Did Albert Einstein do any experiments to prove e equals mc2?

Einstein was a theoretician who proposed a framework for analysis of our Universe which did at least two things: (1) led to the formula E = mc^2 and (2) completely changed our fundamental understanding of our Universe. Prior to publishing his ideas, he did no experiments to test if any of the predictions of his work were, indeed, correct.

His framework COULD have been wrong; he would not have been the first person to make such a mistake. However, in the last 107 years, no reproducible experiment has ever been performed that would contradict the predictions of his framework. And, every time someone uses a GPS device, it works ONLY by assuming Einstein was correct.