Cancer Therapy Leukemia Instrument Shows Promise for AML Clinical Trials

July 14, 2020

FACT-Leu was found to be a suitable outcome measure for patients not eligible for intensive therapy in acute myeloid leukemia clinical trials.

A functional assessment of FACT-Leu, published in Cancer, found that the cancer therapy leukemia instrument is a suitable outcome measure for patients not eligible for intensive therapy in acute myeloid leukemia (AML) clinical trials and may also have value for clinical monitoring.

According to the researchers, the overall study findings suggested that tools like FACT-Leu play an important role in helping oncology grow increasingly patient-centered.

“Although this study’s sample was restricted to patients with AML who were not candidates for intensive therapy, our analyses supporting the FACT-Leu’s validity among these patients have significant implications,” the authors wrote.

Using a sample of 317 patients with AML who were not eligible for intensive chemotherapy, researchers had participants complete the FACT-Leu and EuroQol 5-Dimension (EQ-5D) measures every 28 days until the end of treatment. The study evaluated responsiveness to change by anchoring change in the FACT-Leu scales to a 0.10 change in the EQ-5D Health Utility Index. Of note, internal consistency reliability was estimated using Cronbach’s α.

In the study, Cronbach's α usually exceeded the threshold for good (≥0.80) or excellent reliability (≥0.90). Moreover, the associations between FACT-Leu and EQ-5D scales were moderate (r > 0.50) or high (r > 0.70).

FACT-Leu scales were found to effectively differentiate between Eastern Cooperative Oncology Group (ECOG) performance status ratings (PSR) groups with large effect sizes for an ECOG PSR of 0 versus an ECOG PSR of 2 (0.50 ≤ d < 0.80). Additionally, Functional Assessment of Cancer Therapy – General, Additional Concerns, FACT-Leu Total, and Trial Outcomes Index scales discerned differences between patients with grade 3 or lower maximum adverse event toxicities and those with maximum adverse event toxicities higher than grade 3, though effect sizes were small (d < 0.50).

Ultimately, FACT-Leu scale coefficients for a 0.10 change in the 5-level version of the EQ-5D HUI ranged between -0.01 and 4.30.

“Perhaps most notably in this study, the FACT-Leu evidenced responsiveness to changes in health among patients with AML who were not eligible for intensive therapy,” the authors wrote. “For this reason, this article’s results support the use of the FACT-Leu in clinical trials focusing on AML.”

Notably, since the data used for analysis in this study were from a clinical trial among patients with newly diagnosed AML who were not eligible for intensive therapy and who were older than 50 years, the study was not designed to be representative of a larger population of patients with AML. Given this, the researchers suggested that future studies representative of the AML populations of interest (e.g., national populations) should be conducted to confirm these findings and to generate normative reference values for the FACT-Leu scales.

Even further, though multiple variables were available for validity analyses, the investigators indicated that longitudinal measurement of the ECOG performance status would have enhanced the analysis of responsiveness to changes in health. Therefore, additional research should focus on a design which allows more analyses of the FACT-Leu’s responsiveness to changes among this patient population. 

“There is an urgent need for methodologically sound prospective HRQOL studies in patients with AML to generate data that can facilitate the establishment of criteria for nonsurvival clinical benefits of AML therapies,” the authors wrote. “To this end, we propose that the implementation of the FACT-Leu in future AML trials might help to bridge this gap and eventually facilitate integration of [health-related quality of life; HRQOL] as a valuable treatment endpoint.”

Reference:

Peipert JD, Yount SE, Efficace F, Loefgren C, Pierson R, He J, Cella D. Validation of the Functional Assessment of Cancer Therapy– Leukemia Instrument in Patients with Acute Myeloid Leukemia Who Are Not Candidates for Intensive Therapy. Cancer. doi:10.1002/cncr.32977.