Recently, Onyx Pharmaceuticals Inc. (ONXX) received a major setback as the US Food and Drug Administration (FDA) did not grant accelerated approval designation to the company’s new drug application (NDA) for carfilzomib. Onyx Pharma is seeking to get carfilzomib approved as a treatment for patients with relapsed and refractory multiple myeloma.
The regulatory body has granted a standard review designation to the candidate’s NDA and set a target date of July 27, 2012.
The FDA in its letter to Onyx Pharma said that the application and the study supporting the application are insufficient to review the NDA on a priority basis. The regulatory body has also said that since the NDA is based on a single-arm study, it is concerned whether the benefit and risk of the candidate are appropriately balanced.
It was also mentioned in the letter that the FDA’s advisory committee prefers late-stage study results for granting accelerated approval designation to a candidate’s NDA, whereas, carfilzomib’s NDA was based on mid-stage trial (003-A1) results.
The phase II trial had demonstrated that patients, dosed with the said candidate, experienced an overall response rate of 24.1%, while the clinical benefit rate was higher at 34.2%. The duration of response was 8.3 months, while the median overall survival was 15.5 months. The patients, who enrolled in the study, had already received a median of five prior lines of therapy and their disease was refractory to their last therapeutic regimen.
Additionally, the FDA had granted orphan drug designation to carfilzomib for the treatment of multiple myeloma in 2008.
We note that Onyx Pharma is conducting a phase III study (FOCUS) to support the European filing of carfilzomib as a treatment for relapsed and refractory myeloma. Top-line data from the study is expected in the first half of 2012.
Our View
We currently have a Neutral recommendation on Onyx Pharma. The stock carries a Zacks #3 Rank (Hold rating) in the short-run. The news of the FDA not granting carfilzomib’s NDA accelerated approval designation comes as a disappointment for Onyx Pharma, which is heavily banking on the approval of the candidate as currently it just has one marketed product, Nexavar (cancer), in its portfolio.
We believe that any further delay in the approval of carfilzomib as a treatment for refractory multiple myeloma would weigh heavily on the stock.
