Inhalable Suspensions

Inhalation is often the preferred drug delivery method for lung diseases, offering a number of advantages for both patients and medical professionals for the administration of vaccines and other biological drugs.

The active ingredient of many inhalable products, such as anti-asthma medications, acts on the muscle cells of the pulmonary airways. Such medications can be rendered inefficient, however, if particles aggregate in the inhaler. In addition, to prevent dry powder aerosols from depositing particulate matter in the oropharyngeal cavity — and in the inhaler — dispensed particles should have a geometric diameter of 1–3 µm and a mass density of approximately 1 g/cm3.

Inhaled drugs are usually dissolved in an aqueous system, such as an isotonic salt solution, and aerosolized at a high pressure to obtain nebulized particles. The liquid solution is pumped through a homogenizing valve at 500–1000 bar, using a single stage process, during which semi-solid particles become dispersed in the liquid.

The high-pressure homogenization enables the size reduction of average to large particles and makes the suspension more stable as a result of the decreased sedimentation rate. Moreover, it eliminates biological risk and provides better tolerance to irritants, as well as improving the clarity and transparency of the processed product.

In addition to a comprehensive range of homogenizers, GEA also offers production-scale mixing, blending, spray drying and micronization solutions for the manufacture of inhalable products, plus an unparalleled level of expertise in the design and layout of suitable plant: from vessel size dimensions to valves and 3D P&IDs, and from R&D to full-scale production.