Astellas snaps up cancer antibody play Ganymed for up to $1.4B

Astellas Pharma expects to beef up its oncology franchise with the purchase of German biotech Ganymed Pharmaceuticals for what could be a total of $1.4 billion. The Japanese pharma is already partnered with Pfizer ($PFE) on prostate cancer treatment Xtandi (enzalutamide), which had $2.2 billion in global net sales over the past year.

Astellas was partnered with Medivation on Xtandi under a 2009 deal, which transferred to Pfizer ($PFE), of course, after the recently closed $14 billion acquisition. With this Ganymed purchase, Astellas gains lead candidate IMAB362, which recently had positive Phase IIb data in gastroesophageal cancer that stole the show at ASCO.

"Oncology is one of our focus therapeutic areas and key drivers for our growth,” said Astellas President and CEO Yoshihiko Hatanaka in a statement. "The acquisition of Ganymed will enable Astellas to further expand our oncology presence by adding a late-stage antibody asset with the potential to establish a new pillar following Xtandi. We aim to deliver a potential new therapeutic option to cancer patients who currently have limited treatment options available to them."

Under the deal, Astellas is paying €422 million ($461 million) upfront; it will pay up to an additional €860 million ($940 million) in milestones based on the progress of IMAB362. In addition to the GI data, that candidate is in preclinical testing for other solid tumors including pancreatic cancer. The deal is expected to close in the next several weeks; Ganymed will become a subsidiary of Astellas.

Ganymed’s majority shareholder is ATS Beteiligungsverwaltung, which is a family office for well-known German biotech investors the Strüngmann brothers. Future Capital and MIG Fonds are also investors in the biotech. Ganymed reportedly has raised $113 million in venture capital, with the most recent infusion being a $60 million Series E round in 2013.

"We are pleased to hand over the Ganymed portfolio with its important novel treatment approaches for unmet needs in solid tumors to a strong and dedicated player in healthcare,” said Ganymed board member and general manager of the Strüngmann family fund Helmut Jeggle.

A first-in-class candidate, IMAB362 is selective and specific for the tight junction protein Claudin-18.2 (CLDN18.2). This target is responsible for regulating paracellular permeability and sealing the space between epithelial and endothelial cellular sheets. CLDN18.2 is overexpressed in up to 80% of GI cancers and 60% of pancreatic and other solid cancers. It is expected to have little to no effect on healthy cells, given its selectivity.

In the Phase IIb data, gastroesophageal cancer patients treated with IMAB362 extended the median time to disease progression versus chemotherapy alone to 7.9 months from 4.8 months; the median overall survival rate was stretched to 13.2 months from 8.4 months. And among the patients with the highest levels of Claudin18.2, the median overall survival was 16.7 months with IMAB362 and 9 months on chemotherapy alone.