Continuous infusion intermediate-dose cytarabine, mitoxantrone, plus etoposide for refractory or early relapsed acute myelogenous leukemia

A budget impact analysis of gilteritinib for the treatment of relapsed or refractory FLT3 mut+ acute myeloid leukemia in a US health plan

AIMS

To estimate the economic impact of the introduction of gilteritinib for the treatment of relapsed/refractory (R/R) FLT3 mutation-positive (FLT3 ^mut+) acute myeloid leukemia (AML) from a US payer's perspective.

METHODS

A budget impact model (BIM) was developed to evaluate the 3-year total budgetary impact of treating adults with R/R FLT3 ^mut+ AML eligible for gilteritinib in a hypothetical US health plan. Total costs (drugs/administration, hospitalization, monitoring, adverse events, transfusions, subsequent hematopoietic stem cell transplantation, post-progression, and FLT3 testing) were estimated before and after gilteritinib entry. The budget impact was the total cost difference between the two scenarios. The target population size and cost inputs were based on public data or published literature, drug market share was informed by market research data, and the model included recommended treatments for R/R FLT3 ^mut+ AML per clinical guidelines. Deterministic sensitivity analyses (DSAs) and scenario analyses varying key model inputs and assumptions were conducted to test for robustness.

RESULTS

In a hypothetical health plan with 1 million members, 20.9 adults with R/R FLT3 ^mut+ AML were estimated to be eligible for gilteritinib. Of these, it was assumed 30.0% would be treated with gilteritinib in Year 1 following gilteritinib entry, increasing the total plan budget by $663,795 and the per-member-per-month (PMPM) cost by $0.055. In Years 2-3, the market share of gilteritinib increased to 45.0%, increasing the total plan budget impact by $1,078,371 and $1,087,230, and the PMPM cost by $0.090 and $0.091, respectively. The model results remained robust in DSAs and scenario analyses, with the largest impact observed when the projected uptake of gilteritinib was changed.

LIMITATIONS

The results of this BIM are contingent upon the model's assumptions and inputs.

CONCLUSIONS

Adding gilteritinib to the formulary for the treatment of adults with R/R FLT3 ^mut+ AML had a minimal budget impact from a US payer's perspective.

Clonal dynamics in a single AML case tracked for 9 years reveals the complexity of leukemia progression

Most types of cancers are made up of heterogeneous mixtures of genetically distinct subclones. In particular, acute myeloid leukemia (AML) has been shown to undergo substantial clonal evolution over the course of the disease. AML tends to harbor fewer mutations than solid tumors, making it challenging to infer clonal structure. Here, we present a 9-year, whole-exome sequencing study of a single case at 12 time points, from the initial diagnosis until a fourth relapse, including 6 remission samples in between. To the best of our knowledge, it covers the longest time span of any data set of its kind. We used these time series data to track the hierarchy and order of variant acquisition, and subsequently analyzed the evolution of somatic variants to infer clonal structure. From this, we postulate the development and extinction of subclones, as well as their anticorrelated expansion via varying drug responses. In particular, we show that new subclones started appearing after the first complete remission. The presence and absence of different subclones during remission and relapses implies differing drug responses among subclones. Our study shows that time series analysis contrasting remission and relapse periods provides a much more comprehensive view of clonal structure and evolution.

A prospective, multicenter phase II study of continuous infusion of FLAG for patients older than 60 yr with resistant acute myeloid leukemia: a comparison with intensive younger patients' trial

