Frontline Flumatinib Shows Comparable Safety, Superior Efficacy to Imatinib in Newly-Diagnosed CML
Chicago, Illinois—For patients with newly-diagnosed chronic myeloid leukemia in chronic phase (CML-CP), flumatinib demonstrated comparable safety and superior efficacy to imatinib at various time points, supporting its use in the front-line treatment of this patient population, according to study results presented at the 2019 ASCO Annual Meeting.
The open-label phase III study by Zhang Li, MD, State Key Laboratory of Experimental Hematology, Institute of Hematology, Chinese Academy of Medical Sciences, Tianjin, China, et al aimed to validate the efficacy and safety of flumatinib in comparison with imatinib as front-line treatment for patients with newly-diagnosed Philadelphia-positive CML-CP.
The primary end points of the study were major molecular response rates (MMR) at 6 and 12 months. Patients in the intention-to-treat population were used to analyze efficacy end points.
Although 400 eligible patients were randomized for treatment by Sokal score, the full analysis set comprised 393 patients who received flumatinib 600 mg (n = 196) or imatinib 400 mg (n = 197) once daily.
Recipients of flumatinib had significantly higher induction of MMR rate at 6 months (33.7%; 95% CI, 27.06-40.29 vs 18.3%; 95% CI, 12.88-23.67; P = .0005), 12 months (48.5%; 41.47-55.47 vs 33.0; 26.43-39.56; P = 0.0021), and even at 3 months (8.2; 95% CI, 4.33-12.00 vs 2.0%; 95% CI, 0.06-4.00; P = .0058) than those given imatinib.
In addition, there were significantly more patients in the flumatinib versus imatinib arms who achieved a complete molecular response at 12 months. Findings also demonstrated early molecular response at 3 months and early CCyR at 6 months that were significantly higher in the flumatinib versus imatinib arms (82.1%; 95% CI, 76.78-87.50 vs 53.3%; 95% CI, 46.33-60.27; P <.0001 and 60.71%; 95% CI, 53.88-67.55 vs 49.75%; 95% CI, 42.76-56.73; P = .0332).
In terms of safety, the profiles of flumatinib and imatinib were deemed similar by the investigators. Rates of grade 3/4 treatment-emergent adverse events were comparable between arms, with 112 (56.57%) occurring in recipients of flumatinib and 87 (41.38%) occurring in recipients of imatinib.
Notably, however, the frequencies of certain nonhematologic and hematologic adverse events were significantly lower with flumatinib than with imatinib, including rash (4.59% vs 12.63%, respectively; P = .0064), eyelid edema (0.51% vs 14.65%; P <.0001), leukopenia (30.61% vs 62.63%; P <.0001), and neutropenia (30.10% vs 59.60%; P <.0001). There were no specific treatment-emergent adverse events identified in either therapy arm.
“Our study results suggest that FM [flumatinib] is comparable to IM [imatinib] in its safety and superior in its efficacy profile at 3, 6 and 12 month time points. These results support FM as a frontline treatment option for patients with newly diagnosed CML-CP,” Dr Li and colleagues concluded.—Janelle Bradley
Li Z, Meng L, Zhang Y, et al. Frontline flumatinib versus imatinib in patients with chronic myeloid leukemia in chronic phase: Results from the China randomized phase III study. Presented at: the 2019 ASCO Annual Meeting; May 31-June 4, 2019; Chicago, IL. Abstract 7004.
