Medivation in San Francisco said several companies courted it before it chose Japan's second-largest drug company, Astellas Pharma Inc., as a partner in the development of its prostate cancer drug.
"We were talking to these global pharmaceutical companies, and with all of them it's very much a David and Goliath sort of situation," Medivation's Machado said.
"What you frequently get from the Western companies is pretty much an insistence that they get to call all the final shots. With Japanese companies -- very, very consistently -- they are looking for a consensus-based arrangement, and that's very attractive to us."
Another winning point may be that Japanese firms are not known for company takeovers aimed at selling assets and cutting overhead costs.
Yasuchika Hasegawa, Takeda's president, told a recent Tokyo business leadership forum his view of takeovers.
"Unfortunately, I don't have a management team that has the expertise and capability to pull something like that off," he said.
Hasegawa said Japanese companies were still struggling to achieve diversity in their own offices to become truly global and were generally not ready to do the type of takeovers commonly found in Western countries, at least not yet.
An industry securities analyst said although California did have much to offer, it was important to remember that the location ultimately wasn't what mattered.
"Biotechs in California are like the high-tech companies in Silicon Valley" in the past, said Fumiyoshi Sakai, senior analyst at Credit Suisse Securities in Tokyo.
"If I might say, I'd think Japanese companies would travel to the South Pole if there was a company with a desirable compound they wanted to cut a deal with."
Nagano is a special correspondent.