Advanced Magnetics considers ultrasound contrast agent market

Advanced Magnetics is best known for developing contrast media designed for use with MRI scanners, but the Cambridge, MA, company sees potential outside the MRI market. Advanced Magnetics reported this month that it has entered an option agreement to purchase rights to ultrasound contrast technology developed by Cavitation Control Technology (Cav-Con).

Cav-Con has developed contrast technology that employs microbubbles coated with lipids. This agent, called Filmix, is designed with a special affinity for a variety of cancers, including those of the breast, prostate, and liver. When used as a diagnostic agent, the microbubbles enhance ultrasound images, and could also serve double duty as a therapeutic agent: When injected full of toxin, they could deliver a lethal dose to the cancer.

"It would be useful in therapy as well as diagnostics, assuming that you load these microbubbles up with a drug, and, given the way it is made, that should be possible," said Jerome Goldstein, chairman and CEO of Advanced Magnetics. "That's the promise. The reality has to be ascertained."

Cav-Con is a privately held company in Farmington, CT, and so far has conducted only in vitro and animal tests of Filmix. Those tests, however, have been very encouraging, according to Dr. Michael Davis, a professor of radiology and director of radiologic research at the University of Massachusetts in Worcester.

Davis ran some of the tests on Filmix, documenting its attraction to cancers. Davis was also the matchmaker who put Cav-Con and Advanced Magnetics together. Criteria for making the match included the ability to react quickly to opportunities and an interest in agents that could serve both diagnostic and therapeutic purposes. Advanced Magnetics fit both criteria.

"We've spent a great deal of money already developing targeted drug delivery systems," said Goldstein, referring particularly to drug targeting technologies that address liver cancer. Microbubbles are also focused on cancer, but their development is a long way from market.

To capitalize on the potential of Filmix, Cav-Con will have to scale up its manufacturing operation. Davis said that the company so far has made batches of only about 100 vials at a time. Then there are the actual clinical trials.

"It has never been put in a patient," Davis said. "There has been both small and large animal work, which looks very positive, but until you actually do the first patient trial and show efficacy, you never know. There can be species differences and it may not work."

Davis and his colleagues at the University of Massachusetts would probably do some of the early clinical studies. Advanced Magnetics will then likely organize a large multicenter pivotal study, Davis said.

Those actions are still pending a decision by Advanced Magnetics on whether to exercise its option and formalize the deal with Cav-Con. Goldstein said that the current agreement provides his company only with an option to obtain development and marketing rights.

"The decision whether to exercise the option will come in a fairly short period of time," he said. "It's just that we don't want to find any skeletons in the closet."