What happened

Shares of Tandem Diabetes Care (NASDAQ:TNDM) gained over 14% last month, according to data from S&P Global Market Intelligence. The insulin pump provider reported second-quarter and first-half 2019 operating results that beat expectations from Wall Street and outpaced management's own guidance. 

To put the operating results into perspective, consider that Tandem Diabetes Care said it had shipped about 100,000 insulin pumps in the four years ended March 2019. It then shipped 21,258 insulin pumps in the second quarter alone -- cementing its claim to being one of the best growth stocks on the market in recent years.

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So what

Tandem Diabetes Care has made waves with its t:slim X2 insulin pump, which modernizes and simplifies the user experience compared to the status quo of bulky and difficult-to-use devices. The product offers continuous glucose monitoring, over-the-air software updates, and a slick smartphone dashboard. 

Focusing on user experience has been great for business. Tandem Diabetes Care reported first-half 2019 revenue of $159 million, marking 159% growth from the year-ago period. The company also shrank its operating loss from $29.5 million to just $12.8 million in that span. It should start accumulating operating profits in the second half of the year.

Now what

Management significantly increased full-year 2019 guidance and now expects revenue of at least $350 million for the year, compared to previous expectations for at least $300 million. Investors should know that the year-over-year growth comparisons will soon begin to slow because the t:slim X2 launched in Q3 2018, but that's hardly much to complain about. Tandem Diabetes Care remains on a promising long-term trajectory.

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