Back in the day, I worked in a lab studying the effects of an alternative NF-kB pathway on osteoclast differentiation (osteoclasts eat up bone) and growth. One of the papers demonstrated that certain anti-cancer drugs (used in breast cancer, not the ones described in this paper however) drove up regulation of that pathway, leading to increased bone resorption (thus causing osteoporosis). Now, clinically, this was probably managed fairly well with bisphosphonates, however it raises the question of whether or not these types of combo regimens are going to lead to similar types of side effects.
Regardless of that, if the results in this article are trialed, I suspect this will go exceedingly well for therapies that immunotherapies have been hard pressed to treat (alluded to in the conclusion, of course). Kudos to the group, well done.