Plexis consists of high–drug-loading (>90%) active pharmaceutical ingredient (API) microparticles coated with a thin, biocompatible polymer membrane that governs diffusion-controlled release. The system includes (i) size-controlled drug cores, (ii) a laminated polymer coating that enables tunable release kinetics, and (iii) an aqueous suspension vehicle optimized for syringeability and subcutaneous injection. Release rate is adjusted by particle size distribution and membrane properties rather than polymer degradation.

Raw materials include the API, pharmacopeia-grade polymer excipients (e.g., USP/NF polymers), standard crosslinking agents, and aqueous suspension excipients. All materials are commercially available from multiple qualified suppliers with established GMP supply chains. No rare or constrained materials are required. Costs are comparable to conventional injectable excipients; the primary cost driver remains the API. The platform is compatible with scalable, cost-effective manufacturing and is not dependent on cold-chain–specific materials.

No delivery device

Plexis is well suited for scale-up using standard pharmaceutical unit operations. The manufacturing process relies on controllable particle sizing and membrane coating steps that are scalable by increasing batch size or equipment capacity rather than altering formulation fundamentals. The platform has been successfully produced at laboratory and pilot scales, with a clear path to GMP clinical and commercial manufacturing.

Key equipment includes particle size reduction and classification tools (mills, sieves), fluidized-bed or spray-based coating systems, standard mixing vessels for suspension preparation, filtration and drying equipment, and conventional sterile fill–finish systems. No highly specialized or custom-built equipment is required, enabling technology transfer to multiple CMOs.

Manufacturing can be performed in standard GMP pharmaceutical facilities with controlled environments appropriate for sterile injectable products. No extreme temperature, pressure, or environmental conditions are required. The process is compatible with common solvent handling and recovery practices, standard cleaning validation, and established quality systems for parenteral drug products.

Formulation characterization relies on standard analytical tools, including HPLC/UPLC for assay and impurities, particle size analysis (e.g., laser diffraction), microscopy/SEM for morphology, in vitro release testing apparatus, and routine physicochemical tests (pH, viscosity). No bespoke analytical platforms are required beyond those commonly available in pharmaceutical QC laboratories.

No proprietary excipient used

No novel excipient or existing excipient used

Organic solvents may be used transiently during manufacturing (e.g., during coating or processing steps), but they are removed during downstream processing. Residual solvent levels in the final drug product are controlled and tested to meet ICH Q3C limits and applicable regulatory requirements.

• Biodegradable
• Drug-eluting
• Room temperature storage
• At least 1 year shelf life

Plexis provides sustained, diffusion-controlled drug release via high–drug-loading (>90%) microparticles coated with a thin, biocompatible polymer membrane. Release kinetics are smooth and predictable, with reduced burst and variability compared to degradation-based depots, and can be tuned by particle size and membrane properties to support monthly or longer dosing intervals.

Plexis formulations are designed for subcutaneous administration using small-gauge needles and clinically practical injection volumes. High drug loading enables lower injection volumes relative to conventional polymer depots, supporting improved syringeability, patient comfort, and use in outpatient and chronic care settings.

The Plexis platform uses biocompatible materials with prior regulatory acceptance. Safety and local tolerability have been demonstrated in preclinical studies and in Phase I and Phase IIb clinical trials across multiple molecules, with favorable injection-site histopathology and no unexpected safety signals attributable to the delivery system.

Plexis formulations demonstrate robust physical and chemical stability, supported by ongoing and completed stability studies. The diffusion-based release mechanism is not dependent on polymer degradation, contributing to consistent performance over time and enabling extended shelf life under controlled room-temperature conditions.

Plexis drug products are designed for room-temperature stability, eliminating the need for cold-chain storage. This simplifies distribution, reduces logistical complexity and cost, and improves accessibility in outpatient, community, and resource-limited healthcare settings.