Enough people have signed on to Merck & Co.’s pending $4.85 billion Vioxx settlement to keep the deal moving forward, the drug maker announced.

Enough people have signed on to Merck & Co.’s pending $4.85 billion Vioxx settlement to keep the deal moving forward, the drug maker announced.

The company said more than 44,000 of the 47,000 claimants who registered injuries eligible for compensation have submitted some or all of the documentation required to seek a share of the settlement. Vioxx was pulled from the market in 2004 when the widely used painkiller was linked to heart attacks and strokes. After a few years of litigation, a comprehensive settlement was proposed in November.

Friday was the deadline for accepting the offer, and at least 85% of eligible claimants had to enroll by submitting forms and medical authorizations in order to validate the deal. More than 93% have joined the pact, though it isn’t yet clear how many of those meet all the criteria. People who submitted partially completed enrollment packages have until March 31 to turn in the rest of their materials.

Claimants next are required to provide medical records that third-party administrators will use to assess what payment they might qualify for. Under the settlement plan, a claim must be based on an incidence of heart attack, ischemic stroke or sudden cardiac death. Plaintiffs must provide documentation showing that Vioxx was taken for at least 30 days and show that the injury occurred within 14 days of using the drug. Payouts will be adjusted according to other cardiovascular risk factors.

Plaintiffs lawyers estimate that, depending on age and risk factors, settlement payments will range from $50,000 to $1.5 million, with an average exceeding $200,000. Merck, of Whitehouse Station, N.J., set aside $1.9 billion for litigation costs — not including any payouts — and spent $1.2 billion. But plaintiffs had trouble persuading juries that Vioxx, and not other risk factors, had caused injuries. Of the 16 cases that went to trial, Merck prevailed in 11. Some plaintiffs won big, though: At the first Vioxx trial, a jury in August 2005 awarded a Texas widow $253.4 million — later reduced to $27.2 million, including interest.