Drugmakers look to push the boundaries of old age

Google's (GOOG.O) ambition to defy the limits of ageing has fired up interest in the field, drawing in drug companies who are already quietly pioneering research, despite the regulatory and clinical hurdles that remain.

In September life-science company Calico, which was set up by Google last year to investigate the ageing process, joined with U.S. drugmaker AbbVie (ABBV.N) in committing an initial $250 million apiece to developing cures for age-related diseases.