DongKoo Bio&Pharma’s largest shareholder, Qurient, has reported promising early anti-cancer effects in Phase 1 clinical trials of their novel drug candidate, Mocaciclib (Q901). Some patients experienced tumor shrinkage or halted disease progression.
Qurient announced on Monday that an abstract detailing Mocaciclib’s Phase 1 trial results has been released ahead of the European Society for Medical Oncology (ESMO 2026) annual conference, scheduled for October 23-27 in Madrid, Spain.
The abstract includes findings from a dose-escalation study involving 65 patients with advanced solid tumors, encompassing safety data, pharmacokinetic and pharmacodynamic analyses, and preliminary efficacy indicators. Comprehensive data will be presented via poster during the conference.
In the trials, Qurient progressively increased Mocaciclib dosages from 18 mg/m² to 168 mg/m². Safety evaluations led to the establishment of a recommended Phase 2 dosing regimen: three weeks on, one week off, with a recommended dose (RP2D) of 126 mg/m².
The study participants were late-stage cancer patients who had previously undergone up to 17 different cancer treatments. Qurient reported that the drug demonstrated a manageable tolerability profile throughout the dosing period.
Of the 53 patients evaluable for efficacy, two achieved partial response (PR) with significant tumor shrinkage, while 16 showed stable disease (SD). Notably, some prostate and ovarian cancer patients exhibited substantial decreases in tumor markers, with instances of disease stability lasting over 40 weeks.
Mocaciclib is a novel drug candidate designed to inhibit cyclin-dependent kinase 7 (CDK7), a protein crucial for cancer cell proliferation and survival. By targeting CDK7, which plays a key role in gene transcription and cell cycle regulation, the drug aims to block the gene expression necessary for cancer cell growth.
CDK7 inhibitors have garnered particular interest due to their potential to impair cancer cells’ DNA damage repair capabilities. This mechanism makes them promising candidates for combination therapies with other anti-cancer drugs, including antibody-drug conjugates (ADCs).
Pharmacokinetic and pharmacodynamic analyses revealed that Mocaciclib’s exposure in the body increased proportionally with the administered dose. Changes in POLR2A gene expression, a biomarker for CDK7 inhibition, were observed even at the lowest dose levels.
Earlier this month, Qurient published research in the prestigious journal Science Advances, elucidating how Mocaciclib enhances the efficacy of TOP1 inhibitor-based ADCs by suppressing pathways involved in cancer cell gene expression and DNA repair.
The company is currently conducting Phase 2 clinical trials to evaluate Mocaciclib in combination with hormone therapies for hormone receptor-positive breast cancer and with ADCs for triple-negative breast cancer.
Nam Ki-yeon, Chief Executive Officer (CEO) of Qurient, stated that the Phase 1 trials successfully validated Mocaciclib’s safety profile and mechanism of action. It’s now entering an exciting phase where it can further explore its efficacy through combination trials and dual payload ADCs, potentially broadening its therapeutic applications.
