Shares of drug developer MannKind Inc. rose in after-hours trading Monday despite reporting a larger-than-expected second quarter loss due to higher research and development costs.

Valencia-based MannKind said its losses grew 11 percent to $79.8 million, or 79 cents per share, in the second quarter ended June 30. The company lost $72 million (-98 cents) a year ago. Analysts surveyed by Thomson Financial expected a loss of 74 cents per share.

Operating expenses rose more than $5 million to $80.9 million in the quarter, as research and development expenses increased10 percent to $67.6 million.

The expenses derive from late stage clinical trials the company is completing for its Technosphere inhaled insulin system, the first product it plans to bring to market. The company said it plans to submit the system for U.S. Food and Drug Administration approval by the end of the year.

Shares slid to a low of $2.53 this spring after competing drug companies either pulled or stopped developing competing inhaled insulin products due to safety concerns. Shares have since recovered slightly but are still well below the nearly $20 of two years ago.

MannKind shares closed up 4 cents to $3.79 in regular trading on the Nasdaq, and rose an additional 10 percent to $4.15 in after-hours trading.