Aptevo Reports 21% of Evaluable Frontline AML Patients Reached Stem Cell Transplant
Aptevo Therapeutics reported that ten of 47 evaluable patients with newly diagnosed AML advanced to allogeneic stem cell transplant after receiving mipletamig with venetoclax and azacitidine.
Aptevo Therapeutics Inc. (Nasdaq:APVO) reported that ten patients with newly diagnosed acute myeloid leukemia (AML) proceeded to allogeneic stem cell transplant after treatment with mipletamig alongside venetoclax and azacitidine. The patients had initially been considered unsuitable for intensive induction chemotherapy.
Ten of 47 evaluable frontline patients, or 21%, reached allogeneic stem cell transplantation. Nine patients were enrolled in the ongoing Phase 1b RAINIER trial, while one came from an earlier dose expansion trial.
Allogeneic transplant uses donor cells to replace a patient's blood-forming stem cells. Aptevo said the procedure can provide eligible patients with the possibility of long-term remission or cure. Reaching transplant depends on an adequate response to initial treatment, medical eligibility, a suitable donor and an appropriate treatment plan.
The patient group had initially been deemed unfit for intensive chemotherapy. Aptevo said advanced age, existing health conditions and other factors can restrict treatment options in this population.
Aptevo compared the result with data from the Phase 3 VIALE-A trial. In that study, three of 286 patients, or 0.7%, who received venetoclax and azacitidine subsequently underwent stem cell transplantation.
The company cautioned that comparisons between trials are limited because of differences in patient populations, study design and follow-up. Aptevo said the observations contribute to its clinical assessment of mipletamig in combination with venetoclax and azacitidine.
RAINIER is Aptevo's Phase 1b/2 study of mipletamig with venetoclax and azacitidine in newly diagnosed AML patients who are not eligible for intensive induction chemotherapy. The current stage is assessing mipletamig dosing to inform the next stage of clinical testing.
Aptevo expects to complete the dose optimisation work by year-end 2026. The company also expects to discuss next steps with regulators in the first half of 2027, with FDA interaction and initiation of a Phase 2 clinical trial anticipated in the first half of 2027.
These statements are forward-looking expectations from Aptevo. The company said future results could be affected by further assessment of preliminary or interim data, different findings in later clinical trials, adverse events, unexpected safety issues, developments in clinical testing and changes in regulatory, social, macroeconomic and political conditions.
Dirk Huebner, M.D., Aptevo's Chief Medical Officer, said the transplant analysis adds to the company's assessment of mipletamig in frontline AML and supports continued evaluation of the three-drug combination. He also referred to earlier TP53 findings, which Aptevo had described as encouraging given the historically poor outcomes associated with that mutation.
Aptevo describes mipletamig as a drug candidate designed to direct the immune system against leukemic cells and leukemic stem cells expressing CD123. The company says the treatment is designed to bring leukemic cells and T cells into close proximity to trigger the destruction of leukemic cells.
Aptevo is a clinical-stage biotechnology company developing bispecific and trispecific immunotherapies for cancer. Its pipeline candidates use the ADAPTIR™ and ADAPTIR-FLEX™ platforms, while mipletamig is its lead clinical candidate in AML.
Aptevo reported that ten of 47 evaluable frontline AML patients, or 21%, proceeded to allogeneic stem cell transplant after treatment with mipletamig, venetoclax and azacitidine.
Nine patients came from the ongoing Phase 1b RAINIER trial and one from a completed dose expansion trial.
The patients had initially been considered unfit for intensive induction chemotherapy.
Aptevo cited three of 286 patients, or 0.7%, undergoing transplant in the VIALE-A VEN+AZA trial, while noting that cross-trial comparisons are limited.
The company expects to complete RAINIER dose optimisation by year-end 2026 and anticipates FDA interaction and Phase 2 trial initiation in the first half of 2027.
Aptevo Therapeutics Inc. announced that ten patients with newly diagnosed acute myeloid leukaemia (AML) advanced to allogeneic stem cell transplant after treatment with mipletamig combined with venetoclax and azacitidine. The patients were initially considered unfit for intensive induction chemotherapy.
Aptevo Therapeutics Inc. made the announcement on October 26, 2026.
Ten of 47 evaluable frontline patients, or 21%, proceeded to allogeneic stem cell transplantation. Nine patients came from the ongoing Phase 1b RAINIER trial and one came from a previously completed dose expansion trial.
The patients received mipletamig in combination with venetoclax and azacitidine, referred to by Aptevo Therapeutics Inc. as VEN+AZA in combination with mipletamig.
Aptevo Therapeutics Inc. said stem cell transplant can offer eligible patients the possibility of long-term remission or cure. The company also said that reaching transplant requires an adequate response to initial treatment, medical eligibility, and a suitable donor and treatment plan.
Aptevo Therapeutics Inc. cited the Phase 3 VIALE-A trial, in which three of 286 patients, or 0.7%, receiving VEN+AZA subsequently underwent stem cell transplantation, compared with 21% in the company's analysis. Aptevo cautioned that cross-trial comparisons are limited by differences in patient populations, study design and follow-up.
The analysis concerned newly diagnosed AML patients who were initially deemed unfit for intensive induction chemotherapy. Aptevo Therapeutics Inc. said advanced age, underlying health conditions and other factors can limit treatment options for this population.
Dirk Huebner, M.D., Aptevo Therapeutics Inc.'s Chief Medical Officer, said the transplant observations add another dimension to the clinical activity reported for mipletamig and support continued evaluation of the mipletamig triplet. He also referred to previously reported TP53 findings as encouraging in light of the historically poor outcomes associated with that mutation.
Aptevo Therapeutics Inc. is evaluating mipletamig with venetoclax and azacitidine in RAINIER, its Phase 1b/2 study in newly diagnosed AML patients who are not eligible for intensive induction chemotherapy. The current stage is evaluating mipletamig dosing to guide the next stage of clinical testing.
Aptevo Therapeutics Inc. expects to complete the current RAINIER dose-optimisation work by year-end 2026 and discuss next steps with regulators in the first half of 2027. The company also said FDA interaction and initiation of a Phase 2 clinical trial are anticipated in the first half of 2027.
Aptevo Therapeutics Inc. says mipletamig is designed to redirect the patient's immune system to destroy leukemic cells and leukemic stem cells expressing CD123. It is designed to engage leukemic cells and T cells and bring them closely together to trigger destruction of leukemic cells.
Aptevo Therapeutics Inc. is identified in the announcement as listed on Nasdaq under the ticker symbol APVO.
Aptevo Therapeutics Inc. is a clinical-stage biotechnology company focused on developing novel bispecific and trispecific immunotherapies for cancer. Its lead clinical candidate is mipletamig, and the company also develops pipeline candidates using its ADAPTIR™ and ADAPTIR-FLEX™ platforms.
Aptevo Therapeutics Inc. said its forward-looking statements may be affected by further assessment of preliminary or interim data, different results from later clinical trials, adverse events, unexpected safety issues, adverse developments in clinical development, and changes in regulatory, social, macroeconomic and political conditions. The company said it cannot guarantee that any forward-looking statement will be accurate and cautioned investors not to place undue reliance on them.