"Because a number of us had built or led small companies, we had the attitude of being a different kind of partner," Daniel said in an interview. "It was not just to be sort of the Big Pharma judge and jury, but to really be collaboratively engaged with the small company."
Nick Leschly, chief executive of Celgene partner Bluebird Bio, put it another way: "Celgene gets it."
"Their opening line in negotiations is: 'What's important to you?'" Leschly said in an interview at the ASH conference. Bluebird is presenting data at the meeting Monday, though on a different program than the one partnered with Celgene. "They're very keen and focused on making sure incentives are aligned."
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In many cases, that's involved Celgene taking an equity stake in its partners—a strategy that's begun to take on value of its own as many have gone public and their market values have grown.
Celgene is the largest shareholder of Agios, with a 15 percent stake. It also owns large portions of partners Acceleron, Epizyme and OncoMed. It's not an investment strategy, Daniel said, though in cases like Agios, it hasn't hurt; Agios' stock is up more than 340 percent year to date.
Owning stock gives Celgene "a voice at the table," Daniel said, "basically to be an owner, to be participating in the board activities and following the progress of the company at the most senior level."
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Some partnerships have also come with exclusive options for Celgene to acquire the smaller companies, such as its April 2014 deal with Forma Therapeutics and its February 2014 deal with Abide Therapeutics.
As the list of Celgene's collaborations has grown, though, the challenge may become proving that each has the potential to make a significant impact, RBC's Yee said.
"When it first started coming out, some of these partnerships were being viewed as extremely prestigious," Yee said. "Now some pundits might say they seem to be throwing money everywhere, so each incremental one loses a little bit of prestige."
Yee noted, though, that recent collaborations like an April licensing deal for a Crohn's disease drug have excited investors. That medicine is in later stages of testing than many others on which Celgene's formed partnerships.
As the strategy provides access to new technologies, it's also yielded an "outside-in cultural transformation" for the $90 billion company, Daniel said.
"I think we're valuably impacted by small company can-do attitudes—hungry entrepreneurs determined to prove that they've got something of great, great value and importance," he said. "Not only are we strong by virtue of the network, but we're also stronger inside because we're connected to it."