Washington, DC (CNN Business) Uber is blowing through billions of dollars, but CEO Dara Khosrowshahi is undeterred.

In an interview with CNN correspondent Christiane Amanpour that will air Wednesday, Khosrowshahi defended Uber's business model, which involves the company investing heavily in promotions to entice customers to its on-demand ride and meal-delivery offerings.

"The model is absolutely sustainable," Khosrowshahi said. "The business, for example, is still growing 30-plus percent on a global basis. And anytime you have a business that has the kind of market size of trillions of dollars in terms of transportation and food and global commerce, it makes sense for a company to invest."

Uber UBER lost $5.2 billion in the three months ending in June, its largest quarterly loss ever . Stock-based compensation related to its initial public offering accounted for $3.9 billion, but the remaining $1.3 billion in losses were still 50% higher than the year before.

Uber's stock has fallen roughly 30% since going public in May. It raised $8.1 billion in one of the largest public offerings ever.