More than 425,000 Californians have signed up on the state’s health insurance exchange — with nearly 100,000 rushing to enroll in the last four days before the 2016 open enrollment period ended Jan. 31, officials said Thursday.

Parker Conrad, CEO and co-founder of once high-flying Zenefits, has resigned amid a scandal involving allegations that employees sold insurance without holding proper licenses to do so.

Embattled drug entrepreneur Martin Shkreli — who vigorously defended his decision to hike the price of a life-saving drug from $13.50 to $750 — suddenly went silent Thursday at a Congressional committee, smirking and grinning instead of answering questions.

Stung by losses under the federal health law, major insurers are seeking to sharply limit how policies are sold to individuals in ways that consumer advocates say seem to discriminate against the sickest and could hold down future enrollment.

President Barack Obama will propose tailoring the controversial "Cadillac tax" on expensive private health insurance plans to reflect regional differences when he releases his 2017 budget plan next week, a senior White House adviser said in an article released on Wednesday.

A new hospital model is coming to the Las Vegas Valley. Dignity Health, which runs three St. Rose Dominican campuses in Henderson and southwest Las Vegas, plans four smaller neighborhood hospitals across the Las Vegas Valley in the next two years.