There are about 400 FDA approved drugs with black box warnings. Almost every day I administer drugs with black box warnings in my anesthesiology practice. Two commonly used black box warning drugs I use are succinylcholine (a muscle relaxant) and droperidol (used as an antiemetic). As clinicians, we weigh the risks and benefits of every medication we use and we are aware of the potential adverse events. We also know how to recognize those events and respond appropriately. Often, drugs with black box warnings are still the best choice.
Well said Dr. White. I would only add that many drugs have been associated with SJS/TEN with a higher incidence of this serious immune mediated drug reaction than has been observed with Incivek and they do not have black box warnings e.g. Bactrim. And as you note, these drugs continue to be used by clinicians, for appropriate conditions, observing for rashes, and discontinuing the offending drugs when they occur, and providing treatment to avoid the most serious complications. I would agree that the boxed warning involving Incivek may in fact slow sales further next year, but it's the next generation of IFN free treatment is really what people with Hep C are waiting for, and the net impact on Vertex of declining sales of Incivek next year will be offset by the increasing sales of Kalydeco in Europe, and the results of clinical trials in CF, RA (and other autoimmune diseases), influenza and IFN free hep C treatments which will show the real growth potential of this company.