McNiven served as backup to Sam Montembeault on Dec. 30 and Jan. 1 in Carolina and Florida, respectively. He has yet to make his NHL debut.
The 24-year-old holds a 30-34-12 record with a 2.89 goals against average and 0.892 save percentage through 80 games with Laval since the 2017-18 season.
McNiven agreed to terms on a one-year, two-way contract extension with the Canadiens in August.
Primeau for his part has made three starts with the Canadiens this season, winning one game, and registering a 3.58 goals against average and 0.904 save percentage.
He was called up most recently on Dec. 27, but went on the NHL's COVID-19 protocol list two days later before returning home to quarantine.
The Farmington Hills, MI native will join the team in Boston later this week and be assigned to the taxi squad.
