Modified LCH-III Regimen With or Without Luvometinib for Multisystem Pediatric Langerhans Cell Histiocytosis

Официальное название

Modified LCH-III Regimen Versus Modified LCH-III Regimen Combined With Luvometinib in the Treatment of Multisystem Pediatric Langerhans Cell Histiocytosis: A Multicenter, Open-Label, Randomized Controlled Clinical Trial

Обзор

Langerhans cell histiocytosis (LCH) is the most common histiocytic disorder in children, caused by excessive proliferation and accumulation of Langerhans cells (a type of immune cell) in various body tissues. The annual incidence is about 2.6-8.9 cases per million children.Clinical presentation varies widely. Mild (low-risk) cases may resolve spontaneously or cause minimal issues with excellent outcomes. Severe multisystem LCH involves multiple organs, particularly high-risk sites such as liver, spleen, or bone marrow, leading to poorer prognosis and potential life-threatening complications without appropriate treatment.Standard first-line therapy for many children is prednisone (a corticosteroid) plus vinblastine (chemotherapy). Trials like LCH-III show near-100% survival in low-risk disease, but long-term survival drops to \~80% in high-risk cases. Reactivation occurs in \~37% of low-risk patients post-treatment, and \~50% of children eventually develop resistance, resulting in progression or relapse. Treatment failure heightens risks of long-term sequelae, including growth retardation, endocrine dysfunction, and neurological damage, severely impacting quality of life. More than half of LCH cases harbor the BRAF V600E mutation, activating the MAPK pathway abnormally. This has driven development of targeted MAPK inhibitors (e.g., vemurafenib, dabrafenib, trametinib), which demonstrate strong efficacy and acceptable safety (mainly manageable skin rash) in relapsed/refractory pediatric cases, with no reported secondary malignancies to date. These agents provide rapid symptom relief and durable control, though monotherapy often fails to eradicate abnormal cells in multisystem disease, leading to relapse after discontinuation. No MAPK inhibitors were previously approved specifically for LCH. In 2025, luvometinib (developed by Fosun Pharma, China; a selective MEK1/2 inhibitor) received approval in China for adult LCH and histiocytic neoplasms. Adult studies showed \~83% objective response rate and \~74% progression-free at ≥12 months, with mostly mild side effects (skin issues, hypertriglyceridemia) and no discontinuations due to serious toxicity. Laboratory evidence indicates MAPK overactivation confers apoptosis resistance to LCH cells; combining MAPK inhibitors with chemotherapy may enhance cell killing and leverage chemotherapy-induced immune microenvironment changes for better clearance. Small studies and real-world data in refractory LCH support this: combination regimens yielded low relapse rates (especially with prolonged therapy), 100% responses in some pediatric cohorts with sustained remission and no added severe toxicity, and notably lower relapse (20% vs 75% with inhibitor alone) in our center's early experience with LCH-III backbone plus MAPK inhibitor. This multicenter randomized trial will enroll children with multisystem LCH, assigning them to modified standard LCH-III chemotherapy alone or the same regimen combined with luvometinib, to evaluate whether adding this targeted agent improves outcomes.

Подробное описание

Lab studies show that when the MAPK pathway is overactive, it makes LCH cells harder to kill (more resistant to dying naturally). Combining an MAPK inhibitor with chemotherapy might make the abnormal cells easier to destroy. Chemotherapy also changes the immune environment in the body, which could help clear out the bad cells more completely.

Several small studies and real-world experiences have already tested this idea in children and adults with hard-to-treat LCH:

One study combined MAPK inhibitors with certain chemotherapy drugs and saw very few relapses, especially when treatment lasted longer.

Another study using a similar approach achieved 100% response in a group of children (including some as first treatment), with most staying in remission afterward, and no extra serious side effects from the combination.

A Chinese study using prednisone, another chemo drug, plus an MAPK inhibitor showed good results with low relapse after stopping.

Early data from our own center found that children who got an MAPK inhibitor together with the standard LCH-III treatment had much lower relapse rates (only 20%) compared to those who got the inhibitor alone (75% relapse).

