This is a good post from the Pharma Strategy blog explaining what antibody drug conjugates (ADC) are and how they work in treating cancers. ADC's are a hot area in the treatment of cancer and presumably even more so in the future.
Seattle Genetics' brentuximab vedotin (SGN-35), now known as Adcetris, is furthest along toward approval having been granted priority review by August 30th. It is being considered for treatment of Hodgkin's Lymphoma and anaplastic large cell lymphoma.
The next two in line are Roche's T-DM1 for the treatment of Her2+ breast cancers and Seattle Genetics' SGN-75 for the treatment of renal cell carcinomas and non-Hodgkin's lymphoma. Roche has a fairly large pipeline of 6-7 addtional candidates following along. Bone up with this primer and look for more new approvals in this area over the next few years.