Microbiological cleanliness assessment of cytotoxic compounding robot
Imperial College Healthcare NHS Trust, UK
In recent years, cytotoxic compounding robots have been marketed as a new way to prepare cytotoxic prescriptions for cancer patients. They are marketed on the basis that the process of chemotherapy compounding would be quicker, safer and more accurate. There are a number of these available on the market including Intelligent Hospital Systems RIVA™ (Robotic IV automation system) and Health Robotics Cytocare™. This talk centres on the Cytocare Unit installed at the Charing Cross Hospital in London.
The CytoCare is an enclosed “laminar” flow cabinet with an anthropomorphic robotic arm. The arm is designed to withdraw doses of cytotoxic drugs from single or multiple vials, and transfer these doses into a variety of final containers. With its complex robotics and “atypical” cleanroom machine design, determining the microbiological cleanliness / suitability for use in the compounding of cytotoxic preparations provided specific challenges.
The assessment of the microbiological cleanliness took into account the peculiar attribute of CytoCare (as operator and cleanroom) and led to the development of a two pronged approach; a direct and indirect assessment.
The direct assessment consisted of the accepted methods for evaluating the microbiological cleanliness of any clean room cabinet. This took the form of detailed post clean “environmental” (viable and non viable) monitoring. The individual elements of the viable environmental monitoring involved surface monitoring and air monitoring. Surface monitoring was achieved through the use of microbiological contact plates and surface swabs, while passive and active air monitoring was performed using microbiological settle plates and active air samplers. The non viable monitoring was performed by taking air samples and analysing their particulate content using an air particle counter.
The indirect assessment consisted of broth challenges typically used to confirm the aseptic technique proficiency of pharmacy technicians. These were process runs where routine starting materials were substituted with microbiological growth media and CytoCare put through routine production runs. The products generated were subsequently tested to determine their sterility. In addition, partially used vials which were stored in the robot for up to a day, were evaluated for sterility.
The tests demonstrated that CytoCare complied with the required EU GMP requirements for microbiological cleanliness necessary for the preparation of sterile medicinal preparations.