Based on this growing evidence, this study plans to run a large, carefully designed trial at multiple hospitals. It will randomly assign children with multisystem LCH to receive either the improved (modified) version of the standard LCH-III chemotherapy alone, or the same chemotherapy combined with luvometinib. The goal is to compare how well each approach works and to learn more about whether adding this targeted drug to chemotherapy can improve treatment for children with this disease.

Вмешательства

• Препарат Prednisone
  Corticosteroid administered orally as part of the modified LCH-III regimen
• Препарат Vincristine
  Intravenous vinca alkaloid chemotherapy agent used in the modified LCH-III regimen
• Препарат Mercaptopurine
  Oral purine analog antimetabolite used in the maintenance phase of therapy for multisystem LCH
• Препарат Luvometinib
  Oral selective MEK1/2 inhibitor added to the experimental arm. Administered daily in combination with modified LCH-III chemotherapy for multisystem Langerhans cell histiocytosis.

Первичные конечные точки

• Event-Free survival rate [Срок оценки: From Day 1 until the date of first event or last follow-up, assessed up to 2 years.]

Вторичные конечные точки (3)

• Objective response rate [Срок оценки: At 1 month and 3 months post-treatment]
• Overall survival rate [Срок оценки: From Day1 until date of death from any cause or last follow-up, assessed up to 2 years.]
• Number of participants with treatment-related adverse events as assessed by CTCAE v5.0 [Срок оценки: From Day 1 until through study completion, an average of 2 years]

Критерии участия

Критерии включения

• Children aged 0-18 years, of either sex.
• Pathologically confirmed diagnosis of Langerhans cell histiocytosis (LCH) with positive staining for CD1a and/or CD207 (Langerin), and no prior treatment specifically directed against LCH.
• Multisystem involvement of LCH, as determined by clinical and imaging evaluation.
• Provision of written informed consent (by parent/legal guardian and, where appropriate, assent from the child), with willingness to comply with the study treatment regimen and follow-up assessments.

Критерии исключения

• Presence of any other significant underlying medical condition, including but not limited to primary immunodeficiency disorders, congestive heart failure, renal insufficiency, chronic viral hepatitis, HIV infection, or status post solid organ transplantation.
• History of a second (secondary) malignancy.
• QTcF interval > 0.47 seconds on electrocardiogram performed prior to enrollment.
• Ophthalmologic screening prior to enrollment revealing retinal vein occlusion, retinal pigment epithelial detachment, or other clinically significant ocular abnormalities that, in the opinion of the investigator, contraindicate participation.
• LCH harboring Class 3 MEK pathway mutations, specifically the following alterations: L98\_I103del, L98\_K104del, P105\_A106del, P105\_I107delinsL, L101\_I103delinsF, E102\_I103delinsF, E102\_I103del, E102\_I103delinsV, E102\_I103delinsVN, E102\_K104delinsQ, or I103\_A106del.
• Refusal or inability to provide written informed consent (or assent, as applicable).

Критерии приведены из реестра в оригинале (на английском). Окончательную оценку соответствия проводит исследовательский центр.

Здоровые добровольцы: Нет

Дизайн исследования

Распределение

Рандомизированное

Модель

Параллельные группы

Маскирование

Открытое

Основная цель

Лечение

Центры проведения

Китай · 11 центров

• West China Second Hospital, Sichuan University — Чэнду
• Affiliated Hospital of Guizhou Medical University — Guiyang
• Anhui Provincial Children's Hospital — Хэфэй
• The Second Affiliated Hospital of Anhui Medical University — Хэфэй
• Jiangxi Provincial Children's Hospital — Jiangxi
• Kunming Children's Hospital — Куньмин
• The Second Affiliated Hospital of Guangxi Medical University — Nanning
• The First Affiliated Hospital of Xinjiang Medical University — Ürümqi
• … и ещё 3 центра

