By Mary Welch

Bolstered by a $7.25 million financing round, FeRx Inc. said it will begin Phase I/II trials with its lead product, based on magnetic targeted carrier (MTC) drug-delivery technology, as early a next month.

"The money should last us into 2000," said Jacqueline Johnson, president and CEO of San Diego-based FeRx. Funding came from several private investors, as well as $3.5 million from Brentwood Venture Capital, of Los Angeles. A financing round in 1997 yielded almost $3.5 million for the firm, which began three years ago with $1 million in seed capital.

FeRx began in Russia. One of the company's three founders, Thomas Kent, went to the former Soviet Union after the breakup looking for interesting technology unknown in the West. Kent is a co-founder of Medical Electronics Corp. of America, in Denver, which manufactures microwave hyperthermia equipment for cancer therapy. In Moscow, he came across a trio who had invented a magnetic carrier they were using in patients. Kent obtained the technology licenses and later assigned those rights to FeRx.

When he returned to the U.S., Kent researched targeted drug delivery systems, which is how he met Kenneth Widder, a scientist who held some of the earliest patents in the field. Widder, chairman of the Regional Technology Alliance of San Diego and former CEO and chairman of Molecular Biosystems, also of San Diego, joined Kent. The two then teamed up with Johnson, experienced in running start-up and early-stage biotechnology companies, and FeRx was formed.

Their collective talents work like those of the Russians met by Kent, Johnson said.

"The three in Russia consisted of an engineer, an oncologist and a specialist in biomaterials," she said. "That's what was so different from how things are done here. You tend not to get that mix of distinct sciences working together."

The company has already obtained three patents to the technology in the U.S. (worldwide patent licensing is pending) and set up a "semi-virtual" company. "We have about 17 employees and a 7,500-square-foot manufacturing plant in Arvada, Colo., near Denver," Johnson said. "Our investigational new drug application has cleared, and we're far enough along to start Phase I/II trials in late November."

These trials will involve using the MTC technology with the generic anti-tumor drug doxorubicin for treatment of patients with primary liver cancer. Preclinical studies were completed in collaboration with the department of radiological sciences at the University of California at Los Angeles, where imaging studies were undertaken to show targeting and retention of MTCs in pigs. Pigs were chosen because they are large, which allows the testing of the magnetic field strength to depths of approximately 10 to 13 centimeters.

MTCs are microparticles composed of elemental iron and activated carbon, and serve as the delivery vehicle for site-specific targeting, retention and sustained release of drugs. Elemental iron is highly magnetic, and the activated carbon component provides carrying capacity for drugs and biomolecules.

The technology works by using a small external magnet to create a localized magnetic field within the body. Drugs are adsorbed to MTCs and administered intra-arterially. The force created by the magnetic field induces the carrying of the MTCs through the vascular wall, which leads to the localization and retention of particles at the desired sites.

Once it arrives at those sites, the drug is desorbed over a period of several hours to several days.

The advantages are many, Johnson said. MTCs may significantly lower the overall dosage of drugs while still achieving the needed concentration in the body. They may also limit side effects caused by non-specific systemic exposure.

"This system doesn't depend on any specific receptor or cell type responding to the drug," Johnson said. "It's not a biological reaction. It's a physical force, if you will, at the disease site. It also can go deep into the tumor."

MTCs have the potential to bind to a variety of therapeutic compounds, including anticancer drugs, biologics and nucleic acids. "For us, the most obvious indication is cancer, because you can do smaller trials and there are a variety of generic drugs available," Johnson said. "There is the potential of being fast-tracked by the FDA, which certainly would help."

Although FeRx has particular experience in binding of small molecules, biologics and nucleic acids to MTCs, other drug classes that potentially benefit from the localized delivery system include imunosuppressants, antibiotics, thrombolytics, anti-inflammatories, genes and steroids, Johnson said. *

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