RE:RE:RE:RE:RE:RE:AstraZeneca's ADC disappoints - on severe adverse eventsAnti-body drug conjugates (ADCs) are small molecules. Under the IRA, Medicare can begin negotiations on these as early as nine years after they are approved by the US Food and Drug Administration approval, compared with 13 years for biologics. Pfizer is now likely weighing these new facts into any of their proposed acquisitions.