For elderly patients with chronic lymphocytic leukemia (CLL) and comorbidities, the anti-CD20 monoclonal antibody ofatumumab may be a safe and effective treatment option, according to a recent phase 2 trial.
Among 32 patients with a median age of 73 years, the overall response rate was 72%, and no grade 4 adverse events occurred, reported lead author Candida Vitale, MD, PhD, of the University of Torino (Italy) and colleagues.
These findings help fill in a knowledge gap created by clinical trial exclusions, which currently make treatment planning “a significant challenge,” the investigators wrote in Journal of Geriatric Oncology.
The study, which was conducted at MD Anderson Cancer Center in Houston, enrolled 34 treatment-naive patients with CLL who were 65 years or older. All patients had an Eastern Cooperative Oncology Group performance status of 2 or 3, or a Charlson comorbidity index of at least 2. Patients with other serious medical conditions and/or primary malignancies were eligible, given that they were not already receiving anticancer therapy.
More than half of the patients (53%) had advanced-stage disease and almost one-third (29%) had at least one other primary cancer diagnosis. Many patients also had high-risk disease characteristics, including a complex karyotype involving three or more chromosomal abnormalities (15%), and/or unmutated immunoglobulin heavy chain variable region (IGHV, 59%).
Among 32 patients eligible for efficacy analysis, the overall response rate was 72%, of which 53% were partial and 19% were complete. Six percent (6%) of patients achieved minimal residual disease negativity. The benefits of ofatumumab extended to patients with high-risk disease characteristics, including unmutated IGHV (65% response rate) and/or a complex karyotype (60% response rate).
Ofatumumab also demonstrated a favorable safety profile, according to the investigators.
With all 34 patients evaluable for safety data, 19 (56%) experienced a grade 1 or 2 infusion-related reaction, and 1 (3%) experienced a grade 3 infusion-related reaction. Twenty-one grade 2 infections were reported, and one grade 3 infection occurred. Other grade 3 treatment-related adverse events included gastrointestinal disturbances, pulmonary embolism, allergic reaction, and hyperglycemia, each of which occurred in one patient. No grade 4 adverse events, or grade 2 or higher hematologic toxicities occurred.
“Our findings show that older patients with poor performance status and comorbidities can safely undergo treatment with ofatumumab,” the investigators concluded. “[The results] also support the possibility of enrolling these patients in clinical trials, so that a larger number of patients will be included and their characteristics will more closely mirror those of typical patients seen in the community.”
The study was funded by Novartis, which markets the antibody. The investigators reported additional relationships with AbbVie, Roche, Celgene, and others.
SOURCE: Vitale et al. J Geriatr Oncol. 2019 Apr 18. doi: 10.1016/j.jgo.2019.04.002.