Making the Right Choice
“I’ve seen companies embrace disposables much more over the past five years, and a lot of the excitement has to do with the available disposable sensor technology, which eliminates many previous limitations,” says Craig Sandstrom, Ph.D., director of process engineering for Fluor (www.fluor.com). Dr. Sandstrom has completed several case studies of facilities designed around trying to implement disposables.
“You have to adopt the technology early on because it affects the facility layout. Disposable bags increase material handling and material flow issues and should be in a facility on one level versus a traditional biomanufacturing facility, which is multilevel.”
Dr. Sandstrom is surprised that many people expect disposables to reduce facility costs by up to 80%. “Everybody is in shock when they discover that this isn’t the case. There are a lot of facility costs involved with disposables that you can’t reduce—you’re only saving about 10 to 20 percent.” In addition, he says, the overall facility footprint is larger with portable equipment.
Deciding whether to use disposables or stainless steel often depends on the automation requirements of the facility. Overall, disposables are more labor-intensive and less automated than stainless steel systems. Every case has to be examined individually, Dr. Sandstrom says, but often disposables provide more flexibility for faster construction renovation.
Virxsys (www.virxsys.com) is currently conducting Phase II trials in HIV patients using lentiviral vectors for gene therapy. After the Phase I trial was completed, the company realized it would need to manufacture enough cells to administer multiple infusions, requiring a change to its manufacturing process.
“We have to grow large concentrations of cells, but this needs to be done from individual patients. We needed something efficient and manageable that could be scaled up,” explains Gerard McGarrity, Ph.D., vp, scientific and clinical affairs.
The company decided to use the Wave Bioreactor® and Cellbags® from GE Healthcare (www.wavebiotech.com), which, Dr. McGarrity reports, eliminate cleaning and validation and can be installed rapidly.
“The basic challenge was optimization. We were familiar with the products, but everything had to be optimized. It was an innovative process in that this was the first time the lentiviral vector was administered to human patients,” adds Dr. McGarrity.
The company decided to use disposables since it is treating individual patients with ex vivo gene therapy. “We didn’t want hardware we had to clean and recertify for each patient. Also, the disposables allow for processing several patients’ cells simultaneously.” However, Dr. McGarrity explains, disposables require more vigorous training since they involve more handling. Yet, for small- and medium-sized biotech companies, he agrees that disposables are an attractive option for cell expansion.