FeRx Inc. stopped enrollment in a worldwide Phase II/III trial of its lead cancer drug, leaving the company vulnerable to a potential shutdown of operations.

The clinical trial, which was evaluating FeRx's MTC-DOX - which combines its drug delivery system MagneTarg with doxorubicin - in patients with primary liver cancer, failed to meet its primary endpoint in an interim analysis.

"We looked at the data that we had available to us and determined that we weren't going to be able to meet the endpoint," said Todd Myers, chief financial officer of San Diego-based FeRx. "We were definitely surprised. We're disappointed, but we're looking at what our alternatives are and we're going from there."

The multicenter trial was designed to enroll 240 patients at clinical sites in North America, Europe and Asia. The company aimed to find a clinically and statistically significant increase in median survival time for patients treated with MTC-DOX compared with patients receiving an intravenous form of doxorubicin.

While MTC-DOX did not meet its primary endpoint, FeRx is hoping to stay afloat by partnering the technology or product. It also would consider merging with another company.

"I don't think we want to cast aside anything that might be in front of us," Myers told BioWorld Today. "We think there is still some value to the company and we're exploring what alternatives there might be to bring that value to fruition."

The company, which was founded in 1997, also nixed plans for a venture capital financing that was in the works. FeRx is working to secure another financing, but is considering as a last resort closing its facilities. The private company has 40 employees.

Since inception, the company has raised $60 million. It last raised $15 million in its third round conducted in 2002 to pay for the Phase II/III trial of MTC-DOX. At that time, the company anticipated a new drug application filing later this year. (See BioWorld Today, June 7, 2002.)

Myers declined to say how many months the company's current cash reserves will carry it.

"We definitely need significant financing to really take this all the way through," he said. "We're evaluating right now what we're going to be able to manage the burn rate at."

FeRx's platform technology, the MagneTarg drug delivery system, has been designed to have applications across a range of therapeutic areas and to provide a technology platform for targeted delivery of small molecules, radionuclides, biologics and genetic vectors. Initially, FeRx focused on using MagneTarg for the treatment of certain solid tumors.

In addition to its MTC-DOX product, MagneTarg would be used to deliver FeRx's second candidate, MTC-MMC, a mitomycin C product to treat non-small-cell lung cancer. The FDA approved an investigational new drug application in December, and FeRx would begin studies upon closing a financing.

As for MTC-DOX, the product is not dead, Myers said.

"We think that there might be a way to do something slightly different with the manufacturing process to make that a viable product again," he said.

MTC-DOX has been studied in the Phase II/III primary liver cancer trial, as well as in a Phase I/II metastatic liver cancer trial. It is a magnetic targeted carrier technology delivering the anticancer drug doxorubicin. FeRx partnered with Elan Corp. plc, of Dublin, Ireland, in October 2000 for MTC-DOX in the U.S. and Europe, but the two companies dissolved their joint venture two years later as part of Elan's restructuring efforts. FeRx never repartnered the product.

MagneTarg involves magnetic particles that have the ability to carry pharmaceutical agents. It delivers drugs to desired sites using an externally positioned magnet. The drug is injected into the body and delivered directly to the tumor. The microparticles remain after the magnet is removed.