At $ 2 million, the most expensive drug ever deals with a deadly genetic disease

US regulators have approved the most expensive drug ever, for a rare disorder that destroys baby's muscle control and kills almost everyone with the most common type of illness in a few years.

The treatment costs $ 2.125 million. The costs borne by patients vary depending on the insurance coverage.

The drug, sold by Swiss drug maker Novartis, is a gene therapy that treats an inherited condition called spinal muscular atrophy. The treatment targets a defective gene that so weakens a child's muscles that it becomes unable to move and ultimately unable to swallow or breathe. It strikes approximately 400 babies born in the United States each year.

The Food and Drug Administration on Friday approved treatment, called Zolgensma, for all children under 2 years of age confirmed by genetic testing for one of three types of the disease. The therapy is a single infusion that lasts about an hour.

Novartis said it would let insurers make their payments over a five-year period, up to $ 425,000 a year, and give partial discounts if the treatment did not work.

The only approved anti-disease drug in the United States is a drug called Spinraza. Instead of a single treatment, it should be administered every four months. Biogen, the manufacturer of Spinraza, applies a list price of $ 750,000 the first year, then $ 350,000 a year thereafter.

The Institute of Clinical and Economic Review, an independent non-profit group that evaluates the value of expensive new drugs, has calculated that the price of new gene therapy is justifiable at a cost of 1.2 to 2.1 million dollars, because it "radically transforms the lives of families affected by this devastating disease."

Dr. Steven D. Pearson, president of ICER, has called the price of treatment "a positive result for patients and the entire health system".

The defective gene that causes muscle atrophy of the spine prevents the body from making enough protein that allows the nerves that control the movement to function normally. The nerves die without the protein.

In the most common type, which is also the most serious, at least 90% of patients die before the age of 2 and all those who are still alive need a ventilator to breathe. Children of less severe types become disabled more slowly and can live up to two decades.

Zolgensma works by providing a healthy copy of the defective gene, which allows the nerve cells to start producing the necessary protein. This stops the deterioration of nerve cells and allows the baby to develop more normally.

In patient tests, infants with the most severe form of the disease who contracted Zolgensma within 6 months of birth had limited muscle problems. Those who received the treatment the sooner did the best.

Babies who received Zolgensma after six months stopped losing muscle control, but the drug can not reverse the damage already done.

Evelyn Villarreal was one of the first children treated, at eight weeks old. His family, from Centerville, Virginia, had lost his first child to spinal muscular atrophy at 15 months. Two years later, at the time of Evelyn's birth, a test revealed that she also had this condition. The family enrolled her in the gene therapy study at Nationwide Children's Hospital in Columbus, Ohio.

Evelyn is now 4 ½ years old and has no muscle problems other than mild standing problems, said her mother, Elena Villarreal. She has been feeding for a long time, she draws and speaks well, and will begin kindergarten in the fall.

"She is very active and often goes to the playground," said Elena Villarreal. "She walks and even jumps."

According to Dr. Jerry Mendell, a neurologist at Nationwide Children's, it's too early to know how long the benefit of treatment will last, but doctors hope more and more to last a lifetime. Mendell led one of the first studies on patients and is Evelyn's doctor.

"It's starting to look like this," he said, as some treated children aged 4 or 5 still have no symptoms.

Because early diagnosis is essential, Novartis is working with states to obtain genetic testing for newborns at birth. He expects most states to meet this requirement next year.

The FDA has indicated that side effects include potential vomiting and liver damage. Patients should therefore be monitored during the first months after treatment.

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