maintaining a pH balance between 4.0 and 8.0. This precise mixture is intended to be applied directly to the eye to reduce intraocular pressure. ## What it does NOT cover - Does not cover concentrations of the active ingredient outside the 0.001% to 0.003% (w/v) range. - Does not cover formulations with a pH level outside the 4.0 to 8.0 range. - Does not cover the chemical compound itself, only this specific pharmaceutical preparation. - Does not cover delivery methods other than eye drops or topical instillation. ## The clever bit The invention focuses on a very specific 'sweet spot' concentration range that provides the necessary pressure-lowering effect while likely minimizing the irritation or toxicity often associated with higher doses of such compounds. ## Real-world examples 1. Rhopressa (netarsudil) or similar Rho kinase inhibitor eye drops 2. Prescription glaucoma eye drop medications ## Why it matters Glaucoma is a leading cause of blindness, and managing intraocular pressure is the primary treatment. By patenting a specific, highly diluted concentration, the assignee protects a formulation that likely balances efficacy with reduced side effects or improved stability, which is critical for daily patient compliance. ## Frequently asked questions ### What does How a Specific Eye Drop Formula Treats Glaucoma cover? A patent for a precise, low-concentration eye drop solution designed to lower eye pressure in patients with glaucoma or ocular hypertension. ### Who owns patent US RE48183? Santen Pharmaceutical Co Ltd owns this patent, granted in 2020. ### When does this patent expire? This patent is expected to expire on September 1, 2040, when the invention enters the public domain. ### What is patent US RE48183 cited by? This patent has been cited by 1 later patents that build on its ideas. ### What problem does this patent solve? Glaucoma is a leading cause of blindness, and managing intraocular pressure is the primary treatment. By patenting a specific, highly diluted concentration, the assignee protects a formulation that likely balances efficacy with reduced side effects or improved stability, which is critical for daily patient compliance. ### What does this patent NOT cover? Does not cover concentrations of the active ingredient outside the 0.001% to 0.003% (w/v) range. **Full plain-English explainer:** https://patentbrief.org/patent/us/RE48183/trikafta-triple-combination **Original patent:** https://patents.google.com/patent/USRE48183 --- _Source: PatentBrief — https://patentbrief.org. Patent facts are from public records; the plain-English explanation is PatentBrief's._ ## Related patents Semantically similar inventions in the PatentBrief corpus: - [How Polystyrene Sulfonate Helps Treat Dry Eye Symptoms](https://patentbrief.org/patent/us/3987163/indomethacin) — A 1975 patent for an eye drop solution that uses a specific polymer to lubricate and cushion the eye, especially for contact lens wearers. - [How to Keep High-Concentration Antibody Medicines Stable in Liquid Form](https://patentbrief.org/patent/us/7740842/herceptin-adjuvant-therapy) — Novartis's patent describes a specific liquid recipe for keeping high concentrations of E25 anti-IgE antibodies stable and usable for medical injections. - [Preventing Protein Damage with Extra Methionine](https://patentbrief.org/patent/us/5272135/lipitor-atorvastatin) — This 1993 patent describes how adding extra methionine to protein-based medicines can prevent them from degrading, especially in liquid or semi-solid forms. - [How to Make Long-Lasting Injections for Multiple Sclerosis Treatment](https://patentbrief.org/patent/us/RE50301/temperature-controlled-mug) — A patent for a slow-release version of the MS drug glatiramer acetate, designed to be injected once every week to six months instead of daily. - [How Specific Antibody Drugs Are Stabilized for Storage and Use](https://patentbrief.org/patent/us/8372396/tysabri-natalizumab) — Genentech's 2013 patent details a precise recipe for an antibody drug, like Pertuzumab, using a special buffer, sugar, and cleaning agent to keep it stable for patients.