Pelabresib (CPI-0610)

CPI-0610 inhibits MM(multiple myeloma) cell growth in the presence of cytokines and when co-cultured with bone marrow stromal cells. CPI-0610 induces apoptosis and G1 cell cycle arrest associated with MYC downregulation. However, protein levels of BCL2, NF-κB and MCL1 remain unchanged in MM cells upon BET inhibition. CPI-0610 suppresses Ikaros and IRF4 expression at the levels of both transcription and protein in MM cells^[2].

In a mouse xenograft model using MV-4-11 acute myeloid leukemia cells, MYC mRNA levels of CPI-0610-treated mice were substantially reduced at 4 h compared to the vehicle control and recovered toward the control level at the later time points, which corresponded with decreasing free concentrations of compound in plasma. BET bromodomain inhibition by CPI-01610 resulted in substantial suppression of tumor growth over the time period examined (41%, 80%, and 74% tumor growth inhibition, respectively), without any significant body weight loss in the animals. On the basis of an acceptable toxicity profile in rat and dog, A common set of toxicities was observed in both species: lymphoid depletion; hypocellularity of the bone marrow with associated anemia and thrombocytopenia; GI mucosal atrophy, erosion, and ulceration; degeneration of the testicular seminiferous epithelium; and mild to moderate hyperglycemia. These toxicities is reversible^[1].

• Cell lines

  MV-4-11 cells

• Concentrations

  --

• Incubation Time

  4 h

• Method

  MV-4-11 cells were plated at 10,000 cells/well in 96-well plates containing compounds in 100 μL RPMI medium supplemented with 10% FBS. Cells were incubated with compound for 4 hours at 37◦C and 5% CO2 prior to analysis of MYC transcript levels. Inhibition was calculated relative to DMSO treated MYC levels.

• Animal Models

  mouse xenograft model using MV-4-11 acute myeloid leukemia cells

• Dosages

  15 mg/kg twice daily

• Administration

  s.c.