ClinicalTrials.gov record NCT05997602

To Evaluate the Efficacy, Safety, and PK Characteristics of FCN-159 in Pediatric Patients With Refractory/Recurrent LCH

Record copied from ClinicalTrials.gov: Oct 10, 2026AI summaries generated: Jul 27, 2026

A Multi-center, Open-label, Single Arm Phase 2 Study to Evaluate the Efficacy, Safety, and Pharmacokinetic Characteristics of FCN-159 in Pediatric Patients With Refractory/Recurrent Langerhans Cell Histiocytosis

StatusRecruitingThe study is currently enrolling participants. Only the study team can say whether a particular person can join.
Study typeInterventionalA study in which researchers assign participants to one or more interventions, such as a drug, procedure, device, behavioural programme or other approach, to measure their effects.
PhasePhase 2A study that tests whether a treatment has the intended effect and continues to check safety, usually in a larger group than phase 1.
Age2 years old and older
SexAll
LocationChina
AI summaryWhat this study is about, in plain languageShow ▾Hide ▴

AI-written from the registry record, not the study's own wording. May contain errors or omissions. Check the registry text on this page and the original record ↗ before acting on it.

This is a Phase 2, single-arm, open-label study testing FCN-159 given orally once daily in children with refractory or recurrent Langerhans cell histiocytosis. About 56 pediatric patients (ages 2–16) are planned; treatment is given in 28‑day cycles and continued until disease progression, intolerable toxicity, withdrawal, death, or other protocol reasons. The study measures tumor response, safety, and how the drug behaves in the body.

What it is studying. The study is testing whether FCN-159 given alone has measurable anti-tumor activity, what side effects occur, and the drug's pharmacokinetic characteristics in pediatric patients with refractory or recurrent LCH.

What the researchers hope to learn. To measure objective response rate by independent review using PET response criteria; to describe safety and treatment-emergent adverse events; to characterize pharmacokinetics of FCN-159; and to collect secondary outcomes such as disease control rate, clinical benefit rate, time to response, progression-free survival, and overall survival.

What this study is about

The study's own summary, as published on ClinicalTrials.gov. Underlined terms have a short explanation.

This is a rare disease, single-arm, open-label,multi-center, non-randomized Phase 2 clinical study to evaluate the efficacy, safety, and pharmacokinetic characteristics of FCN-159 monotherapy in pediatric patients with refractory/recurrent Langerhans cell histiocytosis (LCH).

Interventions being studied

Being studied in this trial does not mean the treatment or procedure is approved or available for this condition.

Drug
  • FCN-159

Eligibility

The criteria exactly as listed on ClinicalTrials.gov. Only the study team can say whether they apply to you.

