AstraZeneca has begun construction on a $100 million R&D expansion at the company’s Waltham, MA facility. The expansion will accommodate up to 100 additional researchers who will join the more than 450 existing employees focused on discovering treatments for infectious diseases and cancer. “This is the right investment at the right time, as hospital-acquired infectious diseases — also known as superbugs — are on the rise and cancer remains the third leading killer ...