RecruitingLangerhan's Cell HistiocytosisJuvenile XanthogranulomaErdheim-Chester Disease

Cobimetinib in Refractory Langerhans Cell Histiocytosis (LCH), and Other Histiocytic Disorders

Eligible age

All ages

Accepts

All genders

Locations

10 states

Healthy volunteers

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About this study

This is a research study of a drug called cobimetinib in children and adults diagnosed with Langerhans cell histiocytosis (LCH), and other histiocytic disorders that has returned or does not respond to treatment. Cobimetinib blocks activation of a protein called Mitogen-activated protein kinase (MEK) that is part of incorrect growth signals in histiocytosis cells. Four different groups of patients will be enrolled.

Sponsor: Carl Allen

You may qualify if…

✓ Age at study entry
✓ For Group 1: Participant must be at least 6 months of age and less than 21 years of age at the time of enrollment
✓ For Group 2: Participant may be at least 6 months of age at the time of enrollment
✓ For Group 3: Participant must be at least 6 months of age and less than 21 years of age at the time of enrollment
✓ For Group 4: Participant must be 21 years of age or older at the time of enrollment
✓ Participant must be able to take an enteral dose and formulation of medication. Study medication is only available as an oral suspension or tablet which may be taken by mouth or other enteral route such as nasogastric or gastric tube.
✓ As of 27Feb2026, due to suspension no longer being available, subject must be able to swallow tablets.
✓ Biopsy proven LCH -AND

You may not qualify if…

✕ \- Prior and Concomitant Use of Drugs with CYP3A4 inducing/inhibiting activity: Patient taking strong inducers or inhibitors of CYP3A4 within 14 days prior to study enrollment, including but not limited to the following: erythromycin, clarithromycin, ketoconazole, azithromycin, itraconazole, grapefruit juice or St. John's wort.
✕ Prior Therapy Restrictions Completion of previous chemotherapy, immunotherapy, radiotherapy, or targeted therapy for LCH (or other histiocytic disorder) at least 28 days (except where specified below) prior to study enrollment, with resolution of all associated toxicity to ≤ Grade 1 prior to study enrollment (exception for alopecia and ototoxicity which do not need to be resolved ≤ Grade 1). Patients must have fully recovered from the acute toxic effects of all prior anti-cancer therapy and must meet the following minimum duration from prior anti-cancer directed therapy prior to enrollment. If after the required timeframe, the laboratory eligibility criteria are met, the patient is considered to have recovered adequately. See below for specific consideration of prednisone and corticosteroids prior to enrollment.
✕ Radiation therapy within the 14 days prior to enrollment.
✕ Any prior treatment with Cobimetinib.
✕ Treatment with a long-acting hematopoietic growth factor within 14 days prior to initiation of study drug or a short-acting hematopoietic growth factor within 7 days prior to enrollment.
✕ Treatment with hormonal therapy (except hormone replacement therapy or oral contraceptives), immunotherapy, biologic therapy, investigational therapy, or herbal cancer therapy within 28 days or \< 5 half-lives, whichever is longer, prior to study enrollment.
✕ Treatment with high-dose chemotherapy and stem-cell rescue (autologous stem cell transplant) or allogeneic stem cell transplant within 90 days prior to enrollment. Anti-GVHD agents post-transplant: Patients who are receiving cyclosporine, tacrolimus or other agents to prevent graft-versus-host disease post bone marrow transplant are not eligible for this trial.
✕ For patients with brain tumors (intracranial masses), use of anticoagulants within 7 days prior to enrollment.