Two major court victories for Merck on Thursday pushed the litigation over the painkiller Vioxx closer to conclusion and highlighted the increasing difficulty that plaintiffs’ lawyers were having in winning lawsuits against big drug companies.

A state appeals court in Texas overturned a $26 million jury verdict against the company in a lawsuit brought by Carol Ernst, whose husband, Robert, died in 2001 after taking Vioxx. In reversing the verdict, the appeals court found that plaintiffs had not proved that Vioxx caused Mr. Ernst’s death.

Separately, an appeals court in New Jersey sharply reduced a verdict in another Vioxx case. The court ruled that the jury should not have been allowed to award punitive damages against Merck or to find that Merck had committed consumer fraud. Only compensatory damages of $4.5 million were permitted, the court said.

The rulings on Thursday leave lawyers for plaintiffs with just three victories, all with relatively small awards, in the nearly 20 Vioxx cases that have reached juries. Mark Lanier, a plaintiffs’ lawyer who was involved in both cases decided Thursday, criticized the decisions and promised appeals. But plaintiffs face an uphill battle.

In Carol Ernst’s eyes, two years ago she won a measure of justice.

On Aug. 19, 2005, a Texas jury awarded Mrs. Ernst $253.5 million after concluding that Merck & Company and its painkiller Vioxx had caused the death of her husband, Robert, in 2001. At a news conference after the verdict, Mrs. Ernst said she was pleased that jurors had punished Merck for hiding Vioxx’s heart risks. “This has been a long road,” she said. “I just know that it was a road that I had to run and I had to finish.”

But her comfort was premature. Merck, the third-largest American drug maker, appealed the verdict — which Texas laws on punitive damages automatically reduced to $26.1 million. Until higher courts rule on the appeal, Merck is not obligated to pay. So Mrs. Ernst, 62, has yet to receive any money.

In fact, none of the 45,000 people who have sued Merck, contending that they or their loved ones suffered heart attacks or strokes after taking Vioxx, have received payments from the company. The lawsuits continue, for now in a state of legal limbo, with little prospect of resolution.

In combating the litigation, Merck has made an aggressive, and so far successful, bet that forcing plaintiffs to trial will reduce the number of Vioxx lawsuits and, ultimately, its liability.

Merck was found not liable in the seventh lawsuit over Vioxx, the arthritis painkiller that it pulled from the market because of heart attack risk, the company announced Thursday.

The jury of five men and two women found Vioxx was not a substantial factor in the heart attack of a 68-year-old New Jersey woman, a court clerk said. The trial was held at New Jersey Superior Court in Atlantic City.

The jury decided that although Merck failed to warn the plaintiff, Elaine Doherty, about the heart risks of taking Vioxx, it did adequately warn her doctor of such risks, the clerk said.

The panel also found that Merck did not commit consumer fraud or misrepresent Vioxx in marketing the drug to physicians or to the plaintiff, the clerk said.

Jim Fitzpatrick, an outside counsel for Merck, said in a press conference that the verdict “reiterates our strategy to defend these cases on an individual basis.”

Michael Galpern, attorney for Doherty, told CNNMoney.com that he had not decided whether to appeal, but his firm is representing more than 500 plaintiffs in upcoming Vioxx cases.

“This was actually a major victory for plaintiffs across the country as this was the first time that the jury was asked if Merck failed to warn the patients about the dangers of Vioxx and the answer was yes by a unanimous verdict,” said Galpern. “Unfortunately they found that Vioxx did not cause Mrs. Doherty’s heart attacks, and we are disappointed with that one.”