United States Patent 5,178,878: A Detailed Analysis of Scope, Claims, and Patent Landscape
Introduction
United States Patent 5,178,878, titled "Effervescent dosage form with microparticles," was issued on January 12, 1993, to Cima Labs, Inc. This patent revolutionized the field of pharmaceutical orally ingested solid dosage forms by introducing a novel effervescent tablet design that incorporates microparticles.
Background and Context
Effervescent tablets have been used medicinally for many years, primarily to mask the taste of medicaments through the evolution of bubbles of gas in a liquid. However, traditional effervescent tablets required preparatory steps before administration, such as dissolving in water, which was inconvenient for patients[1].
Invention Overview
The patent describes an effervescent dosage form that includes microparticles designed to rupture upon chewing or to provide immediate release of the active ingredient. This innovation eliminates the need for preparatory steps, making the administration of medicaments more convenient and patient-friendly[1].
Key Components and Mechanism
Microparticles
The microparticles in this dosage form are crucial for the immediate release of the active ingredient. These particles can be designed to rupture upon chewing, ensuring rapid dissolution and absorption of the medicament[1].
Effervescent Agents
The patent highlights the use of effervescent disintegration agents that evolve gas through chemical reactions upon exposure to water or saliva. This mechanism aids in the rapid disintegration of the tablet and enhances the taste-masking effect[1].
Flavoring and Taste Masking
The composition includes flavoring agents to improve the palatability of the medicament. Preferred flavors such as grape, cherry, and citrus are mentioned, with the amount of flavoring ranging from about 0.5 to 3.0% by weight of the composition[1].
Manufacturing Process
The tablets can be manufactured using well-known tableting procedures. The material to be tableted is deposited into a cavity, and compressive force is applied using punch members to shape the material into the desired form. This process allows for high-volume production, with hundreds or thousands of tablets produced per minute[1].
Claims and Scope
Primary Claims
The patent claims cover the effervescent dosage form, the microparticles, and the method of manufacturing. Key claims include:
- The effervescent dosage form comprising microparticles that rupture upon chewing.
- The inclusion of effervescent agents that evolve gas upon exposure to water or saliva.
- The method of manufacturing involving compressive force to shape the material into tablets[1].
Scope of Protection
The scope of the patent is broad enough to cover various applications of the effervescent dosage form, including different types of medicaments and vitamins. However, it is narrowed by the specific requirements for the microparticles and the effervescent agents, ensuring that the invention is distinct from prior art[1].
Prior Art and Differentiation
The patent differentiates itself from prior art by addressing the inconvenience of traditional effervescent tablets. For example, U.S. Pat. No. 4,639,368 describes a chewing gum with a medicament and an effervescent agent, but it does not provide the immediate release mechanism of the microparticles in this patent[1].
Impact on Pharmaceutical Industry
The invention has had a significant impact on the pharmaceutical industry by providing a more convenient and patient-friendly way to administer medicaments. It has also paved the way for further innovations in oral dosage forms, particularly in the area of taste masking and rapid release mechanisms.
Patent Landscape
Related Patents
Other patents, such as U.S. Pat. No. 4,940,588, describe controlled-release microparticles, but these are not suitable for applications requiring rapid dissolution. The European Patent EP0752852A1 discusses effervescent formulations with base-coated acid particles, which, while related, do not incorporate the same immediate release mechanism as the microparticles in this patent[1][4].
Patent Quality and Scope
The debate over patent quality and scope is relevant here. Metrics such as independent claim length and independent claim count can be used to measure patent scope. This patent, with its specific claims and narrow scope, aligns with the trend of narrower claims being associated with a higher probability of grant and a shorter examination process[3].
Examination and Litigation
The examination process for this patent would have involved a thorough review to ensure that the claims were clear and not overly broad. Given the specific nature of the claims, it is likely that the patent was granted with a narrower scope, which would have reduced the likelihood of litigation and increased its validity[3].
Conclusion and Future Implications
United States Patent 5,178,878 has significantly contributed to the development of more convenient and effective oral dosage forms. Its innovative use of microparticles and effervescent agents has set a precedent for future pharmaceutical formulations.
Key Takeaways
- The patent introduces an effervescent dosage form with microparticles that rupture upon chewing.
- It eliminates the need for preparatory steps before administration.
- The use of effervescent agents enhances taste masking and rapid disintegration.
- The manufacturing process is efficient and scalable.
- The patent differentiates itself from prior art through its unique immediate release mechanism.
FAQs
What is the primary innovation of United States Patent 5,178,878?
The primary innovation is the use of microparticles that rupture upon chewing, providing immediate release of the active ingredient.
How does the effervescent agent work in this patent?
The effervescent agent evolves gas through chemical reactions upon exposure to water or saliva, aiding in the rapid disintegration of the tablet and enhancing taste masking.
What are the preferred flavors mentioned in the patent?
The preferred flavors are grape, cherry, and citrus.
How are the tablets manufactured according to this patent?
The tablets are manufactured using well-known tableting procedures involving compressive force to shape the material into the desired form.
What is the significance of the Acid Neutralization Constant (ANC) in related patents?
The ANC is significant in ensuring the stability of the effervescent formulation, particularly for acid-sensitive pharmaceutical compounds, and is maintained below 5.0 to avoid premature reaction and ensure performance[4].
