Amgen Inc. could greatly expand its market for cholesterol drug Repatha if an upcoming study is successful, according to an announcement Friday from the Thousand Oaks biotech company. The company’s stock went up close to 2 percent. Repatha is now sold to those who’ve had a cardiac event. But if the study shows the drug can lower the risk of death, heart attack, stroke or revascularization in patients who have not yet had a cardiac event, if could increase the market for Repatha by 4.5 million patients, according to an article in Investor’s Business Daily. The study, called Vesalius-CV, will involve at least 13,000 patients worldwide and last for a minimum of four years. Testing is due to begin in the second quarter. The Medicines Co., a rival biotech business in New Jersey, is conducting a similar test for cholesterol drug Inclisiran. Amgen aims to have its study completed seven months ahead of the Medicines Co., which already has an eight-month lead, the Investor’s article said. Shares of Amgen (AMGN) on Friday closed up $3.48 to $191.24 on the Nasdaq, an increase of 1.9 percent.