A Reflection of Biotech Itself
Cell culture media and production capacity are closely interdependent. Some experts, like Professor Florian Wurm at the Swiss Federal Institute of Technology, believe that media have been responsible for most of the recent rise in protein titers and volumetric productivity. Higher titers mean smaller reactor volumes or fewer batches, which explains why growth in demand for cell culture media is slowing somewhat. “But while less is needed, media tend to be richer,” says Bruce Lehr, marketing director at SAFC Biosciences.
Instead of using more concentrated media formulations, bioprocessors begin with simpler media and supplement it with highly concentrated feeds during growth and production phases. Because production cells have been engineered to utilize nutrients more efficiently, somewhat fewer ingredients are employed today per production unit than years ago.
The evolution of cell culture media reflects the maturity of bioprocessing and biotech itself. “Fifteen years ago, companies were worried about getting product to market. Today, they’re more concerned with streamlining processes, lowering costs, and supply chain management,” says Lehr.
Chemically defined media and to a lesser degree ACF media play into the trends of process streamlining, simplification, and standardization with the goals of predictability and consistency. The platform idea that has worked so well with cells and unit operations has become attractive for processes as well.
Media optimization appears to be at odds with one-medium-fits-all standardization, but it actually is not because standard media have become so good. SAFC, for example, offers 14 chemically defined formulations in its CHO Media Library. Processors can try several of these for their specific cells, or begin with the CHO Fusion Media formulation, which SAFC claims provides the highest growth and productivity across the widest range of clones.
“If you had to try one medium, this is the one formula we’d recommend,” Lehr says. “It does not replace media optimization, but it does offer an alternative to full-blown optimization for customers who don’t have time, money, or expertise to optimize their own system.” Lehr points out that most large biotech companies optimize in-house.
SAFC plans to introduce a chemically defined CHO feed supplement to replace hydrolysates early in 2009.