Novel Antibody-Drug Conjugate Under Study in Resistant Multiple Myeloma
Posted: Friday, May 29, 2020
According to phase I study findings published in Clinical Cancer Research, the antibody-drug conjugate ABBV-838 seems to be safe and well tolerated in patients with relapsed and refractory multiple myeloma. However, the first-in-human study, conducted by Ravi Vij, MD, of Washington University School of Medicine, St. Louis, and colleagues, also found the treatment to be of limited efficacy.
“While ABBV-838 showed promising results in preclinical models, ABBV-838 treatment did not translate into substantial clinical benefit in patients with relapsed and refractory multiple myeloma,” the investigators commented.
A total of 75 patients with relapsed and refractory multiple myeloma received between 0.6 mg/kg and 6.0 mg/kg of intravenous ABBV-838 every 3 weeks, for a maximum of 24 months. During the study, 73.3% of patients experienced treatment-emergent adverse events of grade 3, 4, or 5, most commonly neutropenia (20.0%), anemia (18.7%), and leukopenia (13.3%). About 40% of patients experienced grade 3, 4, or 5 events related to ABBV-838. Among patients experiencing treatment-emergent adverse events, 4.0% died, none of ABBV-833–related events. Of all treatment-emergent adverse events reported in the study, the most common were neutropenia (28.0%), anemia (28.0%), fatigue (26.7%), and nausea (25.3%).
The overall response rate was 10.7%, with 2.7% of patients and 8.0% of patients achieving very good partial responses and partial responses, respectively. The maximum tolerated dosage of ABBV-838 was not reached. The recommended dose was 5.0 mg/kg for those in an expansion cohort of the study.
“Further investigations may be required to determine the reasons for the limited antitumor activity of ABBV-838,” the researchers concluded.
Disclosure: For full disclosures of the study authors, visit clincancerres.aacrjournals.org.
