Schering-Plough has found success with its drug Temodar (temozolomide), which is used to treat brain tumors in adults by inhibiting the growth of cancerous cells. Temodar delivers a survival benefit to brain cancer patients an area of high unmet need in oncology. The company recently decided to transfer production of Temodar, a high-potency product, to Las Piedras, Puerto Rico.
Senior Project Engineer Jimmy Moreno knew that the Temodar move presented an engineering challenge, as it required the use of advanced isolation techniques to contain both new and existing manufacturing equipment.
Schering-Plough selected L.G. Scott, the Puerto Rico office of Lockwood Greene, Inc., to perform the design work. Since containment was such a critical issue, L.G. Scott enlisted the support of experts from the U.S., in addition to Schering-Ploughs corporate experts in isolation and process safety, and the operators who would be working on the line.
Key manufacturing equipment included small scale V-blenders, weigh scales and an oscillator. These pieces of equipment had to be arranged to maintain specific manufacturing unit operations while maintaining containment requirements. The decision was made to put the equipment into a single multi-chamber isolator. We had lots of questions, says Moreno. How are we going to clean the equipment? How can we maintain it?
In addition, an existing capsule-filling machine (encapsulator) had to be adapted to enhance dust containment and operator protection.
Schering-Plough contracted with Powder Systems Ltd. (PSL; Liverpool, U.K.) to custom-design the isolator. The team enhanced operability by placing electrical equipment drives and controls for the oscillators and V blender outside the isolator. This allows workers to operate and maintain these pieces of equipment from outside and has freed up valuable space within the isolator for operator ergonomics and easier cleaning.
The team followed a novel approach to containment of the encapsulator by exchanging the standard Perspex machine guarding with quarter-suit isolators modified protective half-suit isolators for safe, limited operator access.
The team overcame various potential safety issues for example, ensuring that gloves built into the quarter-suit isolators could not get trapped in the moving parts of the encapsulator. Given the negative pressure that builds up on the inside as the machine runs, the gloves would expand, says Monica Colberg, L.G. Scotts lead process engineer. The team placed small plexiglass doors between the gloves and the machine. The doors have interlocks that prevent the machine from running while they are open. You have a bubble and a rigid wall, like folding closet doors, Colberg explains.
This project was unique from process transfer to tech support, project control, scheduling, activities coordination, Moreno says. But it was very rewarding. The process hasnt changed, but the way its being managed is totally different because its enclosed in the isolators.
