Critical Pharmaceuticals has developed a proprietary process to encapsulate drugs into biodegradable, biocompatible polymers for controlled release applications. Competing technologies need to use elevated temperatures, organic solvents or pH changes to accomplish this, all of which can cause denaturation or degradation of the drug - particularly for delicate molecules such as proteins and peptides. This could lead to safety issues.

At a certain temperature and pressure (the "critical point") gases become "supercritical" and take on both liquid and gas like properties. By using supercritical CO₂ (scCO₂) Critical Pharmaceuticals can liquefy regulatory approved polymers in the absence of solvents and at ambient temperatures, allowing drugs to be mixed in to the polymer. In a single step, as the pressure is reduced, the scCO₂ returns to its gaseous state and leaves the polymer which solidifies around the drug. To see an animation of our process click here.

We have developed the technology so that after the polymer is liquefied and the drug mixed in, we can form:

MICROPARTICLES	IMPLANTS	FIBROUS MATERIALS
Sustained release injections (weeks to months)	Sustained release injections (several months)	Drug delivery into cavities.

Each of these morphologies can contain encapsulated drug, whose release can be easily tailored to the specific application. Using the technology we can process a wide range of regulatory approved polymers into these morphologies (e.g. PLGA, PLA, poloxamers, PEG).

The advantages of our process are:

• There is no chemical modification of the drug:
  • Shorter clinical trials process e.g. compared to PEGylation.
  • We can make enhanced formulations as part of a product lifecycle management strategy.
  • Drug activity, stability, safety and distribution in the body is unchanged.
• The process operates at ambient temperatures, allowing temperature sensitive molecules such as proteins and peptides to be encapsulated without any degradation.
• 100% of the drug activity is maintained.
• It is entirely solvent free so there are no solvent residue concerns, and saving the financial and environmental costs associated with solvent disposal.
• It is a one step process with 100% encapsulation efficiency.
• We can maintain therapeutic plasma levels for weeks to months following a single injection.
• Our process is protected by a family of patents.