iHDAC IC50 Clinical trial identifier HDAC specificity Chemical structure Biologic event Cell type Model Reference Citarinostat (ACY-241) 2.6 nM (HDAC 6) and 46 nM (HDAC 3) No trials registered HDACs 1, 2, 3, and 6 Inhibition of plasma cell myeloma proliferation and survival; cell cycle disruption MM1, H929, U266 Human [74 ] ACY-738 1.7 nM for HDAC 6 selectively No trials registered HDACs 1, 2, 3, and 6 Pre-B cell growth inhibition in lupus disease MRL/lpr bone marrow cells Mouse [68 ] BML-281 0.002 nM (HDAC 6), 271 nM (HDAC 1), 252 nM (HDAC 2), 0.42 nM (HDAC 3), 6851 nM (HDAC 8), 90.7 nM (HDAC 10) No trials registered HDAC 6 Blocks B cell infiltration in acute colitis CD19+ B lymphocyte Mouse [71 ] Dacinostat (LAQ824) 32 nM No trials registered Pan iHDAC Decreases viability in B-ALL, multiple myeloma, and B lymphoma cells SEMK RS4;11 SEMK2 697 Namalwa Daudi Ramos MM1S-N OPM2 PMI8226 Human [75 ] Givinostat (ITF2357) BCR-ABL signaling pathway No trials registered Classes I, II Cell proliferation inhibition and apoptosis induction in chronic myelogenous leukemia, BCR-ABL1-positive and childhood B acute lymphoblastic leukemia K-562, SUP-B15 Human [76 ] LMK-235 11.9 nM (HDAC 4), 4.2 nM (HDAC 5) No trials registered HDACs 4, 5 Induces apoptosis and BCLA1 overexpression in diffuse large B cell lymphoma OCI-Ly10, OCI-Ly3 Human [77 ] Entinostat (MS-275) 0.51 μ M (HDAC 1), 1.7 μ M (HDAC 3) in cell-free assays (1) NCT03925428 (2) NCT00098891 (3) NCT00020579 HDACs 1, 3, 4, 6, 8, and 10 Proliferation inhibition and apoptosis induction; enhancement of DNA damage response in plasma cell myeloma U266, MM1.R, RPMI8226 Human [78 ] Dose-/time-dependent cell death, gene expression disruption, and CD20 upregulation in rituximab-sensitive Burkitt lymphoma (BL) and RL (germinal centre B cell) Raji-4RH, RL-4RH, and U2932-4RH and lymphoma cells derived from patients with untreated or relapsed/refractory B cell lymphoma Human [79 ] Decreases cell viability in B-ALL, B-lymphoma, and multiple myeloma cell lines SEMK2, RS4;11, SEMK2, 697, Namalwa, Daudi, Ramos, MM1S-LN, OPM2, RPMI8226 Human [75 ] Panobinostat (LBH589) 5 nM in a cell-freeassay (1) NCT01282476 (2) NCT01238692 (3) NCT01523834 (4) NCT00978432 (5) NCT00918333 (6) NCT01261247 (7) NCT00962507 (8) NCT02961816 European Medicines Agency approved for use and FDA accelerated approval for use in multiple myeloma (2015) Classes I, II, and IV Reduced cell number and viability; delayed division progression; decreases the number of CD138+ antibody-secreting cells B cell B220+ , CD19+ , IgM+ , IgD+ Mouse [69 ] Reduces autoantibody-producing plasma cells MRL/lpr mouse autoimmunity Mouse [69 ] Primary germinal centre response inhibition C57BL/6 Mouse [69 ] Dose-dependent proliferation and tumor growth inhibition; apoptosis induction CLBL-1 cells Dog [80 ] RGFP966 0.08 μ M in cell-free assay No trials registered HDAC 3 Induces apoptosis, decreases Bcl-2 and Bcl-xL expression. Myc-mediated miR expression Epstein-Barr virus-related Burkitt lymphoma Human [81 ] Eμ -myc EM330 Mouse Ricolinostat (ACY-1215) 5 nM in a cell-free assay. Low activity against HDAC 4/5/7/9/11, sirtuin 1, and sirtuin 2 (1) NCT02091063 (2) NCT02787369 HDAC 6 CD20 expression Peripheral mononuclear cell from CLL patients Raji cells Human [82 ] Romidepsin (FK228, depsipeptide) 36 nM (HDAC 1), 47 nM (HDAC 2) in cell-free assays (1) NCT01846390 (2) NCT02281279 (3) NCT00079443 (4) NCT00963274 (5) NCT01897012 (6) NCT02181218 (7) NCT00383565 (8) NCT03432741 (9) NCT01947140 (10) NCT01998035 FDA approved for cutaneous T cell lymphoma (2009) HDACs 1, 2 Reduced cell number and viability B cell B220+ , CD19+ , IgM+ , IgD+ Mouse [69 ] Tacedinaline (CI994) 0.9 μ M (HDAC 1), 0.9 μ M (HDAC 2), 1.2 μ M (HDAC 3), >20 μ M (HDAC 8) No trials registered Class I Dose-dependent proliferation inhibition CLBL-1 cells Dog [80 ] Trichostatin A (TSA) 1.8 nM in cell-free assays No trials registered Pan iHDAC CD20 expression Raji cells Human [82 ] Dose-dependent proliferation inhibition CLBL-1 cells Dog [80 ] Tubacin 4 nM in a cell-free assay No trials registered HDAC 6 CD20 expression EBV-positive Burkitt lymphoma EBV-negative Burkitt lymphoma EBV-negative DLBCL cell lines EBV-transformed lymphoblastoid cell lines Peripheral mononuclear cell from CLL patients Raji cells Human [82 ] Dose-dependent proliferation inhibition CLBL-1 cells Dog [80 ] Tubastatin A 15 nM in a cell-free assay No trials registered HDAC 6 CD20 expression Raji cells Human [82 ] Vorinostat (SAHA, MK0683) 10 nM in a cell-free assay (1) NCT00097929 (2) NCT00764517 (3) NCT02589145 (4) NCT03150329 (5) NCT00667615 (6) NCT00703664 (7) NCT01193842 (8) NCT00972478 (9) NCT00875056 (10) NCT01567709 (11) NCT01120834 (12) NCT01276717 (13) NCT00992446 (14) NCT00499811 (15) NCT01116154 (16) NCT01789255 (17) NCT01500538 (18) NCT00601718 (19) NCT00275080 (20) NCT03259503 (21) NCT00253630 (22) NCT03842696 (23) NCT00791011 (24) NCT00994500 (25) NCT00217412 (26) NCT00837174 (27) NCT00720876 (28) NCT00005634 (29) NCT00918723 FDA approved for cutaneous T lymphoma (2006) Classes I, II, and IV CD20 expression Raji cells Human [82 ] Reduced cell number and viability; delayed division progression; decreases the number of CD138+ antibody-secreting cells B cell B220+ , CD19+ , IgM+ , IgD+ Mouse [69 ] Dose-dependent proliferation inhibition CLBL-1 cells Dog [80 ] Cell viability decrease, apoptosis induction Raji, Raji-4RH, RL-4RH, RL, and patient primary tumors Human [83 ] Enhances apoptosis mediated by kinase inhibitors that affect BCR signaling and gene expression disruption in mantle cell lymphoma Jeko-1, Mino Human [84 ] Induces cell death in rituximab-sensitive Burkitt lymphoma (BL) and RL (germinal centre B cell) Lymphoma cells derived from patients with untreated or relapsed/refractory B cell lymphoma Human [79 ] Scriptaid 9 μ M (Ishikawa endometrial cancer cell line) and 55 μ M (SK-OV-3 ovarian cancer cell line) No trials registered Pan iHDAC CD20 expression Raji cells Human [82 ] Dose-dependent proliferation inhibition CLBL-1 cells Dog [80 ] Suberohydroxamic acid (SBHA) 0.25 μ M (HDAC 1), 0.3 μ M (HDAC 3) No trials registered HDACs 1 and 3 Dose-dependent proliferation inhibition CLBL-1 cells Dog [80 ] Src tyrosine kinase Gardner-Rasheed feline sarcoma viral (v-FGR) oncogene homolog (FGR) mediates SAHA resistance BL-2, BL-41, BL-70, Blue-1, CA-46, Daudi, DG-75, DND-39, Namalwa, Raji (Burkitt lymphoma), Carnaval, Granta-452, HBL-1, HT, Kis-1, OCI-Ly1, OCI-Ly2, OCI-Ly3, OCI-Ly7, OCI-Ly10, SU-DHL-4, SU-DHL-6, TMD8, U2932, WSU-DLCL2, WSU-FSCCL (diffuse large B cell lymphoma) Human [85 ] Valproic acid Selectively induces proteasomal degradation of HDAC 2 (1) NCT01622439 (2) NCT00109824 (3) NCT02144623 Approved for use in the treatment of epilepsy Pan iHDAC Class-switch DNA recombination (CSR) and plasma cell differentiation C57BL/6J Mouse [86 , 87 ] CD20 expression CLL cell line CLL patients Human [88 ] WT161 8.35 nM (HDAC 1), 15.4 nM (HDAC 2), 0.4 nM (HADC6) No trials registered HDACs 1, 2, and 6 Decreases cell viability in B-ALL, B lymphoma, and multiple myeloma cell lines SEMK2, RS4;11, SEMK2, 697 Human [75 ]