Inclusion criteria

  • Age 2-16 (inclusive)
  • Patients with histologically confirmed Langerhans cell histiocytosis (LCH) diagnosed by the central laboratory.
  • If sufficient tumor tissue samples and peripheral blood samples are available, central laboratory biomarker testing is required as follows: including but not limited to ERBB3, BRAF, ARAF, HRAS, KRAS, NRAS, MEK (MAP2K1 and MAP2K2), and other MEK upstream genes.If inability to get tissue, the gene testing results from a local laboratory also can be accepted.
  • Patients who have received at least prior first-line systemic treatment, defined as treatment including vinblastine (VBL) and glucocorticoids for at least 2 weeks. VBL can be substituted with vincristine (VCR) or vindesine (VDS). Alternatively, patients may be unable to tolerate chemotherapy due to severe chemotherapy toxicity. Inability to tolerate chemotherapy is defined as one of the following: Severe liver impairment (liver enzyme elevation ≥ 5 × upper limit of normal (ULN) and bilirubin elevation ≥ 1.5 × ULN), severe neurotoxicity related to vinca alkaloids, chemotherapy-related intracranial hypertension, or grade 4 bone marrow depression with severe infection (sepsis, severe pneumonia, etc.) after chemotherapy.
  • Refractory/relapsed LCH is defined as the presence of one of the following:
  • Failure of prior treatment, i.e., no regression in risk organs after at least 2 weeks of systemic treatment, or overall evaluation of AD-progression or AD-mix;
  • Initial response of the disease to first or second-line systemic treatment is NAD or AD-better or AD-stable, followed by disease reactivation after maintenance therapy for more than 3 months. Second-line treatment includes cytarabine and/or cladribine.
  • Persistent mutated gene positive in plasma free DNA testing during prior treatment (confirmed by 2 consecutive tests) or retest positive after treatment discontinuation;
  • Lack of regression in the affected central nervous system (including the pituitary gland) after treatment;
  • Presence of bone marrow involvement and/or hemophagocytic lymphohistiocytosis (HLH);
  • Presence of evaluable lesions based on PET response criteria (PRC).
  • Patients who have to have recovered from all acute toxic effects of prior anti-tumor therapy, and all relevant toxicities must be ≤ grade 1 (except for alopecia and ototoxicity).
  • Expected survival at least ≥ 3 months;
  • Lansky (≤ 15 years old) and Karnofsky (≥ 16 years old) performance status scores should be ≥ 50%, as shown in Appendix 4.
  • Patients or their legal guardians must be able to understand and willingly sign a written informed consent form.
  • For women of childbearing potential, a serum human chorionic gonadotropin (HCG) pregnancy test must be negative within 7 days before starting treatment.
  • For female patients of childbearing potential: Patients should agree to use effective contraception methods during the treatment period and for at least 90 days after the last dose of study treatment, using dual barrier contraception methods such as condoms, oral or injectable contraceptives, intra-uterine contraceptive devices, etc. Male patients should agree to refrain from donating sperm for at least 90 days after the last dose of study treatment.
  • Adequate bone marrow function: Absolute neutrophil count ≥ 1.0×10\^9/L, hemoglobin ≥ 90g/L, and platelets ≥ 75×10\^9/L without the use of blood transfusions, blood products, or granulocyte colony-stimulating factors. Patients with hematocytopenia below these thresholds due to the underlying disease may be considered for inclusion based on the investigator's comprehensive judgment.
  • Adequate hepatic and renal function: Serum total bilirubin ≤ 1.5 × the upper limit of normal (ULN), or ≤ 5× ULN for patients with Gilbert's syndrome or liver involvement; aspartate aminotransferase (AST), alanine aminotransferase (ALT), and alkaline phosphatase (AKP) ≤ 2.5 × ULN, or ≤ 10 × ULN for patients with liver involvement; albumin ≥ 3g/dL; and creatinine clearance or isotopic glomerular filtration rate (GFR) ≥ 50ml/min/1.73㎡or serum creatinine based on age; hepatic and renal impairment caused by the primary disease may be considered for inclusion based on the investigator's comprehensive judgment.
  • Coagulation: International normalized ratio (INR) and activated partial thromboplastin time (APTT) ≤ 1.5 ULN.

