NCT05828069 · National Cancer Institute (NCI)
A Study With Tovorafenib (DAY101) as a Treatment Option for Progressive, Relapsed, or Refractory Langerhans Cell Histiocytosis
What this study is about
This phase II trial tests the safety, side effects, best dose and activity of tovorafenib (DAY101) in treating patients with Langerhans cell histiocytosis that is growing, spreading, or getting worse (progressive), has come back (relapsed) after previous treatment, or does not respond to therapy (refractory).
View original scientific description
This phase II trial tests the safety, side effects, best dose and activity of tovorafenib (DAY101) in treating patients with Langerhans cell histiocytosis that is growing, spreading, or getting worse (progressive), has come back (relapsed) after previous treatment, or does not respond to therapy (refractory). Langerhans cell histiocytosis is a type of disease that occurs when the body makes too many immature Langerhans cells (a type of white blood cell).
Who can participate
This study lists these criteria on ClinicalTrials.gov. A study coordinator reviews eligibility during screening — this page does not determine whether you qualify.
Inclusion criteria
- 180 days- \< 22 years (at time of study enrollment)
- Patient must have a body surface area of ≥ 0.3 m\^2
- Patients with progressive, relapsed, or recurrent LCH with measurable disease at study entry
- Patients must have had histologic verification of LCH (from either original diagnosis or relapse/progression) at the time of study entry (must be obtained within 28 days prior to enrollment and start of protocol therapy) (repeat if necessary)
- Tissue confirmation of relapse is recommended but not required
- Pathology report must be submitted for central confirmation of diagnosis within 7 days of enrollment.
- Formalin-fixed paraffin-embedded (FFPE) blocks or unstained slides (initial diagnosis and/or subsequent biopsies) will be required for retrospective central confirmation of diagnosis and molecular studies
- Patients with mixed histiocytic disorders (e.g. LCH with juvenile xanthogranuloma) may be included
- Patients must have measurable
Where
- Birmingham, Alabama
- Little Rock, Arkansas
- Downey, California
- Loma Linda, California
- Long Beach, California
- Los Angeles, California
- Madera, California
- Oakland, California
- Orange, California
- Palo Alto, California
- San Francisco, California
- Aurora, Colorado
And 74 more locations — see the full list below.
Frequently asked questions
What is a clinical trial?
A clinical trial is a research study that tests new medical treatments, drugs, devices, or procedures to determine their safety and effectiveness. Trials are carefully designed and monitored to protect participants while advancing medical knowledge.
Is it safe to participate?
Clinical trials follow strict safety guidelines and ethical standards. Trials must be reviewed and approved, and participants are closely monitored by medical professionals throughout the study. You can withdraw at any time if you choose.
Will I be compensated?
Many clinical trials offer compensation for your time, travel expenses, and inconvenience. The specific compensation varies by study and will be discussed during the screening process. All study-related medical care is typically provided at no cost to participants.
Will I receive a placebo instead of treatment?
When effective treatment exists, participants typically receive either the standard treatment plus the study intervention, or the standard treatment plus placebo. You would not be denied effective care. Placebos are primarily used when no proven treatment is available, or in addition to standard care. Your trial consent form will clearly explain what treatments you may receive.
Can I leave a trial if I change my mind?
Absolutely. Participation in clinical trials is completely voluntary. You have the right to withdraw from the study at any time, for any reason, without penalty or loss of benefits to which you are otherwise entitled.
How long does a clinical trial last?
Trial duration varies widely depending on the study design and purpose. Some trials last just a few weeks, while others may continue for months or years. The study coordinator will provide specific timeline information during your screening call.
Data: ClinicalTrials.gov · synced Jun 17, 2026 · Source of record for eligibility and locations