AML: Shorter Venetoclax Course Shows Promise for Some

CHICAGO — An abbreviated course of azacitidine for 7 days plus venetoclax for 7 days showed similar efficacy to a standard hypomethylating agent plus venetoclax doublets in older and unfit patients with newly diagnosed acute myeloid leukemia (AML) in a multicenter retrospective analysis.

However, the azacitidine plus venetoclax therapy — the “7+7” regimen — was associated with lower platelet transfusion requirements and lower 8-week mortality, suggesting the regimen might be preferable in certain patient populations, Alexandre Bazinet, MD, of the University of Texas MD Anderson Cancer Center, Houston, reported at the American Society of Clinical Oncology (ASCO) annual meeting.

The composite complete remission (CRc) rate, including complete remission with or without complete count recovery, was identical at 72% among 82 patients treated with the 7+7 regimen and 166 treated with standard therapy, and the complete remission (CR) rate was 57% and 55%, respectively, Dr. Bazinet said.

The median number of cycles to first response was one in both groups, but 42% of responders in the 7+7 group required more than one cycle to achieve their first response, compared with just 1% of those in the standard therapy group, he noted, adding that the median number of cycles to achieve best response was two in the 7+7 group and one in the standard therapy group.

The mortality rate at 4 weeks was similar in the groups (2% vs 5% for 7+7 vs standard therapy), but at 8 weeks, the mortality rate was significantly higher in the standard therapy group (6% vs 16%, respectively). Median overall survival (OS) was 11.2 months versus 10.3 months, and median 2-year survival was 27.7% versus 33.6% in the groups, respectively.

Event-free survival was 6.5 versus 7.4 months, and 2-year event-free survival was 24.5% versus 27.0%, respectively.

Of note, fewer patients in the 7+7 group required platelet transfusions during cycle 1 (62% vs 77%) and the cycle 1 rates of neutropenic fever and red cell transfusion requirements were similar in the two treatment groups, Dr. Bazinet said.

Study participants were 82 adults from seven centers in France who received the 7+7 regimen, and 166 adults from MD Anderson who received standard therapy with a hypomethylating agent plus venetoclax doublets given for 21-28 days during induction. Preliminary data on the 7+7 regimen in patients from the French centers were reported previously and “suggested preserved efficacy with potentially less toxicity,” he noted.

“A hypomethylating agent plus venetoclax doublets are standard-of-care in patients with AML who are older or ineligible for chemotherapy due to comorbidities,” Dr. Bazinet explained, adding that although the venetoclax label calls for 28 days of drug per cycle, shorter courses of 14 to 21 days are commonly used.

These findings are limited by the retrospective study design and by small patient numbers in many subgroups, he said.

“In addition, the cohorts were heterogeneous, consisting of patients treated with a variety of different regimens and across multiple centers and countries. The distribution of FLT3-ITD and NRAS/KRAS mutations differed significantly between cohorts,” he explained, also noting that prophylactic azole use differed across the cohort. “Furthermore, analysis of the toxicity results was also limited by likely differing transfusion polices in different centers.”

Overall, however, the findings suggest that reducing the duration of venetoclax is safe and results in similar CRc rates, although responses may be faster with standard dosing, he said, adding that “7+7 is potentially less toxic and is attractive in patients who are more frail or at risk for complications.”

“Our data support further study of shorter venetoclax duration, within emerging triplet regimens in patients with intermediate or low predictive benefit to mitigate toxicity,” he concluded.

Dr. Bazinet reported having no disclosures.

CHICAGO — An abbreviated course of azacitidine for 7 days plus venetoclax for 7 days showed similar efficacy to a standard hypomethylating agent plus venetoclax doublets in older and unfit patients with newly diagnosed acute myeloid leukemia (AML) in a multicenter retrospective analysis.

However, the azacitidine plus venetoclax therapy — the “7+7” regimen — was associated with lower platelet transfusion requirements and lower 8-week mortality, suggesting the regimen might be preferable in certain patient populations, Alexandre Bazinet, MD, of the University of Texas MD Anderson Cancer Center, Houston, reported at the American Society of Clinical Oncology (ASCO) annual meeting.

The composite complete remission (CRc) rate, including complete remission with or without complete count recovery, was identical at 72% among 82 patients treated with the 7+7 regimen and 166 treated with standard therapy, and the complete remission (CR) rate was 57% and 55%, respectively, Dr. Bazinet said.

The median number of cycles to first response was one in both groups, but 42% of responders in the 7+7 group required more than one cycle to achieve their first response, compared with just 1% of those in the standard therapy group, he noted, adding that the median number of cycles to achieve best response was two in the 7+7 group and one in the standard therapy group.

The mortality rate at 4 weeks was similar in the groups (2% vs 5% for 7+7 vs standard therapy), but at 8 weeks, the mortality rate was significantly higher in the standard therapy group (6% vs 16%, respectively). Median overall survival (OS) was 11.2 months versus 10.3 months, and median 2-year survival was 27.7% versus 33.6% in the groups, respectively.

Event-free survival was 6.5 versus 7.4 months, and 2-year event-free survival was 24.5% versus 27.0%, respectively.

