If your child has pediatric acute myeloid leukemia (AML), you may be eligible to participate in this study and receive an investigational therapy designed specifically for their condition.

FRα is a protein that is very common in leukemia cell membranes

To qualify for REFRɑME-P1, patients must meet the following criteria:

• Diagnosis of CBFA2T3::GLIS2 positive AML that is either refractory (not responding to prior AML treatments) or relapsed (initially responsive but then recurring).
• Presence of at least 5% leukemia blasts in the bone marrow, as determined by standard microscopy.
• Age under 12 years.

All participants will initially receive luveltamab tazevibulin as the sole AML treatment. The first 6 to 12 subjects will be randomly assigned to receive either 3.5 mg/kg or 4.3 mg/kg of luveltamab tazevibulin every 2 weeks to identify the optimal dose based on safety, efficacy, and pharmacokinetics. Subsequent participants will receive the selected dose (either 3.5 mg/kg or 4.3 mg/kg) every 2 weeks.

Responders: Children who respond to the treatment after two cycles (4 doses) will continue with luveltamab tazevibulin monotherapy for up to two years, or until relapse, unmanageable adverse events, or withdrawal. Responding patients may also undergo HSCT at the discretion of the principal investigators. 

Non-responders: Children who do not respond after two cycles may receive a higher dose of luveltamab tazevibulin. If this still does not yield a response or is poorly tolerated, the treating physician may either discontinue the study treatment or combine luveltamab tazevibulin (4.3 mg/kg every 4 weeks) with one of the standard AML treatments outlined in the protocol.

Before starting the study, a potential participant will undergo a screening period lasting about three weeks. Parents or guardians will receive detailed information about the screening and treatment process, including potential risks.

The first two cycles of treatment will involve frequent visits for blood draws and physical exams. Afterward, visits will be less frequent, limited to the days of treatment every 2 or 4 weeks. Bone marrow biopsies, aspirates, and lumbar punctures will be performed every cycle (4 weeks) until Cycle 3, then approximately every two cycles.

Luveltamab tazevibulin is an innovative drug targeting the FRɑ protein, which is present on most CBFA2T3::GLIS2 cells but not on normal blood cells. This targeted approach is currently the only strategy aimed at specifically treating CBFA2T3::GLIS2 AML. Sutro has previously provided luveltamab tazevibulin through Compassionate Use Access, with initial results from 25 children presented by the treating physiciansat the 2023 American Society of Hematology meeting (https://ash.confex.com/ash/2023/webprogram/Paper180141.html). While these results are promising, the treatment remains experimental.

If you are interested in this study for your child, please discuss it with their Pediatric Hematologist Oncologist. If the study is not available at your child’s current treatment institution, their physician may contact a participating institution to explore potential transfer of care.

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