ADC Therapeutics (ADCT) has started a Phase I trial of its lead antibody drug conjugate (ADC) ADCT-301, a potential treatment for patients with acute myeloid leukaemia (AML).
The trial is designed to evaluate the tolerability, safety, pharmacokinetics and activity of ADCT-301 in patients with relapsed or refractory CD-25 positive AML.
ADCT-301 is composed of HuMax-TAC, a monoclonal antibody directed against the alpha chain of the IL-2 receptor (CD25) and conjugated to the company’s potent proprietary pyrrolobenzodiazepine (PBD) dimer.
Around 30 patients will be enroled in the initial dose escalation phase at ten clinical sites across the US.
This will determine the recommended dose of ADCT-301 for the second stage, which will be expanded with 30 additional patients in the UK and Europe.
The company noted that in preclinical in vivo models, ADCT-301 exhibited strong dose-dependent anti-tumour activity against CD25-positive cell lines at low doses.
Memorial Sloan Kettering Cancer Center Leukemia Service chief and principle Investigator of the trial Martin Tallman said: "Acute myeloid leukemia is the most common leukemia in the US adult population and the prognosis is poor. Patients expressing CD25 on their leukaemia cells have a particularly poor prognosis.
"ADCT-301 has shown promise in in vivo studies and we believe that this important trial could help us to improve patient outcomes."
The company currently has two PBD-based ADCs in four clinical trials, with four other ADCs in late preclinical development and further ADCs being researched.
ADC Therapeutics CEO Dr Chris Martin said: "Dosing the first patient in this trial with ADCT-301 is an important milestone for the company.
"We look forward to the progress of this trial over the coming year and to accelerating the clinical development of our ADC pipeline."
Image: Bone marrow aspirate showing acute myeloid leukaemia. Photo: courtesy of VashiDonsk.