Perifosine added to the combination of Bortezomib and Dexamethasone. Perifosine is is supplied as a film-coated tablet containing 50 mg of active ingredient. Perifosine will be administered orally on an outpatient basis throughout the study. Daily administration will be one 50 mg tablet.

The first dose of perifosine should be taken on the same day that bortezomib and dexamethasone are administered (Cycle 1 Day 1).

Perifosine placebo added to the combination of Bortezomib and Dexamethasone. The placebo for perifosine is provided in 256 mg white to off-white, round, biconvex film-coated tablets to permit a blinded trial with perifosine 50 mg film coated tablets. Placebo will be administered orally on an outpatient basis throughout the study. Daily administration will be one perifosine placebo tablet. The first dose of placebo should be taken on the same day that bortezomib and dexamethasone are administered (Cycle 1 Day 1).

Perifosine will be dosed as one 50 mg pill every day of each cycle.

Progression-free survival will be defined as the time between randomization and the date of progression that occurred during the Core Phase.

OS is defined as time from randomization to death from any cause during the Core Phase of the study.

The ORR for each treatment arm will be estimated as the proportion of responders, defined as a patient whose best overall response is PR or better during the treatment period, using criteria prospectively established.