Clinical Trial Details
— Status: Completed
Administrative data
NCT number |
NCT04173585 |
Other study ID # |
NCT-2017-0530 |
Secondary ID |
|
Status |
Completed |
Phase |
Phase 2
|
First received |
|
Last updated |
|
Start date |
October 22, 2019 |
Est. completion date |
March 24, 2023 |
Study information
Verified date |
March 2023 |
Source |
University Hospital Heidelberg |
Contact |
n/a |
Is FDA regulated |
No |
Health authority |
|
Study type |
Interventional
|
Clinical Trial Summary
The long-term outcome of patients with acute myeloid leukemia (AML) remains poor, with less
than 30% of patients achieving long lasting remission or cure. This poor outcome is largely
due to refractoriness to induction chemotherapy as well as relapses during and after
completion of intensive induction and consolidation therapy. In patients with
refractory/relapsed AML hematopoietic cell transplantation (allo-HCT) is currently the only
treatment option offering a prospect of cure but outcome is heavy influenced by the remission
status before allo-HCT. Therefore, patients are typically treated with salvage regimens based
on high dose cytarabine (HiDAC) combined with mitoxantrone, fludarabine or idarubicin.
Nevertheless, the remission rates remain poor and currently there is no accepted standard
salvage regimen. Recent studies indicate that combination chemotherapy including HiDAC and
gemtuzumab ozogamicin (GO) at a dose of 3 mg/m² leads to improved response rates in
refractory AML.
Proteasome inhibition with bortezomib appears to be a promising treatment strategy to restore
chemo-sensitivity via EZH2 stabilisation.
This study aims at improving response rates in refractory/ relapsed AML by combining high
dose cytarabine, gemtuzumab ozogamicin (GA) and bortezomib (B).
During this phase II study efficacy of B-GA is assessed in comparison to matched historical
controls using the Matched Threshold Crossing (MTC)-approach. If results are promising, a
subsequent randomized phase III study is intended to assess the efficacy of GA with or
without bortezomib.
Description:
Acute Myeloid Leukemia (AML) is a clonal malignant disorder which is characterized by the
expansion of leukemic blasts in the bone marrow and the peripheral blood, which goes along
with a suppression of normal hematopoiesis including granulopoiesis, erythropoiesis and
thrombocytopoiesis. The prognosis is largely determined by cytogenetic and molecular risk
factors, age, performance status and antecedent Myelodysplastic Syndrome (MDS).
With the exception of old and frail patients, most AML patients are eligible for intensive
chemotherapy, which is given in curative intent consisting of induction and consolidation
therapy. However, despite intensive therapy, the long-term outcome of AML patients remains
poor, with less than 30% of patients achieving long lasting remission and even cure. This
poor outcome is largely due to refractoriness to induction chemotherapy as well as relapses
during and after completion of intensive induction and consolidation therapy. Regarding
refractoriness, about 20-30% of AML patients under the age of 60 years and about 50% of older
patients fail to attain complete remission (CR) following cytarabine plus anthracycline based
standard induction therapy. Regarding relapses, even patients having achieved complete
remission are at a high risk of relapse, particularly within the first two years after
completion of chemotherapy.
In patients with blast persistence after induction therapy or relapse, allogeneic
hematopoietic cell transplantation (allo-HCT) is currently the only treatment strategy to
offer the prospect of cure. Outcome of allo-HCT is heavily influenced by the remission state
before allo-HCT. With the aim to induce a complete remission (CR) before allo-HCT, salvage
chemotherapy regimens are administered in refractory/relapsed patients. Typically, these
salvage regimens are based on high dose cytarabine (HiDAC), which is frequently combined with
either mitoxantrone (HAM regimen) or fludarabine plus idarubicin (idaFLA regimen). Currently,
there is no commonly accepted standard salvage regime, but a large individual patient data
meta-analysis and single arm phase-II studies suggest that combination chemotherapy including
HiDAC and gemtuzumab ozogamicin, an antibody drug conjugate, are very effective. Since
patients with refractory or relapsed AML are candidates for allo-HCT, the main purpose of the
salvage regimen is to bridge patients to allo-HCT with induction of a CR before allo-HCT.
Therapy resistance in cancer is still poorly understood. Beyond genetic aberrations
epigenetic mechanisms are important components of resistance to cancer therapy. Recently, the
investigators discovered an epigenetic therapy resistance mechanism in AML (Figure 1). This
mechanism might be relevant in up to 50% of relapsed/refractory AML patients. This epigenetic
mediated resistance can be successfully overcome in in vitro models by proteasome inhibition.
Currently, relapsed and refractory r/r-AML still carries a dismal prognosis. In this
multicentre, phase II trial the investigators will analyze efficacy of a novel therapy
regimen for r/r-AML.
As detailed above, combination-chemotherapy including GO and HiDAC based chemotherapy is an
effective regimen in r/r-AML.
Proteasome inhibitors can restore EZH2 protein levels in vitro and in vivo. The restoration
of EZH2 significantly improved efficacy of anti-leukemic therapy. Based on the data mentioned
above we combine the treatment efficacy of GO plus cytarabine based chemotherapy with the
proteasome inhibitor bortezomib in the B-GA regimen. With such an approach the investigators
believe that they can substantially improve treatment results in r/r-AML. Part of the study
is a pre-specified biomarker analysis for EZH2 restoration after bortezomib exposure in vitro
and in vivo. Accordingly, we will be able to determine whether EZH2 restoration after
bortezomib exposure is associated with response and outcome. There have been rare reports of
acute diffuse infiltrative pulmonary disease of unknown etiology such as pneumonitis,
interstitial pneumonia, lung infiltration and Acute Respiratory Distress Syndrome (ARDS) in
patients receiving bortezomib. In particular, 2 patients with r/r-AML given high-dose
cytarabine (2 g/m²/day) by continuous infusion in combination with daunorubicin and
bortezomib died of ARDS early in the course of therapy. However, in several trials evaluating
the combination of bortezomib with standard and high-dose cytarabine in AML patients no
toxicity signal was detected, especially with respect to ARDS.
Taken together, the rationale for this trial is based on the high unmet clinical need and
strong in vitro evidence.