In its first clinical-stage partnership since a 2001 deal involving Erbitux, ImClone Systems Inc. agreed to collaborate with UCB Group on an anti-angiogenic candidate about to enter a Phase II trial in non-small-cell lung cancer.

The companies will share equally all development costs for CDP-791, an antibody designed to target the vascular endothelial growth factor receptor-2 (VEGFR-2), also known as the KDR receptor, which regulates the formation of blood vessels in tumors. If clinical development continues successfully, the product could enter Phase III studies around the end of next year.

"It's a very good fit for us," ImClone spokesman David Pitts said of CDP-791. "To our knowledge, it's the most advanced anti-KDR antibody in development."

Financial terms were not provided, though Pitts said the deal does not include the typical up-front fee and milestone payments; instead it features a "fifty-fifty worldwide split of both profits and costs."

New York-based ImClone also would receive incremental single-digit royalties on net sales and retain exclusive commercialization rights to the product in North America. UCB would have rights in Europe, Japan and the rest of the world.

The VEGF pathway has become a popular therapeutic approach in cancer, with the approval of South San Francisco-based Genentech Inc.'s Avastin in metastatic colorectal cancer. Rather than targeting the tumor itself, anti-angiogenic drugs like Avastin essentially starve the tumor by blocking the growth of new blood vessels it relies on for nutrients. UCB's CDP-791, a PEGylated diFab antibody designed to block VEGFR-2, has demonstrated in preclinical studies that it can prevent interaction between VEGF ligands and the receptor to interfere with the development of tumor vasculature.

UCB previously completed a Phase I study of CDP-791 in patients with refractory solid tumors and found the product to be safe and well tolerated. In addition to the upcoming Phase II trial in NSCLC, CDP-791 also could be evaluated in renal, ovarian and colorectal cancers.

While the companies are working jointly on the CDP-791 program, ImClone also plans to advance its own anti-KDR antibody, IMC-1121b, which recently began Phase I testing.

"Basically, this accelerates our ability to enter the anti-angiogenic market by about a year," Pitts told BioWorld Today. "We have a five-year window in the development of both drugs to choose which one is more commercially viable. At the end of that window, we can either drop our program with IMC-1121b or drop the CDP-791 program."

Should ImClone decide not to pursue CDP-791, all rights return to UCB, though ImClone could receive royalties if the product achieves approval.

The collaboration "allows us to diversify the risk of development across two antibodies," said ImClone CEO Dan Lynch during a conference call. It also "allows us to begin filling the gap between Erbitux and our earlier-stage product candidates."

Erbitux, which targets the epidermal growth factor receptor (EGFR), was approved in February 2004 for irinotecan refractory or intolerant metastatic colorectal cancer. The drug is partnered with New York-based Bristol-Myers Squibb Co., and recorded U.S. sales of $97.8 million for the quarter ended June 30.

ImClone and BMS have several late-stage programs evaluating Erbitux in other indications, such as earlier-stage colorectal cancer, NSCLC, head and neck cancer and pancreatic cancer.

The remainder of ImClone's pipeline remains in preclinical or early clinical development. In addition to IMC-1121b, the company has IMC-11F8, a fully human EGFR antibody, in Phase I trials. An investigational new drug application has been filed for IMC-A12, an antibody that targets the insulin-like growth factor receptor, and Pitts said the company expects to submit an IND for a VEGFR-1 inhibitor, IMC-18F1, before the end of the year.

ImClone reported a net income of $26 million, or 30 cents per share for the second quarter, with the majority of its revenue coming from Erbitux sales. As of June 30, the company had cash, cash equivalents and marketable securities totaling $811.8 million.

Development costs associated with the UCB collaboration are expected to increase ImClone's expenses for the year by $3 million to $5 million.

Shares of ImClone (NASDAQ:IMCL) gained 1 cent Tuesday to close at $32.44.