Abbvie Inc. and Google-backed California Life Sciences LLC, better known as Calico, have agreed to pour up to $750 million each into a new discovery and development collaboration devoted to advancing neurodegeneration and cancer therapies through phase IIa and beyond. The celebrity life sciences start-up, led by former Genentech executives, including Art Levinson, will establish a research and development facility in the San Francisco Bay area.

The companies will each provide up to $250 million to fund the collaboration at first. Calico will carry out R&D work for the first five years of the collaboration, with Abbvie providing support and an equal share of program costs under terms of the agreement. Each partner may also chip in up to $500 million more, but what might trigger those investments is unclear. Both Abbvie and Calico declined interview requests.

Levinson, Calico's founder and CEO, called the Abbvie relationship "a pivotal event" for the young company, suggesting that it would "turbocharge" Calico's efforts to understand the science of aging and advance its clinical work.

Franz Humer, chairman of Basel, Switzerland-based Roche AG, applauded Levinson's decision to lead Calico a year ago, expressing hope that Roche and Calico could work together in the future. For now though, that seems unlikely. Levinson resigned Thursday from the board of Genentech parent Roche AG, effective immediately, to avoid any conflict of interest given his role at Calico. Levinson remains chairman of Apple Inc., which is widely expected to launch its own health-related products Sept. 9.

Abbvie and Calico are clearly plotting a long-term course. Calico said it would advance partnered projects through phase IIa for up to 10 years, while Abbvie is maintaining an option to manage late-stage development and commercial activities in the collaboration. Both parties will share costs and profits equally.

Abbvie CEO Richard Gonzalez said the collaboration demonstrates his company's commitment to "exploring new areas of medicine and innovative approaches to drug discovery."

His company spent about $2.9 billion on R&D in 2013. Gonzalez said Abbvie is also pleased to be working with the likes of Levinson and Hal Barron, another former Genentech star who is now Calico's president of R&D, and their team, which includes among others, David Botstein, one of the world's leading geneticists, and Cynthia Kenyon, a top authority on the molecular biology and genetics of aging.

Calico said it expects to begin filling critical positions immediately and plans to establish a substantial team of scientists and research staff in the San Francisco Bay area.

While Calico could be one of Google's biggest forays into the life sciences space, it's certainly not the first. In July, the company licensed a smart-lens technology to Alcon, a unit of Novartis AG. With its non-invasive sensors, microchips and other miniaturized electronics embedded within contact lenses, the technology could potentially provide diabetics with a continuous measure of their glucose levels or provide adaptable vision correction for people with presbyopia. Google Ventures also has invested in the consumer genetics company 23anme Inc.

First announcing Calico in September 2013, Google CEO Larry Page said it was "clearly a longer-term bet," but that "we can make good progress within reasonable timescales with the right goals and the right people."