A new inhibtor (BET - Bromodomain and Extra-Terminal) is being tested in multiple myeloma. The BET proteins interact with acetylated histones. This interaction disrupts genetic expression on cells, potentially creating a genetic disruption that causes myeloma. Prevention of the expression of certain growth-promoting genes may lead to an inhibition of tumor cell growth.

This inhibitor is being tested because myeloma patients can acquire resistance to certain myeloma treatments, so new therapies are needed. BET inhibitors, when first studied, helped kill myeloma cells in the lab and in mice, but they do not kill all myeloma cell types. A "next generation" of BET inhibitors are now being tested and are showing potent activity in leukemia and in myeloma.

The purpose of this study is to test whether a BET inhibitor called RO6870810 is safe at different dose levels and to understand the impact on the myeloma either alone or with daratumumab.

This drug has been tested in a limited number of humans (less than 100), and this is the first time that RO6870810 will be given to patients with multiple myeloma.