A real-world, retrospective, observational study examining treatment patterns and clinical outcomes in patients with FLT3m + AML in Japan

Abstract

Objective

Acute myeloid leukemia (AML) is the most common form of leukemia among adults in Japan. This study aimed to understand the treatment patterns, health care resource utilization, and costs of FMS-like tyrosine kinase 3 mutation-positive (FLT3m+) AML patients in Japan.

Methods

A retrospective cohort study of Japanese FLT3m + AML patients was conducted using data extracted from a national hospital-based claims database provided by Medical Data Vision Co. Ltd. (MDV; Tokyo, Japan). Patients were identified from the MDV database between April 2008 and April 2021 inclusive.

Results

A total of 360 patients were included in this study. The study results suggest that cytarabine + anthracyclines was the most common first-line (1 L) treatment, accounting for 41.3% of the patients. FLT3 inhibitors (FLT3i) was the most common treatment across the study period (95.7%). The mean age of patients was 62.4 years, and most were 65 years or older. The median overall survival (OS) after initiating FLT3i treatment was 394 days. The median treatment duration of FLT3i was 88.5 days, while it was 66.0 days for patients treated with FLT3i within 60 days after hematopoietic stem cell transplantation (HSCT). The overall mean monthly total treatment cost was JPY 2,009,531.7/per patient per month (PPPM) (USD 17,967.9/PPPM).

Conclusions

The study found specific treatment patterns, trends and features in patients with FLT3m + AML. FLT3i was the most prescribed treatment across the study period and the overall median OS after initiating FLT3i treatment was over 1 year. The findings of this study could be helpful for clinicians to optimize treatment strategies for FLT3m + AML in Japan.

Graphical Abstract

Keywords:

• FLT3m + AML
• chemotherapy
• allogeneic HSCT
• FLT3i
• cytarabine
• anthracycline

Transparency

Declaration of funding

This study was sponsored by Astellas Pharma Inc.

Declaration of financial/other relationships

TK received grants or contracts from Daiichi-Sankyo, Janssen, Otsuka, and SymBio and payment or honoraria for lectures from Bristol-Myers Squibb, Novartis, and SymBio. MS, TM, YT, and KK are employees of Astellas. KY and SS are employees of IQVIA Solutions Japan KK. Peer reviewers on this manuscript have no relevant financial or other relationships to disclose.

Author contributions

TK, MS, YT, KK, and YK made substantial contributions to the study design; TK, MS, TM, YT, KK, YK, and SS acquired the study data; TK, MS, TM, YT, KK, YK, and SS analyzed the study data; TK, MS, TM, YT, KK, YK, and SS interpreted the study data.

Acknowledgements

Medical writing support was provided by Dipti Mothay and Rosario Vivek from IQVIA India, and Dilinuer Ainiwaer from IQVIA Solutions Japan. Editorial assistance was provided by Todd D. Taylor, IQVIA Solutions, Japan.

Data availability statement

Researchers may request access to anonymized participant-level data, trial-level data, and protocols from Astellas-sponsored clinical trials at www.clinicalstudydatarequest.com.

For the Astellas criteria on data sharing, see: https://clinicalstudydatarequest.com/Study-Sponsors/Study-Sponsors-Astellas.aspx.