Topping the spate of high-dollar collaborations announced Monday, Seattle Genetics Inc. signed Genentech Inc. to a potential $860M partnership to develop SGN-40, a monoclonal antibody in early clinical testing in hematologic cancers.

That news sent shares of Seattle Genetics (NASDAQ:SGEN) shooting up 24 percent, or $1.27, to close at $6.56.

Other deals making headlines in the biotech space included a potential $265 million licensing agreement between Ablynx NV and Boehringer Ingelheim, PTC Therapeutics Inc.'s deal with Pfizer Inc., which could reach more than $141 million, and South San Francisco-based Catalyst Biosciences Inc.'s $100 million research and license agreement with Madison, N.J.-based Wyeth. (See story in this issue.)

For Seattle Genetics, the partnership with Genentech marks its largest deal to date, and involves an exclusive, worldwide license for SGN-40, a product that has generated much interest since early data were presented at scientific meetings last year. The compound is designed to target the CD40 antigen, which is expressed on most B-cell malignancies, as well as on solid tumor types such as bladder, renal and ovarian cancers.

For a drug with that kind of "big market potential, it makes sense to partner it," said Clay Siegall, president and CEO of Bothell, Wash.-based Seattle Genetics. "We went for the number one company in the world that develops antibody drugs for cancer."

Genentech develops and sells the blockbusters Avastin (bevacizumab) for colorectal cancer, and Herceptin (trastuzumab) for breast cancer. Its deal with Seattle Genetics marks the second so far this year. Last week, the South San Francisco-based company agreed to partner on Exelixis Inc.'s MEK inhibitor LX518, in development for cancer. (See BioWorld Today, Jan. 4, 2007.)

Shares of Genentech (NYSE:DNA) closed at $83.80 Monday, up 12 cents.

The companies will work together to develop SGN-40, which is Phase I and Phase II testing in multiple myeloma, chronic lymphocytic leukemia and non-Hodgkin's lymphoma, with Genentech picking up the costs associated with all further development.

Under the licensing terms, Seattle Genetics expects to receive $60 million in up-front cash, and be eligible to receive more than $800 million in milestones, most of which "are focused on regulatory events and product approvals," Siegall told BioWorld Today. Genentech agreed to pay $20 million in committed milestones during the first two years of the collaboration.

Upon commercialization, Seattle Genetics would be looking at a double-digit royalty, "starting from the mid-teens and escalating based on increasing sales figures," Siegall said.

In the U.S., the company holds a co-promotion option, which would be "a great way to begin efforts" to create its own sales force, he added.

In separate news, Seattle Genetics entered a collaboration with Santa Monica, Calif.-based Agensys to co-develop and commercialize cancer drugs using Seattle Genetics' antibody-drug conjugate (ADC) technology.

"That deal's important to us because it's helping to expand our cancer pipeline," Siegall said. "We're getting up to two products we'll be able to co-develop."

The companies agreed to jointly screen and select ADC products to a selected undisclosed target, and will equally share preclinical and clinical development costs as well as any profits. Up to three additional targets could be identified, and Seattle Genetics has the right to exercise a co-development option on one of those at the time an investigational new drug application is filed.

For the remaining two products, the company would be eligible for fees, milestones and royalties.

Work with Agensys likely would focus on solid tumors, "which would be a nice complement to our pipeline, which has more of a hematological focus," Siegall said.

That pipeline includes CD33-targeting antibody SGN-33, in Phase I testing in acute myeloid leukemia and myelodysplastic syndromes, and SGN-70, an anti-CD70 antibody that is in manufacturing for clinical trials. The company also is developing SGN-30, which is in multiple Phase II trials in combination with chemotherapy. Those studies are being conducted in collaboration with the National Cancer Institute.

Ablynx, BI Partner On AD Program

Belgian firm Ablynx could receive nearly $265 million in a worldwide collaboration with Boehringer Ingelheim to discover and develop Alzheimer's disease drugs using Ablynx's Nanobodies platform.

That deal calls for an up-front fee, and development and commercial milestones, and Ablynx also could receive undisclosed royalties on any commercialized product. Ingelheim, Germany-based Boehringer will be responsible for funding work in the collaboration.

Ablynx, of Ghent, Belgium, focuses its discovery efforts on Nanobodies, compounds that are designed to cross the blood-brain barrier with greater ease than conventional antibodies. The company's technology has led to a number of other collaborations, including a November 2005 deal with Wyeth, in which Ablynx could receive up to $212 million for the development and commercialization of Nanobodies directed at the tumor necrosis factor-alpha protein and its receptors. (See BioWorld Today, Nov. 7, 2006.)

PTC, Pfizer Sign $141M-Plus Deal

PTC Therapeutics Inc.'s GEMS technology landed it a partnership with big pharma firm Pfizer Inc. to focus on as many as 10 targets.

In exchange for access to its Gene Expression Modulation by Small-Molecules (GEMS) platform, PTC expects to receive an up-front payment of $10 million, plus a $10 million equity stake and research funding. Beyond that, PTC would earn up to $121 million in milestones per target, and New York-based Pfizer, which would retain exclusive worldwide rights to any product developed, agreed to pay PTC royalties on any product resulting from the collaboration.

The GEMS technology platform is designed to identify small molecules that modulate post-transcriptional control mechanisms, and PTC uses the platform to help build its own internal pipeline. The company's most advanced GEMS-based product, PTC299, an oral, small molecule aimed at inhibiting vascular endothelial growth factor (VEGF) is in Phase I development in healthy volunteers. That product is being developed for cancer.

Elsewhere in its pipeline, the South Plainfield, N.J.-based firm is advancing PTC124, its drug candidate aimed at patients with Duchenne's muscular dystrophy or cystic fibrosis due to a nonsense mutation. Promising Phase II results reported last year showed that PTC124 can restore function of the cystic fibrosis transmembrane conductance regulator protein in airway cells and significantly reduce blood neutrophil counts.

PTC has a preclinical hepatitis C program partnered with Kenilworth, N.J.-based Schering-Plough Corp., and several discovery programs.

The company has a pending initial public offering, which it filed in April, with hopes of raising $86 million to fund ongoing clinical activities.