Patients with acute myeloid leukemia (AML) whose disease relapsed or did not respond to initial chemotherapy had similar outcomes when they proceeded directly to allogeneic stem cell transplantation compared with those who underwent intensive salvage chemotherapy to achieve complete remission first, according to a recent clinical trial. The findings seem to run counter to the common practice of offering stem cell transplantation solely to patients who are in complete remission and suggest many patients may be able to skip the additional step of salvage chemotherapy before receiving a transplant. These findings were presented by Stelljes et al at the 2022 American Society of Hematology (ASH) Annual Meeting and Exposition (Abstract 4).
“Allogeneic stem cell transplantation is a very potent strategy that is curative for many patients,” said senior study author Johannes Schetelig, MD, MSc, of the University of Dresden, Germany. “Our study suggests that the international standard of bringing patients into remission first should be questioned, as it proves that allotransplant should be considered a standard treatment option even for patients with active disease.”
Study Background and Details
Previous research has shown that patients fare better in the long run if they achieve complete remission before receiving a stem cell transplant, but most studies have examined the question retrospectively. The recent study is the first randomized trial to assess whether salvage chemotherapy makes a difference in long-term outcomes after stem cell transplantation.
Researchers enrolled 281 patients treated for relapsed or refractory AML in Germany. Half proceeded directly to stem cell transplantation, and half underwent salvage chemotherapy first. The median time from random assignment to transplantation was 4 weeks among those proceeding directly to transplantation and 8 weeks among those receiving salvage chemotherapy. Researchers tracked outcomes for a median of about 3 years.
Key Results
The two study groups showed similar outcomes in all key endpoints. The primary endpoint, complete remission at day 56 after transplantation, was achieved in 84.1% of patients in the direct-to-transplant arm and 81.3% of patients in the salvage chemotherapy arm. The groups also had similar rates of overall survival at 1 year (around 70% for both groups) and 3 years (a bit more than 50%) after random assignment. Among patients who were in complete remission at day 56, the two groups also had similar rates of leukemia-free survival at 1 year.
“We were astonished—we never expected these results,” Dr. Schetelig said. “Patients did not gain additional benefit from salvage chemotherapy at all. It suggests we should think about starting the process of allotransplantation as soon as possible.”
Researchers say the findings are likely to come as welcome news for patients and families, as skipping the step of salvage chemotherapy would mean avoiding the added burden of several weeks in the hospital as well as the cost and toxicity associated with that additional treatment. The findings could also increase the number of people eligible for stem cell transplantation.
The findings were consistent across subgroups, although researchers are continuing to analyze the data to determine whether certain subgroups of patients are more likely to benefit from one strategy vs the other. Although achieving a complete remission after transplantation is within reach for the majority of patients, future research should focus on maintaining disease control over the long term, Dr. Schetelig explained.
Disclosure: For full disclosures of the study authors, visit ash.confex.com.
