The family of an infant who allegedly suffered a severe reaction to a vaccine may not sue the drugmaker for failing to update the vaccine with a newer, safer version, the US Supreme Court ruled on Tuesday.

In a 6-to-2 decision, the high court said Russell and Robalee Bruesewitz’s lawsuit was preempted under the National Childhood Vaccine Injury Act of 1986. The law grants drug companies immunity from certain lawsuits from injuries or deaths tied to vaccinations.

“We hold that the National Childhood Vaccine Injury Act preempts all design-defect claims against vaccine manufacturers brought by plaintiffs who seek compensation for injury or death caused by vaccine side effects,” wrote Justice Antonin Scalia in the majority decision.

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In a dissent, Justices Sonia Sotomayor and Ruth Bader Ginsburg said that, by preempting all design defect lawsuits by vaccine victims, the high court was imposing “its own bare policy preference over the considered judgment of Congress.”

The decision “leaves a regulatory vacuum in which no one ensures that vaccine manufacturers adequately take account of scientific and technological advancements when designing and distributing their products,” Justice Sotomayor wrote.

Millions of infant vaccines are safely administered each year throughout the United States. But government officials acknowledge that a small percentage of infants experience a severe negative reaction from a vaccine. In some cases the reaction can be fatal.

Faced with open-ended damages from lawsuits filed on behalf of those who suffer severe reactions from vaccines, drug manufacturers considered avoiding the vaccine market altogether.

In passing the National Childhood Vaccine Injury Act, Congress sought to strike a balance that would protect vaccine manufacturers from open-ended liability from private lawsuits while also creating a special fund to compensate those who suffer side effects from vaccines.

Roughly 100 to 200 claims for compensation are submitted each year to a special vaccine court. To date, the compensation fund has paid out $1.8 billion to 2,500 petitioners. The average award is about $750,000.

But compensation is only part of the Vaccine Injury Act’s purpose. Congress also sought to preempt lawsuits seeking open-ended money damages against vaccine manufacturers.

The problem with the law is that Congress did not specifically spell out which lawsuits may move forward in the courts against vaccinemakers and which must be dismissed.

The law says in part that no vaccine manufacturer shall be held liable for a vaccine-related injury or death “if the injury or death resulted from side effects that were unavoidable even though the vaccine was properly prepared and was accompanied by proper directions and warnings.”

Products liability law establishes three grounds for potential liability – if there is a defect in the manufacture, if there were inadequate warnings, or if there is a defective design.

The key issue in the case was why Congress did not mention “defective design” as preempted from potential lawsuits.

The majority justices read the law to sweep broadly, preempting any and all design defect claims provided that the manufacturing process did not create a defect and that warnings and directions were adequate.

“If a manufacturer could be held liable for failure to use a different design, the word ‘unavoidable’ would do not work,” Justice Scalia wrote. “A side effect of a vaccine could always have been avoidable by use of a differently designed vaccine not containing the harmful element.”

He added: “The language of the provision thus suggests that the design of the vaccine is a given, not subject to question in the tort action.” The design itself may not be the subject of a vaccine lawsuit, the court ruled.

In their dissent, Justices Sotomayor and Ginsburg adopted a narrow reading of the statute’s preemption provision. They said Congress intended that vaccinemakers would continue to face the prospect of design-defect lawsuits filed by victims.

In rejecting broad preemption for design defects, the dissenters said, Congress intended for drugmakers to face a continuing “legal duty” to improve the designs of their vaccines in light of advances in science and technology. The high court action on Tuesday eliminated that duty, they said.

“Manufacturers, given the lack of robust competition in the vaccine market, will often have little or no incentive to improve the designs of vaccines that are already generating significant profit margins,” Sotomayor wrote. “Nothing in the text, structure, or legislative history remotely suggests that Congress intended that result.”

The high court decision stems from the April 1992 administration of a vaccine to the Bruesewitzes' then-infant daughter, Hannah. After being injected with the diphtheria-tetanus-pertussis (DTP) vaccine, Hannah suffered a series of seizures that left her developmentally disabled. Lawyers for the family say she will require medical care and supervision throughout her life.

The Bruesewitzes took their claim to the special Vaccine Court, but a month before they filed their petition, Hannah’s seizure disorder was dropped from a listing of injuries covered under the Vaccine Injury Act. The Vaccine Court ruled that the family would receive no compensation.

The family then filed suit in state court alleging that Wyeth Inc., the vaccine manufacturer, was negligent because it could have produced a safer version of the vaccine, but failed to do so. Lawyers for the family argued that the company should have upgraded its vaccine with a less dangerous version.

Wyeth lawyers countered that the federal Vaccine Injury Act preempts such claims made in state court.

The case was moved to federal court, where a judge agreed with Wyeth and ruled that the state lawsuit was preempted by federal law. The Third US Circuit Court of Appeals affirmed. In its ruling on Tuesday, the high court upheld the Third Circuit decision.

Justice Elena Kagan took no part in the case.

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