United States Patent 5,624,668: A Detailed Analysis of Scope, Claims, and Patent Landscape
Introduction
United States Patent 5,624,668, titled "Iron Dextran Formulations," is a significant patent in the field of medical science, particularly in the treatment of iron deficiency. This patent, which has since expired, provides valuable insights into the formulation, production, and application of iron dextran complexes.
Background
Iron dextran is an iron supplement used to treat iron deficiency in patients who cannot take oral iron. It is administered intramuscularly or intravenously and is absorbed into the capillaries and lymphatic system[1][4].
Scope of the Patent
The patent focuses on the development and characterization of iron dextran formulations. Here are the key aspects of its scope:
Formulation
The patent describes the process of preparing iron dextran complexes, which involves the reaction of iron salts with dextran, a polysaccharide. The formulation includes the use of oxidized dextran to ensure uniformity and to avoid the presence of endotoxins[1].
Molecular Weight
The molecular weight of the iron dextran complex is a critical parameter. The patent details the use of gel permeation chromatography (GPC) to determine the molecular weight, which is essential for ensuring the stability and efficacy of the formulation. The GPC system uses polyacrylic acid columns to separate molecules based on size, allowing for the calculation of weight average molecular weight (Mw), number average molecular weight (Mn), and polydispersity index (Mw/Mn)[1].
Stability and Safety
The patent emphasizes the importance of stability and safety in the formulation. It discusses the adjustment of pH and the control of chloride content to ensure the product's stability and minimize adverse reactions. The maximum amount of hydrochloric acid used is calculated to stay within the desired limits for chloride content[1].
Claims of the Patent
The claims of the patent are detailed and specific, covering various aspects of the iron dextran formulations:
Composition
The patent claims cover the composition of the iron dextran complex, including the molecular weight range of the dextran and the amount of iron bound to the dextran. It specifies that the dextran must be oxidized to avoid uniformity issues and the presence of endotoxins[1].
Method of Preparation
The claims include the method of preparing the iron dextran complex, which involves reacting iron salts with oxidized dextran and adjusting the pH and chloride content[1].
Physical and Galenical Forms
The patent claims also cover the physical and galenical forms of the iron dextran complex, such as particulate, powder, or other forms suitable for medical use[1].
Patent Landscape
The patent landscape surrounding iron dextran formulations is complex and evolving:
Related Patents
Other patents, such as those described in the Justia database, focus on aqueous iron carbohydrate complexes and their production. These patents highlight advancements in stability and dosage, allowing for higher application rates and single-dose treatments[2].
Industry Trends
The trend in the pharmaceutical industry is towards more stable and efficient iron supplements. Patents like US5624668A have paved the way for newer formulations that offer improved safety profiles and higher bioavailability[2].
Regulatory Considerations
The patent scope and claims are influenced by regulatory requirements. For instance, the control of chloride content and pH adjustment are critical to ensure compliance with safety standards. The patent's emphasis on these aspects reflects the stringent regulatory environment in the pharmaceutical industry[1].
Impact on Medical Practice
The iron dextran formulations described in this patent have had a significant impact on medical practice:
Treatment of Iron Deficiency
Iron dextran is a crucial treatment option for patients with iron deficiency who cannot tolerate oral iron supplements. The formulations developed under this patent have improved the efficacy and safety of such treatments[4].
Clinical Use
The patent's detailed characterization of the iron dextran complex has helped in standardizing the product for clinical use. This includes the specification of molecular weight and the method of preparation, which are essential for ensuring consistent quality[1].
Key Takeaways
- Formulation and Preparation: The patent details the preparation of iron dextran complexes using oxidized dextran and specifies the importance of molecular weight and pH adjustment.
- Stability and Safety: The patent emphasizes the control of chloride content and pH to ensure stability and safety.
- Regulatory Compliance: The patent reflects the need for compliance with regulatory standards in the pharmaceutical industry.
- Clinical Impact: The formulations have improved the treatment of iron deficiency, especially for patients who cannot take oral iron supplements.
FAQs
What is the primary use of iron dextran formulations?
Iron dextran formulations are used to treat iron deficiency in patients who cannot take oral iron supplements.
How are iron dextran complexes prepared?
Iron dextran complexes are prepared by reacting iron salts with oxidized dextran and adjusting the pH and chloride content.
Why is molecular weight important in iron dextran formulations?
Molecular weight is crucial for ensuring the stability and efficacy of the iron dextran complex. It is determined using gel permeation chromatography (GPC).
What are the safety considerations in iron dextran formulations?
Safety considerations include the control of chloride content and pH adjustment to minimize adverse reactions and ensure stability.
Are there other patents related to iron dextran formulations?
Yes, other patents focus on aqueous iron carbohydrate complexes and their production, highlighting advancements in stability and dosage.
Sources
- US5624668A - Iron dextran formulations - Google Patents
- Aqueous iron carbohydrate complexes, their production and ... - Justia
- Patent Claims and Patent Scope - Hoover Institution
- Iron Dextran: Uses, Interactions, Mechanism of Action - DrugBank
