Physicians Ugur Sahin and Oezlem Tuereci, who bonded over their love of medical research, are the married couple behind the Covid-19 vaccine that could change the world. Mr Sahin came from humble roots to build two billion-dollar companies but still rides to work on his mountain bike. Now the 'modest' 55-year-old physician turned chief executive of a German biotech firm and his wife Oezlem Tuereci, 53, a fellow board member ...