Onyx/S*Bio: One of the biggest deals between a U.S. company and an Asian biotech has come undone. Onyx Pharmaceuticals walked away from its option agreement with Singapore’s S*Bio, covering two janus kinase inhibitors, SB1518 and SB1578 in North America & Europe. Announced in January 2009 and broadened in 2010, Onyx paid $25 M upfront (this includes equity) plus an additional $20 M when it was expanded; potential milestone payments were up to $550 M in total. SB1518 was in Phase II for entry indication, myelofibrosis- (in April, S*Bio announced the 10th patient being dosed in N. America). Lymphoma was a secondary indication. Onyx’s decision came as the company announced redoubled focus on its potential blockbuster proteasome inhibitor carfilzomib, obtained when it acquired Proteolix in 2009. S*Bio said it will seek a new partner urgently, with a goal of beginning a pivotal Phase III trial on SB1518 later this year.

What's your guess- difficult niche positioning? too competitive ( hence too risky) in the JAK space, which has all the biggies Incyte/ Novartis, YM BioSciences/ sanofi, AZ, Lilly, BMS), high costs?

acknowledgements: invivoblog, S*Bio's press release