Patients who struggle with high levels of unhealthy cholesterol got some good news on Friday after a new drug was proven to lower the risk of heart attacks and strokes by up to 20 percent.

The drug, called Repatha, is an injection given once or twice a month that works by slashing unhealthy LDL cholesterol by more than half, levels previously considered unthinkable.

"Now I think we have a new mindset for what it means to have a well-controlled LDL cholesterol -- much lower than our current targets," said Dr. Marc Sabantin of Brigham and Woman's Hospital.

Experts say the drug is best for people who are genetically predisposed to extremely high LDL, or those with a history of heart disease.

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