MannKind Corp. on Monday reported a higher quarterly loss than analysts projected, attributing the decline to higher operating and R&D costs as the company prepares for another round of clinical trials. The Valencia biotech reported a net loss of $51.8 million (-23 cents a share), compared with a loss of $36.4 million (-30 cents) in the same period a year earlier. Analysts projected earnings of 18 cents a share for the quarter ended Dec. 31, according to Thomson/First Call. Total operating expenses rose more than 8 percent to $33.5 million. The company attributed the increase to clinical-trial related costs for its Afrezza insulin inhaler. The company, which has no products on the market, reported no revenue. MannKind had $61.8 million in cash and short-term investments. It raised $86 million in a dilutive public offering of common stock and warrants in October. For the full year, the company reported a loss of $147 million, compared with a loss $141 million in 2011. MannKind, which has been struggling to get its Afrezza insulin inhaler approved by the Food and Drug Administration, plans to resubmit the device for approval in the third quarter, following the completion of two additional clinical trials. Shares closed down 5 cents, or less than 2 percent, at $2.56 on the Nasdaq.