First-in-human study of mivebresib (ABBV-075), an oral pan-inhibitor of bromodomain and extra terminal proteins, in patients with relapsed/ refractory solid tumors

Sarina A. Piha-Paul, Jasgit C. Sachdev, Minal Barve, Patricia LoRusso, Russell Szmulewitz, Sapna Pradyuman Patel, Primo N. Lara, Xiaotian Chen, Beibei Hu, Kevin J. Freise, Dimple Modi, Anjla Sood, Jessica E. Hutti, Johannes Wolff, Bert H. O'Neil

Research output: Contribution to journalArticlepeer-review

52 Scopus citations


Purpose: Bromodomain and extraterminal (BET) proteins play important roles in transcriptional regulation relevant to cancer pathogenesis, and therapeutic targeting/inhibition of BET causes apoptosis of cancer cells in vitro. In this first-inhuman study of the pan-BET inhibitor mivebresib (ABBV-075), the safety profile, MTD, and recommended phase II dose (RP2D) were determined in patients with advanced solid tumors. Patients and Methods: A 3 þ 3 dose escalation for different mivebresib dosing schedules [daily, Monday/ Wednesday/Friday (M-W-F), 4 days on/3 off (4/7)] was followed by dose expansion in patients with prostate cancer. Endpoints were safety, tolerability, pharmacokinetics, and preliminary antitumor activity. Results: Seventy-two patients with solid tumors (14% uveal melanoma; 11% colorectal; 11% breast; 8% pancreatic; 7% head/neck; 49% others) were treated with mivebresib during dose escalation, and 12 additional patients with prostate cancer in expansion cohort. Most common treatment-emergent adverse events (TEAE) related to mivebresib were dysgeusia (49%), thrombocytopenia (48%), fatigue (26%), and nausea (25%). Most common grade 3/4 TEAEs related to mivebresib were thrombocytopenia (35%) and anemia (6%). Dose-limiting toxicities included thrombocytopenia (2 mg daily; 4.5 mg M-W-F), gastrointestinal bleed (2 mg daily), hypertension (2–3 mg 4/7), fatigue, decreased appetite, and aspartate aminotransferase elevation (4 mg M-W-F). Of 61 evaluable patients from dose escalation, 26 (43%) had stable disease and 35 (57%) had progressive disease. Median progression-free survival was 1.8 months (95% confidence interval, 1.8–1.9). Conclusions: On the basis of safety and tolerability, mivebresib RP2D is 1.5 mg for the daily schedule, 2.5 mg for 4/7, and 3 mg for M-W-F. Mivebresib has a tolerable safety profile, and stable disease was observed in some patients with malignant solid tumors.

Original languageEnglish (US)
Pages (from-to)6309-6319
Number of pages11
JournalClinical Cancer Research
Issue number21
StatePublished - Nov 1 2019

ASJC Scopus subject areas

  • Oncology
  • Cancer Research


Dive into the research topics of 'First-in-human study of mivebresib (ABBV-075), an oral pan-inhibitor of bromodomain and extra terminal proteins, in patients with relapsed/ refractory solid tumors'. Together they form a unique fingerprint.

Cite this