You can't compare 520 as single agent data vs Elotuzumab plus lenalidomide plus low-dose dexamethasone combination. The patient population are not the same either. 520 patients required to relapse and refractory to both a bortezomib and an IMiD-based regimen while Elotuzumab combination required only one. When patients who had not received lenalidomide before, lenalidomide plus low-dose dexamethasone by themselves can still produce high response rate. Here is Elotuzumab data:
a subset analysis showed that of 22 patients who had not previously received Revlimid® (lenalidomide) treatment, 21 patients (95%) achieved an objective response.
Myeloma is an incredibly crowded space
There is reason for it. With introduction of Revlimid and Velcade, MM patients live longer and longer. Unfortunately for patients but fortunately for biotech/pharma, patients eventually stop responding to existing therapies, and they need to get onto new therapies. Thus MM market have expanded dramatically.
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