Ivosidenib leads to complete responses in 32% of IDH1-mutated relapsed/refractory AML

CHICAGO – The investigational drug ivosidenib was associated with durable responses, transfusion independence, and a low rate of serious adverse events in patients with IDH1-mutated relapsed/refractory acute myeloid leukemia (AML), based on results of a phase 1 study presented at the annual meeting of the American Society of Clinical Oncology (ASCO).

Daily oral ivosidenib, which inhibits mutant IDH1 the gene that encodes for isocitrate dehydrogenase 1 and is present in 6%-10% of AML patients, was associated with a complete response rate of nearly 32%. In patients who achieved a complete response, median duration of response was 8.2 months and median overall survival was 18.8 months, Daniel A. Pollyea, MD, University of Colorado School of Medicine, Aurora, reported at the meeting.

A wide variety of study participants achieved transfusion independence, even patients who had lesser and no discernable responses, Dr. Pollyea said. “A significant minority of these patients (with lesser or no response) were able to achieve transfusion independence which is obviously a big achievement with respect to quality of life, and suggestive of the mechanism of action here with respect to differentiation.”

The conclusions of this study are “striking,” with response rates and tolerability “very similar” to results seen with the IDH2 inhibitor enasidenib, said Eunice S. Wang, MD, of Roswell Park Comprehensive Cancer Center, Buffalo, N.Y.

Ivosidenib is “likely to become the new standard of care treatment” for IDH1-mutant patients in the relapsed-refractory setting based on the data presented at ASCO, Dr. Wang said in a presentation commenting on the results.

“Given the development of ivosidenib and enasidenib, I think we should all carefully consider whether testing of IDH1 and IDH2 mutational status should also become standard of care in all relapsed and refractory patients, in order to offer them these novel and highly effective as well as well-tolerated targeted therapies,” she said.

Enasidenib was approved by the U.S. Food and Drug Administration (FDA) in 2017 for relapsed or refractory AML with an IDH2 mutation.

Here at ASCO, Dr. Pollyea reported results based on 179 patients with relapsed/refractory IDH1-mutant AML who received 500 mg of ivosidenib daily.

The overall response rate was 41.9% (75 patients), he said. The rate of complete remission (CR) or CR with partial hematologic recovery (CRh) was 31.8% (57 patients), with a median of 2.0 months to CR/CRh and a median duration of CR/CRh of 8.2 months, he said.

Grade 3 or greater leukocytosis was seen in 8% of patients, and grade 3 or greater QT prolongation was seen in 10% of patients, Dr. Pollyea reported.

IHD differentiation syndrome of any grade was seen in 19 patients (10.6%), and about half of those cases (5%) were grade 3 or greater. However, cases were managed with supportive care, and there were no dose reductions, permanent treatment discontinuations, or deaths due to the condition, Dr. Pollyea said.

Moreover, the majority of those patients (10 out of 19) went on to have a response. “Supportive care and continued treatment can allow for patients ultimately to respond who are experiencing differentiation syndrome,” Dr. Pollyea said.

Results of the phase 1 study were published simultaneously in the New England Journal of Medicine.The trial was sponsored by Agios. Dr. Pollyea reported disclosures related to Agios, as well as Abbvie, argenx, Celgene, Celyad, Curis, Pfizer, and Servier.

SOURCE: Pollyea DA, et al. J Clin Oncol36, 2018 (suppl; abstr 7000).

CHICAGO – The investigational drug ivosidenib was associated with durable responses, transfusion independence, and a low rate of serious adverse events in patients with IDH1-mutated relapsed/refractory acute myeloid leukemia (AML), based on results of a phase 1 study presented at the annual meeting of the American Society of Clinical Oncology (ASCO).

Daily oral ivosidenib, which inhibits mutant IDH1 the gene that encodes for isocitrate dehydrogenase 1 and is present in 6%-10% of AML patients, was associated with a complete response rate of nearly 32%. In patients who achieved a complete response, median duration of response was 8.2 months and median overall survival was 18.8 months, Daniel A. Pollyea, MD, University of Colorado School of Medicine, Aurora, reported at the meeting.

A wide variety of study participants achieved transfusion independence, even patients who had lesser and no discernable responses, Dr. Pollyea said. “A significant minority of these patients (with lesser or no response) were able to achieve transfusion independence which is obviously a big achievement with respect to quality of life, and suggestive of the mechanism of action here with respect to differentiation.”

The conclusions of this study are “striking,” with response rates and tolerability “very similar” to results seen with the IDH2 inhibitor enasidenib, said Eunice S. Wang, MD, of Roswell Park Comprehensive Cancer Center, Buffalo, N.Y.

Ivosidenib is “likely to become the new standard of care treatment” for IDH1-mutant patients in the relapsed-refractory setting based on the data presented at ASCO, Dr. Wang said in a presentation commenting on the results.

“Given the development of ivosidenib and enasidenib, I think we should all carefully consider whether testing of IDH1 and IDH2 mutational status should also become standard of care in all relapsed and refractory patients, in order to offer them these novel and highly effective as well as well-tolerated targeted therapies,” she said.

