Controlled Drug Delivery Systems Utilizing Biodegradable Polymers

Controlled drug delivery systems based on biodegradable polymers represent a transformative approach to therapeutics by offering precise spatio-temporal control over drug release, reducing dosing frequency and minimising systemic side effects. These systems typically harness aliphatic polyesters such as poly(lactic-co-glycolic acid) (PLGA), poly(lactic acid) (PLA) and emerging copolymers like polybutylene adipate co-terephthalate (PBAT) blended with hydrophilic excipients (for example polyvinylpyrrolidone) to tailor degradation profiles and drug-loading capacity. Formulation techniques encompass emulsion-solvent evaporation, microfluidics, electrospray and supercritical fluid processes to produce micro- and nanoparticles, hollow microspheres or injectable depots. Recent advances integrate machine learning and quality-by-design frameworks to predict release kinetics and streamline formulation development. Key challenges remain in achieving high encapsulation efficiencies for hydrophilic compounds, mitigating initial burst release and ensuring batch-to-batch reproducibility under scalable manufacturing conditions. Translation to clinical practice has been exemplified by long-acting injectable depots for peptides and small-molecule drugs, with enhancements in patient compliance, therapeutic index and global access to sustained-release therapies.

Research from Nature Portfolio

Recent studies have demonstrated the power of data-driven approaches to accelerate the design of polymeric long-acting injectables. By training machine learning models on a broad dataset of formulation parameters and release profiles, researchers have achieved high-accuracy predictions of drug liberation from biodegradable microspheres. This framework not only reduces reliance on iterative in vitro testing but also identifies optimal polymer compositions and process conditions for bespoke release schedules, paving the way for more efficient and cost-effective development of sustained-release therapeutics.

Controlled Drug Delivery Systems Utilizing Biodegradable Polymers publication trend

The graph below shows the total number of articles in controlled drug delivery systems utilizing biodegradable polymers across all publications each year (not limited to Nature Index journals).

Technical terms

Biodegradable polymer: A macromolecule that undergoes hydrolytic or enzymatic breakdown into non-toxic byproducts within the body.

Long-acting injectable (LAI): A formulation designed for intramuscular or subcutaneous administration that releases active drug over an extended period, typically weeks to months.

Microsphere: A spherical microparticle, often composed of biodegradable polymer, serving as a reservoir for controlled drug delivery.

Emulsion-solvent evaporation: A technique in which polymer and drug dissolved in volatile organic solvent are emulsified in an aqueous phase, followed by solvent removal to form solid particles.

Machine learning algorithm: A computational method that identifies patterns in data to predict outcomes, here used to forecast drug release kinetics from polymeric carriers.

References

1. Machine learning models to accelerate the design of polymeric long-acting injectables. Nature Communications (2023).
2. Fabrication of biodegradable hollow microsphere composites made of polybutylene adipate co-terephthalate/polyvinylpyrrolidone for drug delivery and sustained release. Materials Today Bio (2023).
3. Poly(lactic-co-glycolic acid) microsphere production based on quality by design: a review. Drug Delivery (2021).