Публикации

• Lei J, Wang W, Lin D, Zhu C, Jia W, Weng W, Liu X, Ma Y, Wang Z, Yang L, He X, He Y, Li Y. Vemurafenib combined with chemotherapy achieved sustained remission in pediatric LCH: a multi-center observational study. J Cancer Res Clin Oncol. 2024 Jan 17;150(1):12. doi: 10.1007/s00432-023-05551-y. PMID 38231288
• Evseev D, Osipova D, Kalinina I, Raykina E, Ignatova A, Lyudovskikh E, Baidildina D, Popov A, Zhogov V, Semchenkova A, Litvin E, Kotskaya N, Cherniak E, Voronin K, Burtsev E, Bronin G, Vlasova I, Purbueva B, Fink O, Pristanskova E, Dzhukaeva I, Erega E, Novichkova G, Maschan A, Maschan M. Vemurafenib combined with cladribine and cytarabine results in durable remission of pediatric BRAF V600E-posit PMID 37216396
• Karri V, Lin H, Velazquez J, Batajoo A, Parekh D, Stanton W, Abhyankar H, El-Mallawany NK, Agrusa J, Eckstein O, Gulati N, Schwartz J, Woods-Swafford W, Boyd J, Saha A, Allen CE, McClain KL. Clinical, radiological and molecular responses to combination chemotherapy with MAPK pathway inhibition in relapsed and refractory Langerhans cell histiocytosis. Br J Haematol. 2024 May;204(5):1882-1887. doi: PMID 38501390
• Bigenwald C, Le Berichel J, Wilk CM, Chakraborty R, Chen ST, Tabachnikova A, Mancusi R, Abhyankar H, Casanova-Acebes M, Laface I, Akturk G, Jobson J, Karoulia Z, Martin JC, Grout J, Rafiei A, Lin H, Manz MG, Baccarini A, Poulikakos PI, Brown BD, Gnjatic S, Lujambio A, McClain KL, Picarsic J, Allen CE, Merad M. BRAFV600E-induced senescence drives Langerhans cell histiocytosis pathophysiology. Nat M PMID 33958797
• Hogstad B, Berres ML, Chakraborty R, Tang J, Bigenwald C, Serasinghe M, Lim KPH, Lin H, Man TK, Remark R, Baxter S, Kana V, Jordan S, Karoulia Z, Kwan WH, Leboeuf M, Brandt E, Salmon H, McClain K, Poulikakos P, Chipuk J, Mulder WJM, Allen CE, Merad M. RAF/MEK/extracellular signal-related kinase pathway suppresses dendritic cell migration and traps dendritic cells in Langerhans cell histiocytosis l PMID 29263218
• Cao XX, Zhu Q, Cai Z, Ma J, Zhou H, Chang L, Zhong LP, Wu ZL, Wang X, Han P, Lin HM, Wei Z, Guo JY, Zheng Y, Li J. Luvometinib in patients with Langerhans cell histiocytosis, Erdheim-Chester disease, and other histiocytic neoplasms: a single-arm, multicentre, phase 2 study. EClinicalMedicine. 2025 Sep 17;88:103486. doi: 10.1016/j.eclinm.2025.103486. eCollection 2025 Oct. PMID 41035796
• Keam SJ. Luvometinib: First Approval. Drugs. 2025 Sep;85(9):1177-1183. doi: 10.1007/s40265-025-02217-6. Epub 2025 Aug 2. PMID 40751881
• Whitlock JA, Geoerger B, Dunkel IJ, Roughton M, Choi J, Osterloh L, Russo M, Hargrave D. Dabrafenib, alone or in combination with trametinib, in BRAF V600-mutated pediatric Langerhans cell histiocytosis. Blood Adv. 2023 Aug 8;7(15):3806-3815. doi: 10.1182/bloodadvances.2022008414. PMID 36884302

Идентификаторы

NCT: NCT07431060 · WCSH-NCP-MS-LCH-2026

Первоисточники (государственные реестры)

• ClinicalTrials.gov (NIH, США)

Открыть это исследование на ClinicalTrials.gov ↗