Vioxx’s maker, Merck & Co., faced lawsuits from 47,000 people and for years said it would fight them individually, but now has agreed to pay $4.85 billion to settle.

— May 1999: U.S. Food and Drug Administration approves Vioxx for treatment of arthritis and acute pain.

— June 2000: Merck, based in Whitehouse Station, N.J., gives FDA results of a study known as VIGOR, in which patients taking Vioxx had five times the heart attacks of those taking an older pain reliever, naproxen, that Merck contended protected the heart.

— September 2001: FDA sends Merck a warning letter saying a promotional campaign “minimizes the potentially serious cardiovascular findings” and “misrepresents the safety profile of Vioxx.”

— April 2002: FDA changes Vioxx package insert to reflect VIGOR heart attack findings.

— September 30, 2004: Merck voluntarily withdraws Vioxx from the market after halting its own study that showed Vioxx doubles risk of heart attack or stroke.

— February 2005: FDA panel concludes Vioxx and other similar drugs all pose heart risks, but can remain on sale.

— August 19, 2005: In the first Vioxx trial, a Texas jury awards $253.4 million to the widow of Robert Ernst, who died in May 2001. Texas punitive damage caps later cut that to about $26 million.

— February 17, 2006: In a retrial after a hung jury, federal jurors in New Orleans clear Merck in the May 2001 death of Richard “Dicky” Irvin. In May 2007, a federal judge orders a third trial, saying a Merck witness misrepresented qualifications.

— April 11, 2006: A state jury awards $13.9 million to John McDarby, 77, who had a heart attack in April 2004. But it absolves Merck in the case of Thomas Cona, 60, stricken in June 2003.

— April 21, 2006: A jury in Rio Grande City, Texas, awards $32 million to the family of Leonel Garza, 71, who had heart disease for 23 years and died in 2001 after less than a month on Vioxx. Later reduced to about $7.75 million under state damage caps.

— July 13, 2006: A jury in Atlantic City, N.J., rules Merck was not responsible for a heart attack suffered by Elaine Doherty, 68.

— August 8, 2006: A Los Angeles jury clears Merck in the 2001 heart attack suffered by Stewart Grossberg, 71.

— August 17, 2006: A federal jury in New Orleans orders Merck to pay $51 million to Gerald Barnett, who had a heart attack September 6, 2002. A federal judge later rules that amount is “grossly excessive” and in June 2007, Mr. Barnett agrees to an award of $1.6 million rather than go to trial again.

— September 26, 2006: A federal jury in New Orleans clears Merck in the case of Robert Garry Smith, 56, of Kentucky, who suffered a heart attack in 2003.

— September 30, 2006: A surge of lawsuits hits courthouses ahead of the second anniversary of Merck withdrawing Vioxx from the market, the deadline for patients in 22 states with a two-year limit on initiating personal injury lawsuits.

— November 15, 2006: A federal jury in New Orleans clears Merck in the July 2003 heart attack suffered by Charles Laron “Ron” Mason, 64, of Utah.

—November 22, 2006: A federal judge in New Orleans rules that federal lawsuits over Vioxx cannot be combined into one national class action.

— December 13, 2006: A federal jury in New Orleans clears Merck in the 2003 heart attack of Anthony Dedrick, 50, of Tennessee.

— December 15, 2006: Jurors in Birmingham, Ala., clear Merck in the 2001 heart attack suffered by Gary Albright, 57.

—March 2, 2007: A jury in Atlantic City, N.J., rules against the widow of Brian Hermans, 44, of Wisconsin, but rules Merck violated New Jersey’s consumer fraud law, letting the family recoup Vioxx copayments and about $2 million in legal fees.

— March 12, 2007: In a retrial granted because of new evidence, an Atlantic City jury awards Frederick “Mike” Humeston, 61, of Idaho $47.5 million in damages.

— March 27, 2007: A jury in Edwardsville, Ill., sides with Merck and rejects claims that Vioxx caused the fatal 2003 heart attack of Patty Schwaller, 52.

— April 12, 2007: A federal judge dismisses a securities class action lawsuit alleging Merck had defrauded investors by concealing information about Vioxx’s safety risks, because the statute of limitations expired.

— April 27, 2007: FDA rejects Merck’s request to market a successor to Vioxx, Arcoxia, two weeks after advisers voted 20-1 against approval.

— September 6, 2007: New Jersey’s Supreme Court rejects a potential class-action lawsuit brought on behalf of health insurance plans seeking to recoup what they paid for Vioxx, setting the stage for individual lawsuits.

— November 9, 2007: Merck says it will pay $4.85 billion to end thousands of Vioxx lawsuits. It’s one of the largest drug settlements ever.