Exclusion criteria

  • Patients who have received any of the following prior treatments:
  • Chemotherapy, targeted therapy, immunotherapy, biologic therapy, or herbal anti-tumor therapy for LCH within 4 weeks or < 5 half-lives (whichever is shorter)before the start of the study drug .
  • Strong CYP3A4, CYP2C8, and CYP2C9 inhibitors or inducers within 14 days before the start of the study drug, except for topical skin application.
  • Gowth factors that promote platelet or white blood cell count or function within 7 days before the start of the study drug.
  • Radiotherapy or major surgical treatment (including craniotomy, thoracotomy, laparotomy, open bone or joint surgery, etc.) within 4 weeks before the start of the study drug.
  • Participated in other interventional clinical trials within 4 weeks before the start of the study drug.
  • MEK 1/2 inhibitors (those who have received this treatment for a short period of ≤ 2 weeks may be included).
  • Anticoagulants within 7 days before the start of the study drug for patients with brain tumors (intracranial masses).
  • Prednisone treatment < 0.5mg/kg/day (or equivalent dose of other corticosteroids) is allowed within one month before enrollment, but must be discontinued 14 days before the start of the study drug. Patients with brain lesions receiving corticosteroid therapy for brain edema must maintain a stable dose for 14 days before enrollment. Hormone replacement therapy is allowed for patients with hypopituitarism due to primary disease involvement of the pituitary.
  • Patients with a history of other malignant tumors or concurrent other malignant tumors (excluding cured non-melanoma skin basal cell carcinoma, ductal carcinoma in situ of the breast, or cervical carcinoma in situ).
  • Uncontrolled hypertension (with medication treatment): Blood pressure (BP) greater than or equal to the 95th percentile for age, height, and sex, as described in Appendix 6.
  • Patients with dysphagia, active gastrointestinal disease, malabsorption syndrome, or other conditions that may affect the absorption of the study drug.
  • Prior or current history of retinal vein obstruction (RVO), retinal pigment epithelial detachment (RPED), glaucoma, and other clinically significant abnormal ophthalmologic examination results.
  • Interstitial pneumonia, including clinically significant radiation pneumonitis. Except for interstitial pneumonia caused by pulmonary involvement of the primary disease.
  • Patients will be excluded if their cardiac function or comorbidities meet any of the following criteria:
  • During the screening period, 12-lead electrocardiogram (ECG) measurements will be taken three times at the study center with a mean value calculated using the QTcF formula provided by the instrument; patients with a mean value of QTcF > 470 milliseconds or with risk factors for QTcF prolongation, such as uncorrected hypokalemia, congenital long QT syndrome, or receiving drugs known to prolong QTcF interval (mainly class Ia, Ic, and III antiarrhythmic drugs) will be excluded from the study. Drugs with the potential to prolong the QTcF interval are listed in Appendix 7.
  • New York Heart Association (NYHA) Class 2 and above congestive heart failure as shown in Appendix 5.
  • Clinically significant arrhythmias, including but not limited to complete left bundle branch block, and second-degree atrioventricular block.
  • Known presence of clinically significant coronary heart disease, cardiomyopathy, or severe valvular disease.
  • Echocardiography examination indicating left ventricular ejection fraction (LVEF) < 50%.
  • Patients with active bacterial, fungal, or viral infections, including active hepatitis B (defined as positive hepatitis B surface antigen and hepatitis B virus DNA > 1000IU/ml or meeting the diagnostic criteria for active hepatitis B infection at the study center) or hepatitis C (positive hepatitis C virus RNA), or human immunodeficiency virus (HIV positive) infection.
  • Patients with known allergies to the study drug, other MEK1/2 inhibitors, or their excipients.
  • Patients with known tumor tissue genetic testing that indicates the presence of MAP2K1 exon 3 deletions (del) or deletion-insertion type (delins/indels) mutations.
  • The investigator considers clinically significant cases that will impede participation in the study or prevent compliance with safety requirements.

Study description and what participation involves

The study's detailed description, as published on ClinicalTrials.gov.

Detailed description from the registry

This is a rare disease, single-arm, open-label,multi-center, non-randomized Phase 2 clinical study to evaluate the efficacy, safety, and pharmacokinetic characteristics of FCN-159 monotherapy in pediatric patients with refractory/recurrent Langerhans cell histiocytosis (LCH). Approximately 56 pediatric patients will be enrolled in this study.The study included screening period, treatment period and follow-up period. Subjects will receive FCN-159 5mg/m² (NMT 8mg, the recommended oral dose for adults), orally, once daily, continuously for 28 days per cycle. Subjects will be treated until disease progression (PD), intolerable toxicity, withdrawal of consent, death, or other protocol-specified reasons. According to the PET Response Criteria and Langerhans Cell Histiocytosis Evaluation and Treatment Guidelines, tumor assessment will be performed until disease progression, death, and withdrawal of information Intention, loss of follow-up, initiation of new antitumor therapy, or study termination.Efficacy evaluation will be performed by the investigator and the Independent Review Committee (IRC), respectively.

AI summaryWhat participation may involve, in plain languageShow ▾Hide ▴

AI-written from the registry record, not the study's own wording. May contain errors or omissions. Check the registry text on this page and the original record ↗ before acting on it.

