Interim results from a Phase 3 clinical trial indicate that pomalidomide plus low-dose dexamethasone extends the progression-free and overall survival of relapsed and refractory multiple myeloma patients, as compared to high-dose dexamethasone alone.

The results are from a European clinical trial known as MM-003.  The trial includes multiple myeloma patients who relapsed or did not respond to at least two prior therapies.  Half of the patients were treated with poma­lido­mide (Pomalyst) plus low-dose dexamethasone (Decadron), and the other half were treated with high-dose dexamethasone alone.

A data safety monitoring board, which analyzed the results and determined the survival benefits, recommended that study participants initially assigned to take high-dose dexamethasone and who had not yet progressed should be switched to pomalidomide plus low-dose dexamethasone.

The review board also found that safety results from the trial were consistent with those from previous studies of pomalidomide for the treatment of pre-treated multiple myeloma.

Celgene (NASDAQ: CELG), the company developing pomalidomide, announced the results from the MM-003 trial this morning and said that additional data from the study will be presented at a medical meeting.

Pomalidomide belongs to the same class of drugs as thalidomide (Thalomid) and Revlimid (lenalido­mide) – two drugs that Celgene already markets as myeloma treatments in the United States and internationally. Celgene is developing pomalidomide as a potential new treatment for multiple myeloma and for myelo­fibrosis, a disorder of the bone marrow in which the marrow is replaced by scar (fibrous) tissue.

The U.S. Food and Drug Administration (FDA) and the European Medicines Agency (EMA) are both currently reviewing applications for the approval of pomalidomide in combination with dexamethasone for the treatment of relapsed and refractory multiple myeloma patients who have received at least two prior therapies.

The FDA is required to make its decision about pomalidomide’s new drug application by February 10, 2013.

The MM-003 trial is being conducted as a formal part of Celgene's application to market pomalidomide in Europe.  The news therefore bodes well for the drug’s eventual approval by European regulators sometime next year.

The news also bodes well for pomalidomide's eventual approval in the U.S.  It is unclear, however, what the impact of the news will be on the potential timing of U.S. approval.

If Celgene formally submits the new MM-003 clinical trial results to the FDA for it to consider as part of pomalidomide’s new drug application, that would extend by six months the deadline for the U.S. regulator to decide on the application.

This does not mean that the agency would actually take all of the extra six months to reach a decision on the application.  But it could delay the decision past the current February 2013 deadline.

The FDA announced last month that it had scheduled a meeting in November with one of its advisory committees to review pomalidomide's new drug application.  The meeting was canceled earlier this month, however, without a clear indication as to why it was canceled (see related Beacon news).   A new date for the meeting has not yet been set, nor is it clear that such a meeting will take place.  The FDA is permitted to decide on a new drug application without consulting with one of its advisory committees.

If the FDA makes a positive decision regarding pomalidomide’s new drug application, Celgene will be allowed to start marketing the drug in the U.S. as a new treatment for relapsed and refractory myeloma.

Until the FDA reaches a decision regarding pomalidomide’s application, the drug is available through Celgene’s expanded access program, called PEXIUS, for relapsed and refractory myeloma patients in the U.S. who do not have any other treatment options.

For more information about the pomalidomide trial results announced today, see the Celgene press release.