Genmab A/S entered its second DuoBody deal with a large pharmaceutical firm inside two months. The Copenhagen, Denmark-based antibody developer entered a broad collaboration with the Johnson & Johnson subsidiary Janssen Biotech Inc. to develop bispecific antibodies against Janssen-supplied targets.

It is banking $3.5 million up front and could receive up to $175 million more in milestone and license payments for each successfully developed product.

The alliance could involve up to 10 separate programs, although a much smaller number will commence initially.

For Genmab, the deal represents additional validation for its bispecific antibody platform, following a deal it entered in early June with Basel, Switzerland-based Novartis AG. The present deal represents a sharp uplift not only in potential size but also in terms.

"The royalties as well as the milestones payable to us have more than doubled," Genmab CEO Jan van de Winkel told BioWorld International.

Novartis entered a two-product deal, with $175 million in total milestones on offer. The up-front element of the deal, though small, also increased, from $2 million to $3.5 million. (See BioWorld International, June 6, 2012.)

As the technology matures and gains further validation, it will become more expensive to access. "The future deals will step up from here," van de Winkel said.

The company is taking a leaf out of the deal-making handbook of Bothell, Wash.-based Seattle Genetics Inc., whose deal sizes have grown successively larger as its antibody-drug conjugate technology has gathered momentum.

The targets and indications involved have not been disclosed, although cancer represents the principal focus of many bispecific antibody development efforts.

"Overall cancer is the key area," van de Winkel said. "Other companies have shown proof of concept in inflammatory disease and central nervous system disease."

Bispecific antibody technologies have been gaining increasing visibility ever since Amgen Inc. shelled out $1.16 billion to acquire Micromet Inc., whose bispecific T-cell engager (BiTE) antibodies direct a T-cell response at tumor cells by simultaneously binding the T-cell receptor CD3 and a tumor antigen of interest. (See BioWorld Today, Jan. 27, 2012.)

Other platforms in the space come from the Genentech Inc. unit of Basel-based Roche Holding AG; Abbott, of Abbott Park, Ill.; Geneva-based NovImmune SA; and Rockville, Md.-based Macrogenics Inc.

The only bispecific antibody to reach the market so far is Removab (catumaxomab), developed by Trion Pharma GmbH and Fresenius Biotech GmbH. The molecule, which gained European approval in 2009 for treating malignant ascites (abdominal fluid) in cancer patients, targets the T-cell antigen CD3 and epithelial cell adhesion molecule (EpCAM; CD326).

Others involved in the area include Paris-based Sanofi Group, which recently began clinical trials of SAR156597, a bispecific antibody targeting interleukin-4 and interleukin-13, in idiopathic pulmonary fibrosis.