Those payments will amount to about 40 percent of each plaintiffs' estimated total payout.

The $4.85 billion settlement between Merck and plaintiffs' lawyers was reached last November.

Merck pulled the painkiller from the market in 2004 after its own research showed the once-blockbuster arthritis pill doubled the risk of heart attack and stroke.

Officials say 49,954 eligible claimants have registered for a settlement.