MeriCal, which is based in Anaheim, CA, is a dry dosage form dietary supplement contract manufacturer specializing in probiotics. Jeremy Bartos, PhD, senior vice president of research and development of Merical, spoke with NutraIngredients-USA about the process.
The major difficulty, Bartos said, is that USP has not verified a probiotic before, so some procedures had to be developed from the ground up.
“It took about three years of hard work to get to the point of verification,” Bartos said. “We were helping to establish a USP protocol for testing a probiotic.”
Building a process for multi-strain products
A big complicating factor was the fact that the two products that have been verified are multi-strain products. One contains 10 strains and the other 12, Bartos said. The products are being sold by Costco and Sam’s Club.
“At the time we started with this process there are no USP monographs written for any of the raw material probiotic strains,” he said.
“One of the most onerous parts of the process was to establish parameters for both the strains and the finished products,” Bartos added.
Bartos said Merical worked with its probiotic raw material supplier to develop testing methodologies for each strain. This involved identifying SNP primers specific to each strain. Using those tools, tests could then be developed and verified to identify those strains on the input side as well as their presence in the finished product.
What hasn’t been done yet, Bartos said, is to develop a method to quantify individual strains within a multi-strain blend. MeriCal has verified a way to state that if it lists 10 billion CFUs on the label, there will be 10 billion CFUs in there. But no method yet exists to say that there are 1.5 billion viable CFUs of strain A, 1 billion of strain B and so forth. That speaks to some of the continuing limitations of a DNA-based approach.
“The complication is that a strain can contribute DNA whether it’s viable or whether it’s dead,” Bartos said.
“The technology is not there yet to do that. There are a couple of companies working on technologies to solve that problem,” he said.
Another part of the verification process was to determine with precision the amount of overages required to meet label claim at the end of shelf life. The lengthy stability testing was a big part of the reason why the verification process stretched into years, Bartos said.
Bartos said he believes however onerous the USP verification process was, it will ultimately be worth it. Many health care practitioners are still wary of products that claim to be adding live microorganisms to the system. But he said many consumers are clamoring for this information and as matters stood, pharmacists and doctors had little way to determine which products were the highest quality and would perform the best for their patients.
“The USP verification process forces you to make sure you have all of your ducks in a row. Not just on ingredients, but on packaging and everything else. The easiest thing for us would have been to do this verification on a single strain product, but multi-strain products is the direction we have seen the market going in,” he said.
“The USP seal gives an important differentiation for physicians and pharmacists to understand and recognize. They already know the USP seal very well from the pharmaceutical side,” Bartos added.