Liquid Topical Preparation with Dicarboxylic Acid Ester

Resolve Bottlenecks,
Find Innovative SolutionsGenerate Solutions

Solution Overview

Problem

High concentrations of anticholinergic drugs in liquid topical preparations lead to increased stickiness, reducing comfort and effectiveness in treating hyperhidrosis.

Innovation Solution

Incorporating a dicarboxylic acid ester, such as diisopropyl adipate or diethyl sebacate, into the preparation to suppress stickiness while maintaining a high concentration of anticholinergic drugs like oxybutynin, along with optional salts like sodium lactate to enhance skin accumulation.

Engineering Contradictions & Design Principles

VSEngineering Contradiction Analysis

1Reliability

If the content of anticholinergic drug is increased to improve therapeutic effectiveness, then the effectiveness in treating hyperhidrosis is improved, but stickiness increases and comfortableness decreases

Engineering Contradiction:

ImproveeffectivenessVSAvoidstickiness

Core Design Contradiction:

ReliabilityVSObject-affected harmful factors

Solution Approach 1:

A dicarboxylic acid ester is introduced as an intermediary substance that interacts with the anticholinergic drug to reduce its stickiness. The ester acts as a mediator that modifies the physical properties of the drug formulation while preserving its therapeutic activity, thereby resolving the contradiction between effectiveness and stickiness.

Inventive Principle:

Principle #24Intermediary (Mediator)

Solution Approach 2:

The formulation utilizes parameter changes by adjusting the concentration ratios between the anticholinergic drug and dicarboxylic acid ester. By optimizing these compositional parameters, the formulation achieves high drug content (10-20 mass%) while maintaining low stickiness through the specific interaction with the ester component.

Inventive Principle:

Principle #35Parameter changes

2Reliability

If the content of anticholinergic drug is increased to improve therapeutic effectiveness, then the effectiveness in treatinghyperhidrosis is improved, but comfortableness of the preparation decreases

Engineering Contradiction:

ImproveeffectivenessVSAvoidcomfortableness

Core Design Contradiction:

ReliabilityVSEase of operation

Solution Approach 1:

The dicarboxylic acid ester serves as a comfort-enhancing intermediary that specifically targets the sensory properties of the formulation. It modifies the interaction between the drug and skin surface, reducing the unpleasant stickiness sensation while allowing high drug concentrations to maintain therapeutic effectiveness.

Inventive Principle:

Principle #24Intermediary (Mediator)

3Reliability

If a high concentration of anticholinergic drug is used to improve therapeutic effect, then the therapeutic effect is improved, but the viscosity and stickiness of the preparation increase

Engineering Contradiction:

Improvetherapeutic effectVSAvoidviscosity

Core Design Contradiction:

ReliabilityVSStability of the object's composition

Solution Approach 1:

The dicarboxylic acid ester acts as a viscosity-modifying intermediary that disrupts the molecular interactions causing high viscosity in concentrated anticholinergic formulations. By introducing this ester component, the formulation maintains high drug concentration while achieving lower, more manageable viscosity levels.

Inventive Principle:

Principle #24Intermediary (Mediator)

Data Source

PatentEP3421049B1Liquid external preparation

Publication Date: 2020.07.29 HISAMITSU PHARM CO INC

Figure 1
Figure 2
Figure 3

AI summary

The present invention provides a liquid topical preparation having low "stickiness" even when it contains a high concentration of an anticholinergic drug. The liquid topical preparation comprises water, an anticholinergic drug and dicarboxylic acid ester, and the content of the anticholinergic drug ranges from 10 mass% to 20 mass% based on the total mass of the liquid topical preparation.