A new study characterized real-world renal function and outcomes for patients with multiple myeloma (MM) according to type of treatment and line of therapy. The study results were published in Blood Cancer Journal as a correspondence by Joseph Mikhael, MD, of Translational Genomics Research Institute and City of Hope Cancer Center in Phoenix, AZ, and colleagues.
The study was based on patient records in the Flatiron Health database from approximately 2880 cancer clinics. Analyses included data from 6990 patients who had received 1 or more lines of therapy for MM. Renal function in was measured using the estimated glomerular filtration rate (eGFR)-Modification of Diet in Renal Disease (MDRD) equation. Overall survival (OS) was assessed for patients according to treatment line and stratified by the baseline eGFR-MDRD level. Complete renal response (CRR) with a treatment line was defined as having 1 or more eGFR-MDRD measurements of ≥60 mL/min/1.73 m2.
At the start of first-line therapy, one-fourth of the patients demonstrated an eGFR-MDRD of <50 mL/min/1.73 m2. Half of the patients had an eGFR-MDRD of ≥50 mL/min/1.73 m2, while for the rest of the patients the eGFR-MDRD was not known.
Patients who had an eGFR-MDRD of <50 mL/min/1.73 m2 showed poorer OS with first-line and second-line therapies than did patients in the higher eGFR-MDRD group. In multivariable analysis, for first-line therapy, the adjusted hazard ratio (HR) for OS for this comparison was 1.58 (95% CI, 1.43-1.73), and for second-line therapy it was 1.49 (95% CI, 1.33-1.68).
For evaluable patients who had an eGFR-MDRD of <50 mL/min/1.73 m2 at the beginning of first-line therapy, the CRR rate was 38.5% with initial therapy and 19% with second-line therapy. Most patients with this level of renal function had used proteasome inhibitor (PI) therapy in first- and second-line treatment.
Treatment with an immunomodulatory drug (IMiD) in first and second lines was seen with approximately half of the patients who showed renal impairment. PI therapy and IMiD therapy were each linked to a significantly greater likelihood of achieving CRR in the first and second lines for patients with this level of renal function.
Overall, combined use of PI and IMiD therapies was associated with significantly improved OS in both first and second lines for patients who achieved CRR, in comparison with patients who did not receive either type of therapy and did not achieve CRR in first and second lines of therapy. Combined use of these treatment classes was also associated with higher rates of CRR in early lines of therapy. Analyses involving the use of monoclonal antibodies were limited by their low usage during early treatment lines.
“Overall, these data suggest that using combination therapy early with the goal of inducing a renal response in these patients is not only feasible, but also may result in improved outcomes,” Dr Mikhael and colleagues concluded in their report.
Disclosures: Some authors have declared affiliations with or received grant support from the pharmaceutical industry. Please refer to the original study for a full list of disclosures.
Mikhael J, Singh E, Rice MS. Real-world renal function among patients with multiple myeloma in the United States. Blood Cancer J. 2021;11(5):99. doi:10.1038/s41408-021-00492-6