Revenue is soaring for Carlsbad drugmaker Ionis Pharmaceuticals Inc. thanks to an uptick in one drug’s sales during the second quarter.

Although the company has yet to file an earnings statement for the second quarter (ended June 30), it did release an update on its guidance for 2017 due to “improved financial results” during the first half of the year.

During the first half of the year, the company reported an operating income of $12.3 million, compared to an operating loss of $103.6 million during the same period last year.

The improvements to the bottom were largely due to increased sales of Spinraza, a drug for spinal muscular atrophy that was approved for sale by regulators last December. The drug brought in $47 million in sales for Ionis in the first quarter, and $203 million in the second quarter, according to Ionis. That’s not including the $57 million of milestone payments paid to Ionis from the local company’s partner on the drug, Biogen.

Sales are booming in part because of adoption overseas, said B. Lynne Parshall, chief operating officer at Ionis.

"In June, Spinraza was approved in the European Union with sales already in Germany and the Nordics, and additional country rollouts planned through 2018,” Parshall said in a statement. “In addition, Spinraza has been approved in Japan and Canada, and is under review in several other key countries with additional filings planned in 2017.”

Based on the company’s strong financial performance during the first half of the year, Ionis announced it was revising its guidance for 2017. The company is projecting to end the year with operating income in the mid-$50 million range and a year-end cash balance of more than $950 million.