An HPAPI is a Highly Potent Active Pharmaceutical Ingredient and can be defined as a pharmaceutical compound with a low Occupational Exposure Limit. The occupational exposure limit defines the maximum quantity of product an operator can be exposed to within a defined time frame to avoid the risk of short and long term effects on his or her health. The OEL of each pharmaceutical compound is defined by toxicologists through laboratory studies.
A specific value of 10µg/m3 is defined as the threshold limit for the definition of an HPAPI. All compounds with a lower OEL are considered highly potent.
As the risk of an adverse effect on human health is the product of a hazard and the exposure to such hazard, risk mitigation of handling potent APIs (high hazard) can only be accomplished through the adoption of containment systems (low exposure).
Human body can assimilate drugs in different ways: by inhalation, skin absorption, ingestion or injection. Of these, inhalation is the most common in pharmaceutical manufacturing hence it is the one that requires most countermeasures.
Containment systems such as downflow booths, pack-off stations or isolators are designed to create a physical or an aerodynamic barrier between operators and product. Once the OEL is defined, the choice of the proper technology is based on multiple factors, including for example dustiness potential of the product, task duration and quantities involved.
On the vendor side, the design of a containment solution is carried out with the goal of achieving a defined CPT, Containment Performance Target, that is assessed through a SMEPAC test carried out after the on-site installation of the equipment.