Merck was fined $321,636,000 Thursday by U.S. District Court Judge Patti B. Saris in Boston after pleading guilty in December to one misdemeanor count related to its promotion and marketing of the painkiller Vioxx, the Justice Department said Thursday afternoon.

In November 2011, Merck settled civil charges under which it agreed to pay $628,364,000 over additional allegations regarding off-label marketing of Vioxx and false statements about the drug's cardiovascular safety.

The $950 million total in fines closes the case, the Justice Department said.