Roche and Qiagen are developing a blood test that will help identify patients who would benefit from one of two AstraZeneca lung drugs. Reuters reports that success would mean a simple blood test could replace the need to extract tissue samples, a process which usually requires a needle biopsy or surgery. Reuters says the blood test would use technology that “can detect small fragments of circulating tumor DNA in the plasma.”

The expectation is that the test will be used to identify patients for AstraZeneca’s approved lung cancer drug Iressa and for the still-experimental AZD9291, which could be Iressa’s successor.