Single-arm interventional study with ruxolitinib and AIEOP-BFM 2017 Poland or AIEOP-BFM 2017 standard of care chemotherapy in children with acute lymphoblastic leukemia and confirmed activation of JAK/STAT pathway.

Other illness

• Other condition (either pre-existing or related to leukemia biology as present at diagnosis) or circumstances that significantly conflict with the treatment according to the protocol

Other

• ALL classified as a standard or intermediate risk (SR, MR).
• Early high risk (eHR) ALL without genetic lesions within CRLF2, JAK2, EPOR, or CRLF2 expression on leukemic cells.
• Participation in another clinical trial except for ad-on trials within the scope of supportive care approved by the sponsor

• Newly diagnosed ALL treated according to AIEOP-BFM 2017 Poland or AIEOP-BFM 2017 standard of care protocol.
• Confirmed genetic lesion causing activation of JAK-STAT pathway (CRLF2, JAK2, EPOR, or CRLF2 expression on leukemic cells`surface).
• Stratification as early high risk: - no complete remission on day 33 OR - positivity for KMT2A-AFF1 OR - positivity for TCF3-HLF OR o hypodiploidy <45 chromosomes OR - FCM-MRD in bone marrow on day 15 ≥ 10% and not ETV6-RUNX1 positive OR - IKZF1plus and PCR-MRD at TP1 positive or inconclusive and not positive for ETV6-RUNX1, TCF3-PBX1 or KMT2A rearr. other than KMT2A-AFF1 OR - PCR-MRD at TP1 ≥ 5x10-4 OR -age < 1 year and any KMT2A rearrangement