Treatment with 5-Azacytidine in High Risk MDS, CMML and AML: A Single Center Analysis with Regard to Days in Hospital and Days in Outpatient Clinic

Introduction: Patients with high risk MDS, CMML or AML are suffering from low cell counts and as a consequence are at higher risk for infections and bleeding. Treatment with 5-Azacytidine is the only approved treatment for patients with high risk MDS, dysplastic CMML and AML who are not candidates for allogeneic stem cell transplantation in Europe. As the compound is administered in specialized facilities and not at home, patients have to visit the hospital or outpatient clinic at least seven days per month. In this retrospective study, we try to analyze how many days the patients visited our outpatient clinic as well as how many days the patients spent in hospital due to administration of the compound, due to complications such as infections and bleeding, or due to other reasons.

Methods: Clinical data of 221 patients who were treated at our department either because of high risk MDS, dysplastic CMML, or AML were retrieved from the Düsseldorf MDS Registry. Patients were followed up till June 30^th 2024. Overall survival was assessed using the Kaplan-Meier method.

Results: The data included 144 patients with MDS (65.1%), 18 with CMML (8.1%), and 59 with AML (26.6%). 167 patients (75.6) were de novo diseases. At the start of treatment there were 113 patients with MDS (51.1%), 13 patients with CMML (5.9%), and 95 patients with AML (43%). 15% of the patients with MDS were allocated to the intermediate risk group according to the IPSSR, 44% to the high risk group, 36% to the very high risk group, and in 6% the IPSSR was unknown. 3% of the patients with AML were allocated to the low risk group according to the ELN, 31% to the intermediate group, 47% to the high risk group and in 19% the exact EKN group was unknown. Median age at the start of treatment was 72 years (60-88). 138 patients were male (62.4%). 205 patients (92.3%) died during the observation period. 56.7% died due to infection, 2.8% due to bleeding, 22% due to progression of the disease, 3.5 % due to cardiovascular events, 0.7% due to cancer, and in 14.2% the exact cause of death could not be assessed. ECOG at start of treatment was 0 in 9.5%, 1 in 59.3%, 2 in 6.8%, and 3 in 1.8%. Median time from first diagnosis to start of treatment was 1 months (0-151). Median overall survival (OS) from start of treatment was 10 months (1-93). OS of patients with MDS was 11 months, CMML 15 months, and AML 7 months (0=0.01). Median contacts to the outpatient department for whatever reason was 32 (0-393). Median contacts for injection of the compound was 17 (0-250), for transfusions 1 (0-74), for i.v. antibiotics or antifungals 0 (0-27). In house hospitalization from the start of treatment with 5-Azacytidine was necessary in 94% of the patients, in 85% due to disease-related complications such as infections or bleeding, and 41% due to other not disease related reasons. The median number of days in hospital was 33 (0-222). Median number of days in hospital due to disease related reasons was 28 (0-222), whereas median number of days in hospital due to other reasons was 0 (0-180).

As the median survival time from start of treatment was 330 days, the patients spend 10% (0-100) of these days in hospital and had to show up additionally in our outpatient department on 10% of the remaining days. In 20% of the days after start of treatment, patients either were hospitalized or had to contact the outpatient department.

Conclusion: Patients with high risk MDS, CMML or AML treated with 5- Azacytidine spend a considerable part of the treatment course in hospital or in outpatient clinics in part just for the administration of the drug. Oral administration of hypomethylating agents could extend the time at home available to those patients.

Czerwensky:Otsuka Pharma GmbH: Current Employment. Germing:BMS: Research Funding; JAZZ: Research Funding; Novatis: Honoraria; BMS: Honoraria; Abbvie: Research Funding.