Relapsed or refractory acute myeloid leukemia (R/R AML) in elderly (≥60 yr old) patients were eligible. Induction chemotherapy consisted fludarabine and cytarabine (ARAC) as a 24-hr CI without idarubicin (C-FLAG), which was compared with the results of C-FLAG with idarubicin (CI-FLAG2) in younger patients' trial. A total of 33 and 68 patients were enrolled in C-FLAG and CI-FLAG2, respectively. CR, CRp, and CRi were achieved in 10 (30.3%), 3 (9.1%), and 2 (6.1%), respectively. When comparing outcomes between C-FLAG and CI-FLAG2, there were no difference in terms of CR rate (P = 0.572) and objective response rate (ORR; P = 0.899). Favorable predictors on ORR in C-FLAG were PB WBC ≤ 20K/uL at salvage (P = 0.024) and early evaluation peripheral BLAST = 0% (P = 0.013) on multivariate analysis. The overall survival of patients who achieve CR/CRp/CRi showed significantly prolonged survival compared with patients who did not in C-FLAG (P < 0.001) and was a favorable predictor of longer survival by multivariate analysis (P = 0.009). Median overall survival was 3.19 (95% CI, 2.05-4.33) months and similar with that of CI-FLAG2 (P = 0.841). Attenuated salvage regimen C-FLGA in elderly patients was as effective as more intensive younger patients' regimen CI-FLAG2 in terms of response and survival although elderly patients had more unfavorable clinical characteristics.

Prospective, multicenter, phase II study on reducing the dosage of idarubicin and FLAG for patients younger than 65 years with resistant acute myeloid leukemia: a comparison with a higher dosage trial

We previously assessed continuous infusion (CI) of fludarabine and cytarabine plus idarubicin (CI-FLAG1) for patients under 65 years of age with resistant acute myeloid leukemia. Induction chemotherapy consisted of idarubicin (IDA) plus fludarabine and cytarabine (ARAC) as a 24-hour CI. In response to induction, 31.6% of patients achieved complete remission (CR) and in 68.4% the treatment failed. We concluded that CI-FLAG1 carried a high risk of toxicity and reduced CI-FLAG doses were recommended. Therefore, we revised the protocol (CI-FLAG2) by reducing the dose of IDA and ARAC. In total, 38 and 68 patients were enrolled into CI-FLAG1 and CI-FLAG2, respectively. When comparing outcomes between CI-FLAG1 and CI-FLAG2, there were no differences in terms of the CR rate (p = 0.306) and the overall response rate (ORR; p = 0.206). The treatment failure patterns were different between CI-FLAG1 and CI-FLAG2. The median overall survival showed only a trend towards longer survival in CI-FLAG2 (p = 0.074). Among intermediate-risk patients, there were high response rates favoring CI-FLAG2 in terms of the CR rate (p = 0.108), the ORR (p = 0.031), and overall survival (p = 0.033). This represented a relatively improved response rate compared to our previous study. There was decreased aplasia with dose reductions at the expense of increased resistance. A reduced dose of CI-FLAG might be most beneficial for intermediate-risk groups.

Allogeneic hematopoietic cell transplantation for acute leukemia in first relapse or second remission

Background

The role of pre-transplant salvage chemotherapy has been controversial in relapsed acute leukemia.

Methods

We investigated post-transplant outcomes in 65 patients with acute leukemia treated with allogeneic hematopoietic cell transplantation (HCT) during first relapse or second remission.

Results

The 5-year cumulative incidence of relapse (CIR) was 52.3%. Multivariate analysis for CIR revealed that patients with unfavorable cytogenetics and those not in remission at the time of HCT had a significantly high CIR (P = 0.031 and P = 0.031, respectively). Allogeneic HCT was performed in 14 patients after first relapse without salvage chemotherapy ("untreated relapse" group), 15 patients failed chemotherapy for reinduction of remission before HCT ("refractory relapse" group), and 36 patients attained second remission with salvage chemotherapy before HCT ("second remission" group). The 5-year CIR for patients in the untreated relapse group (57.1%) was higher than that for those in the second remission group (42.3%), but it was lower than that for patients in the refractory relapse group (66.7%). Among patients who underwent allogeneic HCT in relapse, those with bone marrow (BM) blasts ≤30% had a lower 5-year CIR than those in florid relapse (BM blasts >30%) (57.7% vs. 70.6%).

Conclusion

Our results do not support the role of salvage chemotherapy aimed at re-induction of remission before allogeneic HCT in patients with acute leukemia after first relapse. Patients with early relapse do not appear to benefit from salvage chemotherapy before HCT.

