Phase-Inversion In Situ Systems: Problems and Prospects of Biomedical Application

Area of Science:

• Pharmaceutical Science
• Biomaterials Science
• Drug Delivery Systems

Background:

• Stimuli-sensitive (in situ) drug delivery systems are rapidly advancing, with research doubling in the past decade.
• Phase-inversion (phase-sensitive) formulations, though early concepts, offer significant advantages like enhanced stability and stimuli-responsiveness.
• Despite patented technologies, phase-inversion systems remain understudied due to a lack of unified development and standardization approaches.

Purpose of the Study:

• To review polymers and solvents used in phase-inversion compositions.
• To explore the potential of incorporating additional excipients to tailor physicochemical properties.
• To identify challenges and propose recommendations for the clinical adoption of phase-inversion drug delivery systems.

Main Methods:

• Comprehensive literature review of phase-inversion systems.
• Analysis of clinical studies (past 25 years) and indexed research (PubMed, ScienceDirect, Google Scholar).
• Examination of commonly used polymers (polylactide-co-glycolide, shellac, polylactic acid) and solvents (N-methylpyrrolidone, dimethyl sulfoxide).

Main Results:

• Polylactide-co-glycolide, shellac, and polylactic acid are key polymers; N-methylpyrrolidone and dimethyl sulfoxide are prevalent solvents.
• Lack of standardized development protocols significantly hinders clinical translation of novel phase-inversion drugs.
• Identified key issues impeding broader clinical application of these advanced drug delivery systems.

Conclusions:

• Phase-inversion systems represent a promising avenue for stimuli-sensitive drug delivery.
• Standardization and further research into excipient compatibility are crucial for overcoming current limitations.
• Recommendations are provided to guide future development and facilitate clinical implementation.