Enasidenib was approved by the U.S. Food and Drug Administration (FDA) in 2017 for relapsed or refractory AML with an IDH2 mutation.

Here at ASCO, Dr. Pollyea reported results based on 179 patients with relapsed/refractory IDH1-mutant AML who received 500 mg of ivosidenib daily.

The overall response rate was 41.9% (75 patients), he said. The rate of complete remission (CR) or CR with partial hematologic recovery (CRh) was 31.8% (57 patients), with a median of 2.0 months to CR/CRh and a median duration of CR/CRh of 8.2 months, he said.

Grade 3 or greater leukocytosis was seen in 8% of patients, and grade 3 or greater QT prolongation was seen in 10% of patients, Dr. Pollyea reported.

IHD differentiation syndrome of any grade was seen in 19 patients (10.6%), and about half of those cases (5%) were grade 3 or greater. However, cases were managed with supportive care, and there were no dose reductions, permanent treatment discontinuations, or deaths due to the condition, Dr. Pollyea said.

Moreover, the majority of those patients (10 out of 19) went on to have a response. “Supportive care and continued treatment can allow for patients ultimately to respond who are experiencing differentiation syndrome,” Dr. Pollyea said.

Results of the phase 1 study were published simultaneously in the New England Journal of Medicine.The trial was sponsored by Agios. Dr. Pollyea reported disclosures related to Agios, as well as Abbvie, argenx, Celgene, Celyad, Curis, Pfizer, and Servier.

SOURCE: Pollyea DA, et al. J Clin Oncol36, 2018 (suppl; abstr 7000).

CHICAGO – The investigational drug ivosidenib was associated with durable responses, transfusion independence, and a low rate of serious adverse events in patients with IDH1-mutated relapsed/refractory acute myeloid leukemia (AML), based on results of a phase 1 study presented at the annual meeting of the American Society of Clinical Oncology (ASCO).

Daily oral ivosidenib, which inhibits mutant IDH1 the gene that encodes for isocitrate dehydrogenase 1 and is present in 6%-10% of AML patients, was associated with a complete response rate of nearly 32%. In patients who achieved a complete response, median duration of response was 8.2 months and median overall survival was 18.8 months, Daniel A. Pollyea, MD, University of Colorado School of Medicine, Aurora, reported at the meeting.

A wide variety of study participants achieved transfusion independence, even patients who had lesser and no discernable responses, Dr. Pollyea said. “A significant minority of these patients (with lesser or no response) were able to achieve transfusion independence which is obviously a big achievement with respect to quality of life, and suggestive of the mechanism of action here with respect to differentiation.”

The conclusions of this study are “striking,” with response rates and tolerability “very similar” to results seen with the IDH2 inhibitor enasidenib, said Eunice S. Wang, MD, of Roswell Park Comprehensive Cancer Center, Buffalo, N.Y.

Ivosidenib is “likely to become the new standard of care treatment” for IDH1-mutant patients in the relapsed-refractory setting based on the data presented at ASCO, Dr. Wang said in a presentation commenting on the results.

“Given the development of ivosidenib and enasidenib, I think we should all carefully consider whether testing of IDH1 and IDH2 mutational status should also become standard of care in all relapsed and refractory patients, in order to offer them these novel and highly effective as well as well-tolerated targeted therapies,” she said.

Enasidenib was approved by the U.S. Food and Drug Administration (FDA) in 2017 for relapsed or refractory AML with an IDH2 mutation.

Here at ASCO, Dr. Pollyea reported results based on 179 patients with relapsed/refractory IDH1-mutant AML who received 500 mg of ivosidenib daily.

The overall response rate was 41.9% (75 patients), he said. The rate of complete remission (CR) or CR with partial hematologic recovery (CRh) was 31.8% (57 patients), with a median of 2.0 months to CR/CRh and a median duration of CR/CRh of 8.2 months, he said.

Grade 3 or greater leukocytosis was seen in 8% of patients, and grade 3 or greater QT prolongation was seen in 10% of patients, Dr. Pollyea reported.

IHD differentiation syndrome of any grade was seen in 19 patients (10.6%), and about half of those cases (5%) were grade 3 or greater. However, cases were managed with supportive care, and there were no dose reductions, permanent treatment discontinuations, or deaths due to the condition, Dr. Pollyea said.

Moreover, the majority of those patients (10 out of 19) went on to have a response. “Supportive care and continued treatment can allow for patients ultimately to respond who are experiencing differentiation syndrome,” Dr. Pollyea said.

Results of the phase 1 study were published simultaneously in the New England Journal of Medicine.The trial was sponsored by Agios. Dr. Pollyea reported disclosures related to Agios, as well as Abbvie, argenx, Celgene, Celyad, Curis, Pfizer, and Servier.

SOURCE: Pollyea DA, et al. J Clin Oncol36, 2018 (suppl; abstr 7000).