DRDO doesn't declare any specific cutoff for direct recruitment. It calls candidates for interview depending on the number of vacancies. Candidates are called for interviews in a ratio of 1:5.
For e.g., if there are 10 openings for mechanical engineers, DRDO will call 50 mechanical engineers for interview. The GATE cutoff to get called for an interview should be around 890 (normalized score). As you can see, it is very difficult to get into DRDO.