A Comparison of Clofarabine-based (GCLAC) and Cladribine-based (CLAG) Salvage Chemotherapy for Relapsed/Refractory AML
Salvage regimens for patients with relapsed/refractory acute myeloid leukemia (rrAML) lack comparative data for superiority. Thus, we conducted a retrospective analysis of clofarabine-based (GCLAC; granulocyte colony-stimulating factor [filgrastim], clofarabine, high-dose cytarabine) versus cladribine-based (CLAG; cladribine, cytarabine, granulocyte colony-stimulating factor [filgrastim]) regimens in rrAML.Patients and Methods
We identified 41 consecutive patients with rrAML who had received either GCLAC or CLAG from 2011 to 2014. The primary outcome measure was the complete remission (CR) rate defined according to the International Working Group criteria. The secondary outcomes included the proportion of patients who underwent allogenic stem cell transplantation and the rate of relapse-free survival and overall survival.Results
We found no significant differences in the baseline characteristics of the patients treated with GCLAC (n = 22) or CLAG (n = 19). The outcomes with these 2 regimens were not significantly different. Patients treated with GCLAC had a CR/CR with incomplete blood count recovery rate of 64% compared with 47% for the patients treated with CLAG (P = .36). Of the GCLAC patients, 45% underwent allogeneic stem cell transplantation compared with 26% of the CLAG patients (P = .32). The median relapse-free survival after GCLAC and CLAG was 1.59 years and 1.03 years, respectively (P = .75). The median overall survival after GCLAG and CLAG was 1.03 years and 0.70 years, respectively (P = .08). The drug costs were significantly different for GCLAC versus CLAG. Using an average wholesale price, the cost per patient per cycle was $60,821.60 for GCLAC and $4910.60 for CLAG.Conclusion
A single-institutional retrospective analysis found no significant differences in the outcomes between GCLAC and CLAG for rrAML patients, although formal comparisons should be performed in a randomized clinical trial. The cost of GCLAC was greater than that of CLAG, which should be considered when evaluating the choice for the salvage chemotherapy options.Micro-Abstract
The data for savage regimens in relapsed/refractory AML is largely based on phase 2, single arm studies and comparative data is scarce. The purpose of this retrospective study was to compare two salvage AML chemotherapy regimens, GCLAC (clofarabine-based) and CLAG (cladribine based) in 41 patients (22 and 19 in each arm, respectively). There were no statistically significant differences in complete response rates (GCLAC = 64%; CLAG = 47%, P = .36) as well as other endpoints including safety endpoints. GCLAC was associated with significantly higher costs compared with CLAG ($60,821.60 vs $4910.60 per cycle using AWP pricing, respectively).