After screening and any required tumor or blood genetic testing, participants take FCN‑159 by mouth once daily at 5 mg/m² (maximum 8 mg) in continuous 28‑day cycles and continue until disease progression, intolerable toxicity, withdrawal, death, or other protocol reasons. Study procedures include regular tumor assessments using PET Response Criteria and assessments per LCH guidelines, blood tests for safety and for measuring drug levels (pharmacokinetics), and ongoing monitoring for side effects. Efficacy assessments are performed by the investigator and also reviewed by an independent review committee. Follow-up and assessments continue until progression, death, withdrawal of information, loss to follow-up, start of new antitumor therapy, or study termination.

How the study is structured. Phase 2, multi-center, open-label, single-group (no placebo or randomization). Approximately 56 children (ages 2–16) receive oral FCN-159 at 5 mg/m² (not to exceed 8 mg) once daily in continuous 28‑day cycles. Treatment continues until disease progression, intolerable toxicity, withdrawal, death, or other protocol-specified reasons. Tumor response is assessed by investigators and an independent review committee using PET-based criteria and LCH guidelines; safety and blood drug levels are collected over up to 24 months.

Questions you could ask

These questions are suggestions for a conversation with the study team or your own clinician, not advice.

  • The listed sites are in China. Is any of them reachable for me, and does the study help with travel?
  • Which of the eligibility criteria would need to be checked with tests before I could join?

More on Langerhans cell histiocytosis

Important dates

Study start
Sep 28, 2023
Primary completion
May 14, 2025 (estimated)
Study completion
May 14, 2027 (estimated)
Target enrollment
56 participants (estimated)
Last updated on registry
Jan 24, 2025
Data verified
Oct 10, 2026

Sponsor and research team

The lead sponsor funds and oversees the trial. A pharmaceutical or biotech company sponsor typically means the study is testing that company's drug or device; a hospital, university, or government agency usually indicates investigator-initiated or publicly funded research.

Lead sponsor
Shanghai Fosun Pharmaceutical Industrial Development Co. Ltd.

Central study contact

If you're interested in participating, the central contact can answer general questions about the study — including eligibility requirements and how to find a recruiting site near you. Actual eligibility is determined by the site's medical team.

Participating sites (11)

  • Beijing Children's Hospital, Capital Medical UniversityRecruiting

    Beijing, Beijing Municipality · China

    • Rui Zhang
    • Rui Zhang, MD
  • Children's Hospital Affiliated to the Capital Institute of PediatricsNot Yet Recruiting

    Beijing, Beijing Municipality · China

  • Children's Hospital of Chongqing Medical UniversityRecruiting

    Chongqing, Chongqing Municipality · China

  • Sun Yat-Sen Memorial Hpsipital,Sun Yat-Sen UnniversityNot Yet Recruiting

    Guangzhou, Guangdong · China

    • Jianpei Fang, MD
    • Jianpei Fang, MD
  • The First Affiliated Hospital,Sun Yat-sen UniversityNot Yet Recruiting

    Guangzhou, Guangdong · China

  • Shenzhen Children's HospitalNot Yet Recruiting

    Shenzhen, Guangdong · China

  • Henan Children's Hospital Zhengzhou Children's HospitalNot Yet Recruiting

    Zhengzhou, Henan · China

  • Tongji Hospital Affiliated to Tongji Medical College of Huazhong University of Science and TechnologyNot Yet Recruiting

    Wuhan, Hubei · China

  • West China Second University Hospital,Sihuan University/West China women's and Children's HospitalNot Yet Recruiting

