The U.S. launch of Abbott Laboratories' (ABT) - Get Report continuous glucose monitoring system FreeStyle Libre is off to a strong start.

The debut of Libre, which was approved for sale by the U.S. Food and Drug Administration last September, "has gone exceptionally well," said Abbott chairman and CEO Miles White on an earnings call on Wednesday, April 18. FreeStyle Libre, which was initially launched in Europe in 2014, already has a little over 50,000 users in the U.S., according to White.

Globally, the device has more than 650,000 users, White said. The product is adding 50,000 users a month and Abbott estimates that there will be more than a million users globally by year's end.

Abbott, an Action Alerts PLUS holding, announced in January that Libre had obtained approval to be reimbursed by Medicare patients with diabetes who meet the eligibility criteria.

The product led a double-digit revenue rise in the diabetes care segment of Abbott's medical device unit in the first quarter. Diabetes care generated revenue of $421 million, up 44.2% year-over-year on a reported basis, including a favorable 11.3% effect from foreign exchange.

Overall, Abbott Park, Ill.-based Abbott on Wednesday reported first-quarter results that exceeded analysts' top- and bottom-line estimates, but shares were down 2.8% to $58.11 on Wednesday morning. Some investors may have expected Abbott to increase its full-year profit guidance, Evercore ISI analyst Vijay Kumar told Reuters.

The company's adjusted earnings came in at 59 cents a share, just edging the 58 cent Wall Street consensus and up 22.9% from the same period last year. Sales for the quarter also topped estimates, rising 16.7% to $7.4 billion, versus expectations of $7.3 billion.

Abbott said it expects to see adjusted earnings of between 70 cents and 72 cents a share for the current quarter. The company said its projected full-year adjusted diluted EPS remains in the $2.80 to $2.90 range. Analysts estimated, on average, adjusted EPS of $2.86 for 2018, according to FactSet.

Among the topics that came up during the earnings call was the potential impact of tariffs.

White said the estimated impact of potential tariffs on Abbott's earnings per share will be a penny, calling it a manageable outcome. Abbott makes some products in China and brings products made there to the U.S. Those are diagnostics products that became part of Abbott through its acquisition of Alere Inc.

Abbott stock is up 1.8% year-to-date and up 33.8% over the last months.

-- Martin Baccardax contributed to this article

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