Of note, fewer patients in the 7+7 group required platelet transfusions during cycle 1 (62% vs 77%) and the cycle 1 rates of neutropenic fever and red cell transfusion requirements were similar in the two treatment groups, Dr. Bazinet said.

Study participants were 82 adults from seven centers in France who received the 7+7 regimen, and 166 adults from MD Anderson who received standard therapy with a hypomethylating agent plus venetoclax doublets given for 21-28 days during induction. Preliminary data on the 7+7 regimen in patients from the French centers were reported previously and “suggested preserved efficacy with potentially less toxicity,” he noted.

“A hypomethylating agent plus venetoclax doublets are standard-of-care in patients with AML who are older or ineligible for chemotherapy due to comorbidities,” Dr. Bazinet explained, adding that although the venetoclax label calls for 28 days of drug per cycle, shorter courses of 14 to 21 days are commonly used.

These findings are limited by the retrospective study design and by small patient numbers in many subgroups, he said.

“In addition, the cohorts were heterogeneous, consisting of patients treated with a variety of different regimens and across multiple centers and countries. The distribution of FLT3-ITD and NRAS/KRAS mutations differed significantly between cohorts,” he explained, also noting that prophylactic azole use differed across the cohort. “Furthermore, analysis of the toxicity results was also limited by likely differing transfusion polices in different centers.”

Overall, however, the findings suggest that reducing the duration of venetoclax is safe and results in similar CRc rates, although responses may be faster with standard dosing, he said, adding that “7+7 is potentially less toxic and is attractive in patients who are more frail or at risk for complications.”

“Our data support further study of shorter venetoclax duration, within emerging triplet regimens in patients with intermediate or low predictive benefit to mitigate toxicity,” he concluded.

Dr. Bazinet reported having no disclosures.

CHICAGO — An abbreviated course of azacitidine for 7 days plus venetoclax for 7 days showed similar efficacy to a standard hypomethylating agent plus venetoclax doublets in older and unfit patients with newly diagnosed acute myeloid leukemia (AML) in a multicenter retrospective analysis.

However, the azacitidine plus venetoclax therapy — the “7+7” regimen — was associated with lower platelet transfusion requirements and lower 8-week mortality, suggesting the regimen might be preferable in certain patient populations, Alexandre Bazinet, MD, of the University of Texas MD Anderson Cancer Center, Houston, reported at the American Society of Clinical Oncology (ASCO) annual meeting.

The composite complete remission (CRc) rate, including complete remission with or without complete count recovery, was identical at 72% among 82 patients treated with the 7+7 regimen and 166 treated with standard therapy, and the complete remission (CR) rate was 57% and 55%, respectively, Dr. Bazinet said.

The median number of cycles to first response was one in both groups, but 42% of responders in the 7+7 group required more than one cycle to achieve their first response, compared with just 1% of those in the standard therapy group, he noted, adding that the median number of cycles to achieve best response was two in the 7+7 group and one in the standard therapy group.

The mortality rate at 4 weeks was similar in the groups (2% vs 5% for 7+7 vs standard therapy), but at 8 weeks, the mortality rate was significantly higher in the standard therapy group (6% vs 16%, respectively). Median overall survival (OS) was 11.2 months versus 10.3 months, and median 2-year survival was 27.7% versus 33.6% in the groups, respectively.

Event-free survival was 6.5 versus 7.4 months, and 2-year event-free survival was 24.5% versus 27.0%, respectively.

Of note, fewer patients in the 7+7 group required platelet transfusions during cycle 1 (62% vs 77%) and the cycle 1 rates of neutropenic fever and red cell transfusion requirements were similar in the two treatment groups, Dr. Bazinet said.

Study participants were 82 adults from seven centers in France who received the 7+7 regimen, and 166 adults from MD Anderson who received standard therapy with a hypomethylating agent plus venetoclax doublets given for 21-28 days during induction. Preliminary data on the 7+7 regimen in patients from the French centers were reported previously and “suggested preserved efficacy with potentially less toxicity,” he noted.

“A hypomethylating agent plus venetoclax doublets are standard-of-care in patients with AML who are older or ineligible for chemotherapy due to comorbidities,” Dr. Bazinet explained, adding that although the venetoclax label calls for 28 days of drug per cycle, shorter courses of 14 to 21 days are commonly used.

These findings are limited by the retrospective study design and by small patient numbers in many subgroups, he said.

“In addition, the cohorts were heterogeneous, consisting of patients treated with a variety of different regimens and across multiple centers and countries. The distribution of FLT3-ITD and NRAS/KRAS mutations differed significantly between cohorts,” he explained, also noting that prophylactic azole use differed across the cohort. “Furthermore, analysis of the toxicity results was also limited by likely differing transfusion polices in different centers.”

Overall, however, the findings suggest that reducing the duration of venetoclax is safe and results in similar CRc rates, although responses may be faster with standard dosing, he said, adding that “7+7 is potentially less toxic and is attractive in patients who are more frail or at risk for complications.”

“Our data support further study of shorter venetoclax duration, within emerging triplet regimens in patients with intermediate or low predictive benefit to mitigate toxicity,” he concluded.

Dr. Bazinet reported having no disclosures.