    Chengdu, Sichuan · China

  • Children's Hospital, Zhejiang University School of MedicineNot Yet Recruiting

    Hangzhou, Zhejiang · China

Terms used on this page · explanations by MedicalUpdates.ai

single-arm
All participants receive the same treatment or follow the same plan. There is no comparison group within the study.
open-label
No masking is used, so the assigned intervention is not deliberately hidden from participants or study staff.
randomized
Participants are assigned to the study groups by chance, like a coin toss, rather than chosen by the doctor or the participant. This is done so the groups are comparable.
pharmacokinetic
How the body absorbs, distributes, breaks down and removes a drug. It is studied by measuring drug levels or related substances at set times after a dose.
refractory
A condition that has not responded to a treatment. 'Relapsed' means it responded and then came back; 'refractory' means it did not respond in the first place.
histologically confirmed
Removal of a small piece of tissue so it can be examined under a microscope. 'Biopsy-proven' or 'histologically confirmed' means the diagnosis was confirmed by examining tissue under a microscope.
biomarker
Something measurable in the body, such as a blood test result or an imaging finding, that indicates how a condition or treatment is behaving.
glucocorticoids
Steroid medicines, such as prednisone, that reduce inflammation. Studies often require a stable dose at entry or measure whether the study treatment allows the dose to be reduced.
upper limit of normal
The highest value of a blood test that a laboratory considers normal. Criteria such as '≤ 3 × ULN' mean the result must be no more than three times that value.
relapsed
A condition that improved with treatment and has since returned or worsened.
prior treatment
Treatment a person has already had for the condition. A 'line of therapy' is one course of treatment; studies often require, or limit, the number of prior lines.
PET
A scan in which a small amount of a radioactive tracer is injected so that activity in tissues can be seen. Often combined with a CT or MRI scan.
Karnofsky
A scale from 100 (no complaints) down to 0 that describes how well a person can carry out daily activities. Studies often require a minimum score.
performance status
A scale from 0 to 5 that describes how a person's condition affects daily activity. 0 means fully active; 1 means restricted in strenuous activity; 2 means able to self-care but unable to work; higher numbers mean more limitation.
written informed consent
The process of explaining a study, including its risks and what participation involves, so that a person can decide freely whether to take part. Consent is usually documented in writing, and a participant can choose to leave the study later.
women of childbearing potential
Studies often ask participants who could become pregnant, or could father a child, to use contraception during the study and for a period afterwards, because the effect of the treatment on a pregnancy is unknown.
Absolute neutrophil count
The number of neutrophils, a type of white blood cell that fights infection, in a blood sample. Studies often require it to be above a set level.
creatinine clearance
A measure of kidney function, calculated from a blood creatinine level together with age, weight and sex.
glomerular filtration rate
A blood-test estimate of how well the kidneys are filtering. Lower numbers mean reduced kidney function; many studies set a minimum value.
5 half-lives
The time it takes for the amount of a drug in the body to fall by half. 'Five half-lives' is often used as the point at which a previous drug has essentially left the body.
study drug
A treatment that is being tested and has not been approved for this use. It may be approved for a different condition. Being studied does not mean it works or is available outside the study.
enrollment
The number of participants a study plans to include, or has included. 'Estimated' means the planned number; 'actual' means the number who joined.
stable dose
A dose that has not changed for a defined period before the study starts. Studies may require this so that background treatment is relatively stable when study measurements begin.
screening period
The checks done before enrolment to see whether a person qualifies, such as tests, scans or a review of medical history.
electrocardiogram
A recording of the heart's electrical activity. QTc is one measurement from it; some drugs are avoided if it is prolonged.
Echocardiography
An ultrasound scan of the heart. A transesophageal echocardiogram is done through a probe passed into the food pipe for a closer view.
Inclusion Criteria
The conditions a person must meet to be considered for the study, for example a confirmed diagnosis, an age range or a test result.
Exclusion Criteria
The conditions that rule a person out even if they meet the inclusion criteria, for example other illnesses, certain medicines or pregnancy.
follow-up
The period after treatment or enrolment during which participants are observed or contacted, for example to record side effects or outcomes.

The study record on this page is reproduced from ClinicalTrials.gov, a database of the U.S. National Library of Medicine, where it was submitted by the study sponsor. MedicalUpdates.ai does not own this content, is not affiliated with or endorsed by ClinicalTrials.gov, NIH, or the U.S. Government, and does not verify the record. Plain-language notes, the glossary and the questions above are added by this site; text in the boxes marked "AI summary" was written by an AI model and may contain errors. Registry records change over time. Check the original record for the current version and discuss eligibility or participation with a qualified healthcare professional.

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