The parents of a Michigan teenager who killed herself while on the antidepressant Paxil cannot sue the drug's manufacturer because a state law grants immunity to the maker of any drug approved by the Food and Drug Administration.

U.S. District Judge Paul L. Maloney of the Western District of Michigan said FDA approval of Paxil use by adults was enough to shield manufacturer SmithKline Beecham Corp., even though the agency never approved the drug's use by teens.

He therefore dismissed Nadine White and David B. McCullough's lawsuit against SKB over their 16-year-old daughter Moriah's 2001 suicide after taking Paxil for three months.

Michigan is the only state with a law providing drugmakers immunity from state tort suits if the FDA has certified their products as safe and effective. The only exceptions to the statute are for fraud on the FDA or bribery of an agency official.

In this case, White and McCullough filed a negligence and strict-liability suit against SKB in a Pennsylvania federal court because the company is located in that state.

The drugmaker won a change of venue to the Western District of Michigan because the plaintiffs are residents of that state. It then filed a motion to dismiss.

In their opposition to the motion the plaintiffs argued that their suit is a failure-to-warn case because SKB never warned doctors not to prescribe Paxil to teens or children and, in fact, conducted a secret campaign to promote such "off-label" use.

Moreover, since the company never applied to the FDA for marketing approval to prescribe the drug to teens and children, it cannot argue that it has immunity under the Michigan statute, they said.

Judge Maloney rejected that argument, saying the Michigan Legislature provided immunity to drug manufacturers for FDA-approved products and that it is uncontested that Paxil was approved by the agency for use in adults.

"The statute does not limit the protection to situations when the drug is used for approved purposes," he said. "Should the Legislature wish to limit the protection available to "off-label" uses of the drug, it may do so."