Maryland has fired the contractor that built its expensive online health insurance marketplace, which has so many structural defects that officials say the state might have to abandon all or parts of the system. The Maryland Health Benefit Exchange voted late Sunday to terminate its $193?million contract with Noridian Healthcare Solutions. Columbia-based Optum/QSSI, which the state hired in December to help repair the flawed exchange, will become the prime contractor, and Noridian will assist with the transition. "We worked very hard with [Noridian] to find a path forward," said Isabel FitzGerald, the Cabinet secretary in charge of information technology. "And the decision now is that we are just not making the progress that we had hoped."