Esketamine Microsphere Formulation for Extended Injectable Release

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Solution Overview

Problem

Existing ketamine formulations require frequent patient visits for administration, causing inconvenience and potential diversion, while maintaining effective treatment for depression and chronic pain.

Innovation Solution

Development of microsphere formulations containing esketamine encapsulated in biodegradable polymer microspheres, specifically designed for extended release over 30 days, allowing less frequent administration and reducing the need for multiple visits.

Engineering Contradictions & Design Principles

VSEngineering Contradiction Analysis

1Reliability

If ketamine is administered as immediate-acting injection, then therapeutic efficacy is achieved, but frequent patient visits are required causing inconvenience and potential diversion

Engineering Contradiction:

Improvetherapeutic efficacyVSAvoidpatient convenience

Core Design Contradiction:

ReliabilityVSEase of operation

Solution Approach 1:

The patent segments the drug delivery system into microsphere particles containing ketamine, which are then formulated into an injectable suspension. This segmentation allows the drug to be released gradually from multiple particles over time, extending the duration of action from immediate to sustained release over weeks or months, thereby reducing the frequency of administration while maintaining therapeutic efficacy

Inventive Principle:

Principle #1Segmentation

Solution Approach 2:

The patent applies preliminary action by pre-encapsulating ketamine in biodegradable polymer microspheres before administration. The microspheres are designed to degrade at a controlled rate, releasing the drug over an extended period. This preliminary preparation eliminates the need for frequent re-administration, as a single injection provides sustained therapeutic levels of ketamine

Inventive Principle:

Principle #10Preliminary action

2Reliability

If ketamine is administered as immediate-acting injection, then therapeutic efficacy is achieved, but potential diversion and abuse occur

Engineering Contradiction:

Improvetherapeutic efficacyVSAvoiddiversion and abuse

Core Design Contradiction:

ReliabilityVSObject-affected harmful factors

Solution Approach 1:

Inventive Principle:

Principle #10Preliminary action

Solution Approach 2:

The biodegradable polymer microspheres serve as an intermediary between the ketamine drug and the patient's body. This intermediary controls the release kinetics of ketamine, preventing abrupt high concentrations that could lead to abuse, while maintaining therapeutic levels over time. The polymer matrix acts as a rate-limiting barrier that mediates drug delivery

Inventive Principle:

Principle #24Intermediary (Mediator)

3Ease of operation

If microsphere formulations are developed for extended release, then patient visits are reduced, but formulation complexity increases

Engineering Contradiction:

Improvepatient convenienceVSAvoidformulation complexity

Core Design Contradiction:

Ease of operationVSDevice complexity

Solution Approach 1:

The patent utilizes parameter changes by varying the polymer composition, molecular weight, and crosslinking density of the biodegradable microspheres to control drug release kinetics. By adjusting these parameters, the formulation achieves extended release profiles (from weeks to months) without requiring complex delivery devices or mechanisms, maintaining relative simplicity in the administration process

Inventive Principle:

Principle #35Parameter changes

Solution Approach 2:

The patent employs composite materials by combining ketamine with biodegradable polymers (such as PLGA, PLA, or chitosan) to create microspheres with tailored release properties. The composite structure allows control over drug release rate through polymer selection and formulation parameters, achieving extended release functionality while keeping the overall system relatively simple for clinical administration

Inventive Principle:

Principle #40Composite materials

Applied Scientific Principles

This section explains which scientific principles are used to turn an abstract innovation direction into a practical engineering solution.

Function Achieved in This Case

The microsphere formulations provide a convenient and controlled release of esketamine, reducing patient burden and potential diversion, while maintaining therapeutic efficacy for depression and chronic pain treatment.

Implementation Method 1

polymer microspheres, each polymer microsphere comprising: (i) esketamine; and (ii) a biodegradable poly(lactide) ('PLA') polymer

Methodology Applied

Scientific EffectBiodegradation: Decomposition (biological)

Implementation Method 2

A method for making double-emulsified polymer microspheres is provided, the method comprising: (i) contacting esketamine with a biodegradable PLA polymer in the presence of a solvent to form an organic component and providing the organic component to a first homogenizer; (ii) providing an inner aqueous component comprising water and a first surfactant to the first homogenizer; (iii) homogenizing the organic component with the inner aqueous component to form a primary emulsion

Methodology Applied

Scientific EffectEmulsion: Emulsion

Data Source

PatentEP4199917B1Microsphere formulations comprising ketamine and methods for making and using the same

Publication Date: 2026.01.07 OAKWOOD LABORATORIES LLC

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AI summary

Extended-release, injectable microsphere formulations comprising ketamine are provided. Methods for making and using the microsphere formulations are also provided.