Genmab A/S said it is moving full steam ahead with its late-stage HuMax-CD4 compound in cutaneous T-cell lymphoma after regaining full rights to the drug from partner Merck Serono SA.

The companies signed the potential $215 million deal in August 2005, for exclusive worldwide rights to HuMax-CD4, a monoclonal antibody that has been granted fast-track and orphan drug status by the FDA. The compound is in a pivotal Phase III study in CTCL, but Genmab CEO Lisa Drakeman assured investors during a conference call that Merck's decision to return HuMax was based on "strategic reasons," and that no one has seen any data yet from the pivotal trial.

"We are delighted that we will regain all rights," she said, adding that Genmab is "celebrating" the news. That's largely due to the fact that the company is in a much different position than it was when it licensed HuMax-CD4 rights two years ago to Serono in exchange for $70 million up front and up to $145 in milestones, plus development costs. (See BioWorld Today, Aug. 19, 2005.)

At that time, Genmab still was going it alone with HuMax-CD20 (ofatumumab), and needed resources to advance that program and others in its pipeline. But late last year, the company partnered HuMax-CD20 with London-based GlaxoSmithKline plc in a potential $2.1 billion deal that included a $100 million licensing fee up front and an equity investment valued at about $360 million. That agreement also comes with a co-promotion option for Genmab to build a small U.S. sales force. That same sales force potentially could market HuMax-CD4 as well. (See BioWorld Today, Dec. 20, 2006.)

"We've said we really want to build commercial operations in some way," Drakeman said, adding that the return of HuMax-CD4 rights could be a "pivotal step" in that direction. The worldwide market for CTCL and noncutaneous T-cell lymphoma is estimated at about $500 million. No decisions have been made yet on whether to seek other partnerships or distribution agreements for the product, but those plans will be discussed "over the coming months," she added.

For now, the Copenhagen, Denmark-based firm is focused on proceeding quickly with the ongoing Phase III CTCL study, which is expected to involve a total of about 90 patients with CTCL, a disease characterized by an accumulation of malignant T cells in the skin that can develop into rashes and tumors. HuMax-CD4 is designed to work by targeting CD4, a receptor that is exclusive to T cells. The trial's primary endpoint is the rate of complete and partial responses during treatment and an eight-week follow-up period.

While Genmab had hoped to release pivotal results by the end of the year, Drakeman said patient accrual is proceeding more slowly than expected. "So, realistically, we will not have data until next year."

HuMax-CD4 also is in Phase II testing in noncutaneous T-cell lymphoma. Development costs for those ongoing studies are expected to be handled by Merck through the end of 2007, per the companies' partnership agreement. And Genmab is not required to reimburse Merck for any funding to date, Drakeman said.

That leaves the company resources for other pipeline programs, and Genmab is moving forward on a Unibody compound targeting the CD4 receptor to block and neutralize HIV infection. Laboratory studies to date have shown that the compound effectively blocked HIV-1 replication and reduced depletion of CD4-positive T cells in an immunodeficient mouse model.

Genmab expects no change to its 2007 guidance. The company, which reported a net loss of DKK76.8 million (US$13.7 million) for the first quarter, anticipates a net loss for the full year to fall within the range of DKK260 million to DKK310 million. As of March 31, Genmab's cash and marketable securities totaled DKK4.2 billion.

Shares of Genmab, listed on the Copenhagen Stock Exchange under "GEN," closed at DKK353.50 Friday, up DKK4.50.