Vardenafil Hydrochloride Trihydrate Stability via Stearic Acid
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Vardenafil hydrochloride trihydrate in existing pharmaceutical formulations is prone to converting into its base form during storage, affecting stability and bioavailability due to variable water content and ambient conditions, leading to inconsistent plasma concentrations and reduced efficacy.
Innovation Solution
A stable pharmaceutical formulation of Vardenafil hydrochloride trihydrate is achieved by incorporating stearic acid and other pharmaceutically acceptable excipients, such as microcrystalline cellulose and crospovidone, which prevents the conversion to the base form through dry granulation and compression, maintaining stability without exposure to humidified gas during processing.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Reliability
If Vardenafil hydrochloride trihydrate is used in conventional pharmaceutical formulations without additional stabilizing agents, then the formulation is simple to manufacture, but the active substance converts into its base form during storage, reducing stability and bioavailability
Solution Approach 1:
Stearic acid is introduced as an intermediary substance that mediates between the Vardenafil hydrochloride trihydrate and the environment. It forms a protective interaction with the active substance, preventing conversion to the base form without requiring complex formulation systems or controlled storage conditions
Solution Approach 2:
The invention creates a composite pharmaceutical formulation by combining Vardenafil hydrochloride trihydrate with stearic acid and other excipients. This composite structure provides enhanced stability to the active substance while maintaining manufacturability and addressing the conversion issue through material composition rather than process complexity
2Stability of the object's composition
If Vardenafil hydrochloride trihydrate is exposed to humidified gas during processing to maintain trihydrate form, then the trihydrate form is stabilized, but the processing complexity increases and controlled humidity conditions are required
Solution Approach 1:
Stearic acid is incorporated into the formulation during the manufacturing process, performing a preliminary stabilizing action that prevents future conversion of the trihydrate form. This eliminates the need for subsequent exposure to humidified gas or controlled humidity conditions during storage and handling
Solution Approach 2:
The formulation becomes self-stabilizing through the inclusion of stearic acid, which continuously protects the Vardenafil hydrochloride trihydrate from converting to the base form. The system maintains the trihydrate form through its own composition rather than requiring external control measures
3Ease of manufacture
If magnesium stearate is used as a lubricant in the formulation, then the manufacturing process is facilitated, but it promotes the conversion of Vardenafil hydrochloride trihydrate to the base form, reducing stability
Solution Approach 1:
The invention changes the chemical parameter of the lubricant from magnesium stearate to stearic acid. This parameter change fundamentally alters the interaction with Vardenafil hydrochloride trihydrate, preventing the conversion to base form while still providing the necessary lubricating function for manufacturing
Solution Approach 2:
The invention converts the potential harm of using a lubricant that causes conversion into a benefit by selecting stearic acid, which provides both lubrication for easy manufacturing and simultaneous protection against conversion. The same class of compound (fatty acid-based lubricant) is used, but with beneficial properties
Data Source
Figure 1
Figure 1a
Figure 2
AI summary
The invention relates to a pharmaceutical formulation for oral administration, the formulation containing an effective quantity of Vardenafil hydrochloride or Vardenafil hydrochloride trihydrate, stearic acid and at least one further pharmaceutically acceptable excipient. A further solution provides a process for the preparation of said formulation.