Peter Riedell, MD, on DLBCL: Expert Commentary on the DEB Study

The DEB study was a phase three clinical trial that was recently presented at the ASCO meeting. This study evaluated the combination of R-CHOP with HDAC inhibitor, Tucidinostat. In this trial, it was conducted exclusively in China and it enrolled patients in the frontline setting that had double expressor lymphoma. Double expressor lymphoma is the specific subset of diffuse large B-cell lymphoma that shows increased expression of both MIC and BCL2 without the associated gene rearrangements. In this clinical trial, patients were randomized to either placebo or Tucidinostat in combination with R-CHOP, and they received that for six cycles and then went on to receive either maintenance therapy with Tucidinostat or placebo. The combination of Tucidinostat and R-CHOP in this clinical trial actually yielded increased CR rates compared to R-CHOP therapy alone, and additionally, this translated into an event-free survival benefit as well. Though there's only a short follow-up of approximately 13.9 months median at this point, and therefore we need longer followup to get a better understanding of outcomes. Importantly, this study did not show a difference in overall survival at this point. The combination of Tucidinostat and R-CHOP was relatively well tolerated, though we did see a higher incidence of hematologic toxicity along with infectious complications compared to R-CHOP therapy alone. This is overall my take on this is it's encouraging data, but we do need to have longer term followup. Additionally, questions do still remain regarding if this data is applicable to non-Asian populations, what's the impact of maintenance therapy in this clinical trial that was employed, and then, additionally, how do these results really compare to one of the other standards of care that we use in diffuse large B-cell lymphoma, which is Polatuzumab RCHP.