The United States Food and Drug Administration (FDA) has approved Darzalex® (daratumumab) for the treatment of multiple myeloma among patients who have received at least one prior therapy. The new FDA indication also requires that daratumumab be used in combination with either lenalidomide and dexamethasone, or in combination with bortezomib and dexamethasone.
Daratumumab is already approved for use as a single agent for multiple myeloma among patients who have received at least 3 prior treatments including a proteasome inhibitor (PI) and an immunomodulatory agent, or among those who have stopped responding to both of these types of treatment.
Multiple myeloma is considered a type of blood cancer, and is characterized by an excess proliferation of certain cells in the immune system called plasma cells. In 2016, it is estimated that approximately 30,330 new patients will be diagnosed with multiple myeloma in the United States, and approximately 12,650 people are expected to die from the disease. Once patients with multiple myeloma experience cancer progression following standard therapies, prognosis remains poor.
Daratumumab is an agent that targets a specific molecule called CD38, which is found in large quantities on the surface of multiple myeloma cells. Daratumumab binds to CD38, and through a series of responses by the body, death occurs to the cells to which daratumumab binds.
The clinical trials prompting the latest daratumumab approval are referred to as the CASTOR and POLLUX studies. The CASTOR trial included nearly 500 patients with multiple myeloma that had returned or stopped responding to prior therapy. One group of patients in the trial was treated with daratumumab plus bortezomib and dexamethasone; a second group of patients was treated with bortezomib and dexamethasone (a standard treatment regimen). Outcomes between the two treatment groups were directly compared.
- Anti-cancer responses were achieved in 79% of patients treated with daratumumab/bortezomib/dexamethasone, compared with 60% for patients treated with bortezomib/dexamethasone only.
- The median time to progression of cancer has not yet been reached among the group of patients treated with daratumumab/bortezomib/dexamethasone, compared with 7.2 months for those treated with bortezomib/dexamethasone only.
The POLLUX study included nearly 570 patients whose cancer had progressed or stopped responding to standard therapy. One group of patients in this trial was treated with daratumumab plus lenalidomide and dexamethasone; a second group of patients was treated with lenalidomide and dexamethasone (a standard treatment regimen). Outcomes between the two treatment groups were directly compared.
- Anti-cancer responses were achieved in 91% of patients treated with daratumumab/lenalidomide/dexamethasone, compared with 75% for patients treated with lenalidomide/dexamethasone only.
- Patients treated with daratumumab/lenalidomide/dexamethasone had a 63% reduced rate of cancer progression at the time of the last update of the trial, compared to those treated with lenalidomide/dexamethasone only.
Patients with multiple myeloma that has stopped responding to standard therapies now have additional treatment options available that continue to improve the outcomes of this disease.
Reference: Genmab. Genmab News. Genmab Announces U.S. FDA Approval of DARZALEX® (daratumumab) for Relapsed Multiple Myeloma and Updates Financial Guidance. Available at: http://ir.genmab.com/releasedetail.cfm?ReleaseID=1000611.