Whether the new production process approved by the US Food and Drug Administration (FDA) last week is “continuous" or not is a matter of debate.
According to Janssen and co-developers Rutgers University it is definitely a continuous process that cuts the time needed to make Prezista (darunavir) by 80%, reduces waste 33% and shaves 20 days off release testing.
The FDA also says it is continuous.
In a blog post last week the agency said its decision to let Janssen make Prezista using the new method was the first time it has allowed a firm to change “from batch to continuous manufacturing.”
Batch
Others, like Epcot International president Girish Malhotra, are not convinced.
He suggested Janssen is “calling an ugly duckling a swan” arguing that the firm has simply developed a more efficient batch process that does not meet the classical definition of a continuous process.
Malhotra asked us “Is the operation running 24 hours a day, seven days a week and 50 weeks a year with about 15% planned downtime? If it is not then, according to the chemical engineering definition, it is not a continuous process.”
Inventory
We put these comments to Janssen spokesman Craig Stoltz, who told us “while continuous manufacturing (CM) can be defined in various ways, we don’t believe it needs to be a 24-hour, seven-day, 50-week-a-year process.
“Our definition of CM, and the way we believe it is defined by others in the industry, is focused on moving from process-step to process-step without intermediate waiting in between.”
He also said that Janssen would not run its process for longer than it needs.
“One of the benefits of continuous manufacturing is that it allows us to run only long enough to make the volume of product needed. As a result, we are able to reduce overall inventory, track demand and produce additional supply based on market need.”