Development of 2 Bromodomain and Extraterminal Inhibitors With Distinct Pharmacokinetic and Pharmacodynamic Profiles for the Treatment of Advanced Malignancies. Clin Cancer Res 2020 Mar 15;26(6):1247-1257
Date
09/19/2019Pubmed ID
31527168Pubmed Central ID
PMC7528620DOI
10.1158/1078-0432.CCR-18-4071Scopus ID
2-s2.0-85081941841 (requires institutional sign-in at Scopus site) 55 CitationsAbstract
PURPOSE: Bromodomain and extraterminal (BET) proteins are key epigenetic transcriptional regulators, inhibition of which may suppress oncogene expression. We report results from 2 independent first-in-human phase 1/2 dose-escalation and expansion, safety and tolerability studies of BET inhibitors INCB054329 (study INCB 54329-101; NCT02431260) and INCB057643 (study INCB 57643-101; NCT02711137).
PATIENTS AND METHODS: Patients (≥18 years) with advanced malignancies, ≥1 prior therapy, and adequate organ functions received oral INCB054329 (monotherapy) or INCB057643 (monotherapy or in combination with standard-of-care) in 21-day cycles (or 28-day cycles depending on standard-of-care combination). Primary endpoints were safety and tolerability.
RESULTS: Sixty-nine and 134 patients received INCB054329 and INCB057643, respectively. Study INCB 54329-101 has been completed; INCB 57643-101 is currently active, but not recruiting (no patients were receiving treatment as of January 8, 2019). Terminal elimination half-life was shorter for INCB054329 versus INCB057643 (mean [SD], 2.24 [2.03] vs. 11.1 [8.27] hours). INCB054329 demonstrated higher interpatient variability in oral clearance versus INCB057643 (CV%, 142% vs. 45.5%). Most common (>20%) any-grade treatment-related adverse events were similar for both drugs (INCB054329; INCB057643): nausea (35%; 30%), thrombocytopenia (33%; 32%), fatigue (29%; 30%), decreased appetite (26%; 22%). Two confirmed complete responses and 4 confirmed partial responses with INCB057643 were reported as best responses.
CONCLUSIONS: INCB057643 exhibited a more favorable PK profile versus INCB054329; exposure-dependent thrombocytopenia was observed with both drugs which limited the target inhibition that could be safely maintained. Further efforts are required to identify patient populations that can benefit most, and an optimal dosing scheme to maximize therapeutic index.
Author List
Falchook G, Rosen S, LoRusso P, Watts J, Gupta S, Coombs CC, Talpaz M, Kurzrock R, Mita M, Cassaday R, Harb W, Peguero J, Smith DC, Piha-Paul SA, Szmulewitz R, Noel MS, Yeleswaram S, Liu P, Switzky J, Zhou G, Zheng F, Mehta AAuthor
Razelle Kurzrock MD Center Associate Director, Professor in the Medicine department at Medical College of WisconsinMESH terms used to index this publication - Major topics in bold
AdolescentAdult
Aged
Aged, 80 and over
Antineoplastic Agents
Boronic Acids
Dose-Response Relationship, Drug
Female
Humans
Male
Maximum Tolerated Dose
Middle Aged
Nausea
Neoplasms
Organic Chemicals
Patient Safety
Proteins
Pyrimidines
Tissue Distribution
Treatment Outcome
Vomiting
Young Adult
