Seattle Genetics had an up and down week last week. The FDA’s Advisory Committee gave a positive recommendation for the company’s Hodgekins lymphoma drug ADCETRIS (brentuximasb) yet the stock went down. The Seattle Genetics Chairman is quoted as saying he is still positive about the drug. We tend to agree with him. Some of the press has been questioning the approvability of the drug because there are only two small studies in support of the application.
There are several things that are very much on the positive side for Seattle Genetics on this. The first is the indication – refractory Hodgekins lymphoma, refractory being the operative word here. The second thing is the data. Yes, the definitive trial presented is a Phase 2 single arm study with only 102 patients but the results were outstanding, clearly much better response rates than literature results for other treatments that have been tried in these patients. The third thing appears to be the dialog that the company has been having with the FDA during the course of the development of this drug. In the Briefing Document for last weeks Advisory Committee, the FDA seems to imply that the company has met all of the agreements they made with the FDA to get to this point. The final point is also a reference the FDA makes in the Briefing Document to the February 2011 meeting of the Advisory Committee in which the criteria for acceptability of a single arm study were discussed. Seattle Genetics seems to have met the criteria discussed and agreed to during that AdComm meeting. So, the only thing standing in the way of approval is company agreement and FDA acceptability of the necessary confirmatory trial.
We think it is likely that Seattle Genetics will continue to listen to and agree with the FDA, particularly with regard to the design of the confirmatory trial. That being the case, FDA seems inclined to approve the drug.