Invitrogen and Qualyst this week announced that they have entered into a co-exclusive agreement to offer hepatocyte-screening services and research products to the pharmaceutical community.
Under the terms of the agreement, Invitrogen’s wholly owned subsidiary CellzDirect will provide in-house drug-metabolism and transport-screening services, as well as commercialized kits that combine Qualyst’s B-Clear technology and CellzDirect’s cell products.
To Qualyst, the deal enables it to accelerate the adoption of B-Clear across the drug discovery and drug development industry, according to a company official.
Financial details of the agreement were not disclosed.
The hepatocyte-testing service will be available by mid-December, and the kits will be available for purchase early next year, Invitrogen said. All B-Clear products and services will continue to be available from Qualyst.
“We have long worked with CellzDirect and are excited to expand our relationship and accelerate the adoption of B-Clear across the drug discovery and development industry,” Qualyst CEO Marc Sedam said in a statement. “Drug transporter-based research is expanding dramatically, and we believe working with CellzDirect will provide industry leadership in this area.”
Chris Black, senior director of hepatic operations for CellzDirect, told CBA News this week via e-mail that Invitrogen does not release data covering the potential size of the hepatocyte-testing service or kits markets, though he said the company believes hepatocyte testing is a growth area.
“CellzDirect has had a longstanding link with its scientists and Qualyst's scientists back to the University of North Carolina at Chapel Hill to when the B-Clear patent was filed,” said Black. Since that time, he said, CellzDirect has been a supplier for Qualyst, and has been interested in the B-Clear technology.
Being Clear About In Vivo Predictivity
B-Clear is a patented, sandwich-cultured hepatocyte system, and Qualyst claims that it is the only in vitro method to predict in vivo hepatic uptake and biliary clearance, and assess drug transporter inhibition.
B-Clear maintains hepatocytes in culture between two layers of gelled collagen, which results in the formation of extensive, functional canalicular networks. In vitro biliary clearance is calculated by differentiating between the total amount of a compound taken up into hepatocytes, and the total amount of a compound that is taken up and excreted into the canalicular networks.
The networks are composed of so-called “bile pockets” that are excluded from the media by tight junctions between cells. The media contain calcium in order to maintain the tight junctions sealing the bile pockets.
Incubation in calcium-deficient media causes the tight junctions to open and release the contents of the bile pockets into the media, which in turn permits researchers to quantitate the amount of a compound that has accumulated in the hepatocytes.
Qualyst said it has validated the B-Clear system, including assessing the expression of hepatic uptake and excretory transporters, localization of the transporters to the correct membrane in the hepatocyte, and the proper function of those transporters.
Also, evaluating control compounds in each experiment has demonstrated high reproducibility and low variability, and probe substrates using B-Clear have demonstrated in vitro to in vivo biliary clearance correlation for both rats and humans, the company said.
The company sells B-Clear kits with either rat or human hepatocytes.
Sedam told CBA News in an e-mail this week that customers for B-Clear products and services “run the gamut” from top-20 pharmas to smaller biotechs. He also said that B-Clear is appropriate for any company interested in knowing how their compounds behave in the liver, including cellular accumulation, as well as the potential for transporter-based drug-drug interactions.