Process-friendly technology inactivates prions on critical healthcare, pharmaceutical surfaces
11/01/2004
BY STEVE SMITH
MENTOR, Ohio — Anti-prion processes developed by STERIS Corp. (www.steris.com) have been found to inactivate deadly prions that can lead to fatal illnesses in humans and animals.
Prions are believed to be the causative agent of a group of fatal animal and human diseases, known as Transmissible Spongiform Encephalopathy (TSE), that affect the central nervous system and include Mad Cow Disease. Prion proteins have proven extremely difficult to inactivate from the surfaces of surgical instruments or pharmaceutical manufacturing surfaces. But according to a study published in the August 7 edition of The Lancet, an international journal of medical science and practice, the STERIS technologies can significantly reduce the risk of the spread of such prion-associated infirmities from contaminated surfaces.
"Until now, the most widely promoted prion-inactivating technologies included harsh and/or impractical conditions, such as exposure to 10,000 ppm bleach or 1N NaOH for up to one hour, or autoclaving at extreme temperatures and contact times," says Elaine Kopis Sartain, director/technical services of STERIS' Life Sciences division. "These processes are not only time-consuming but also may lead to unacceptable damage to surfaces used in pharmaceutical processing equipment."
STERIS' prion inactivation technology, notes Kopis Sartain, "offers proven compatibility with the most commonly used pharmaceutical construction materials, and a reasonable contact time requirement (15 minutes)."
Focusing on the United Kingdom, which has been particularly hard hit by Mad Cow Disease, STERIS' healthcare segment has introduced Hamo 100 PID (Prion Inactivation Detergent)—a low-foaming alkaline detergent that can be used in such automated applications as clean-in-place systems and automated washers used for cleaning surgical instruments. While it is compatible with such surfaces as 316-stainless steel and EPDM (Ethylene Propylene Diene Monomer) rubber, Hamo 100 PID is not intended for manual applications in concentrations of greater than one percent.
"There's a great deal of concern by both biotechnology manufacturers and healthcare providers in the U.K. that not only materials of bovine origin but also possibly human blood may be a source of prions at unacceptably high risk levels," says Kopis Sartain. "This puts healthcare providers in a position where they are looking for non-destructive means of adequately decontaminating their surgical instruments."
Although there are similar concerns in the U.S. market, says Kopis Sartain, a combination of market need and regulatory pathways prompted STERIS to release this technology to the U.K. first.
At home, meanwhile, the Life Sciences segment of STERIS is planning to re-introduce its CIP-100 cleaning solution as one that, according to published research, has also been proven effective against prions. CIP-100 is an established solution used to clean pharmaceutical and biotechnology production equipment, but since the EPA has determined that prions are considered pests and thus fall under their jurisdiction, CIP-100 cannot be promoted specifically for prion applications without first receiving EPA approval.
"STERIS is working with the EPA to establish the necessary pathway in order to establish label claims for CIP-100 against prions," says Kopis Sartain. "As this type of claim is unprecedented, we cannot say when such a claim structure will be in place."
Once the claims have been established with the EPA, however, STERIS is hopeful that CIP-100 will attract those who are currently using harsher or less effective prion-fighting technologies.
The proprietary formulations for both CIP-100 and Hamo 100 PID combine an alkaline base with a strong detergent system that includes surfactants, all of which add a number of different mechanisms—e.g., solubilization, dispersion, and emulsification—to the cleaning process.
"The benefits of these multiple mechanisms," says Kopis Sartain, "is that cleaning of tough soils and molecules can occur at lower concentrations and contact times than one may find with non-formulated or commodity chemical agents."