Last year, Humira (adalimumab) was the top-selling drug in the U.S., racking up nearly $20 billion in international sales. Now, Boehringer Ingelheim’s Cyltezo (adalimumab-adbm) has become the first interchangeable Humira biosimilar. First winning FDA approval in August 2017, Cyltezo is a tumor necrosis factor blocker indicated for everything from arthritis to Crohn’s, ulcerative colitis and…