Continuous infusion of intermediate-dose cytarabine and fludarabine with idarubicin for patients younger than 60 years with resistant acute myeloid leukemia: a prospective, multicenter phase II study

We assessed continuous infusion (CI) of fludarabine and cytarabine (FLAG) plus idarubicin for patients under 60-years old with resistant acute myeloid leukemia (AML). Induction chemotherapy consisted of idarubicin (12 mg/m(2) iv infusion over 30 min on Days 1-3), plus fludarabine (30 mg/m2/day) and cytarabine (1,000 mg/m(2)/day) on Days 1-5 as a 24-hr CI. G-CSF was added on Days 1-5. The 29 patients enrolled were of median age 40 years (range, 18-57 years); of these, 8 (27.6%) had primary refractory disease, 19 (65.5%) were in early relapse, and 1 each (3.4%) was in multiple relapse and relapse after SCT. In response to induction, 8 patients (27.6%) achieved CR, 2 (6.9%) achieved CRp, and 19 (65.5%) failed treatment; of the latter, 14 had aplasia, three had an indeterminate course, and two showed resistance. Seven patients remain alive, while two were lost to follow-up. Nineteen patients died, 14 of infection, one of toxicity during consolidation, three of relapse after SCT, and two of persistent disease. These findings indicate that although CI of FLAG plus idarubicin was effective for eradicating blasts, it carried a high risk of toxicity. Reduced doses are recommended for CI of FLAG plus idarubicin.

Novel strategies for relapsed and refractory acute myeloid leukemia

PURPOSE OF REVIEW

Treatment for relapsed or refractory acute myeloid leukemia remains a major challenge for the leukemia community. Although several approaches have been tested in phase II study designs, few comparative data exist to guide treatment choices. We searched the recent literature in Medline, EMBASE and BIOSIS, and abstracts from the American Society of Hematology and American Society of Clinical Oncology published between 2005 and 2007. We reviewed each report to identify studies that used a phase II or III design and that included a majority of adults with non-M3 acute myeloid leukemia described as 'relapsed' or 'refractory'.

RECENT FINDINGS

Several studies utilized novel cytotoxic chemotherapies, immunotherapies, epigenetic agents, and small molecule inhibitors. It is not possible to identify a single regimen or approach as the standard of care in relapsed and refractory acute myeloid leukemia. New and promising approaches are being explored, however.

SUMMARY

Outcomes in patients treated for relapsed or refractory acute myeloid leukemia remain inadequate. Striking a balance between the treatment-related mortality associated with salvage therapies, response rates of salvage regimens, and the likelihood of long-term disease-free survival are critical in planning a treatment approach for the individual patient with relapsed or refractory acute myeloid leukemia.

Gemtuzumab ozogamicin with cytarabine and mitoxantrone as a third-line treatment in a poor prognosis group of adult acute myeloid leukemia patients: a single-center experience

We analyzed the safety and efficacy of gemtuzumab ozogamicin (GO) combined with cytarabine and mitoxantrone in the treatment of 21 patients with acute myeloid leukemia (11 refractory and 10 in second relapse). Patients' median age was 52 years (range 36-68); all patients had previously been treated with anthracycline-containing regimens (daunorubicin and idarubicin). GO at a dosage of 3 mg/m2 was administered as a 2-h intravenous infusion on days 1 and 14, cytarabine at 100 mg/m2 on days 1-7, and mitoxantrone at 12 mg/m2 on days 1-3. Infusion-related events were observed in 15 of 21 (71.4%) patients. The incidence of grade 1 or 2 elevations of bilirubin and hepatic transaminases was 4 of 21 (19%) and 3 of 21 (14.2%). In response to chemotherapy, 2 of 21 (9.5%) achieved complete remission and 2 of 21 (9.5%) achieved complete remission with incomplete platelet recovery, with an overall remission rate of 4 of 21(19%); median survival of these 4 patients was 7 months. Four of 21 patients (19%) died during aplasia after chemotherapy; no veno-occlusive disease occurred. No treatment-related cardiotoxicity or cerebellar toxicity was observed. In our experience, the addition of GO to mitoxantrone and cytarabine is feasible in refractory or second relapse acute myeloid leukemia patients but yields a low response rate when used as a third-line treatment.