Overview

Mirdametinib in Histiocytic Disorders

Status:
Recruiting
Trial end date:
2031-03-01
Target enrollment:
0
Participant gender:
All
Summary
The purpose of this study is to see if treatment with mirdametinib in patients with Langerhans cell histiocytosis (LCH) or other histiocytic disorders will be better than current treatments and with fewer side effects.
Phase:
Phase 2
Accepts Healthy Volunteers?
No
Details
Lead Sponsor:
Children's Hospital Medical Center, Cincinnati
Criteria
Inclusion Criteria:

1. All subjects must have a biopsy-proven diagnosis of histiocytic neoplasm confirmed by
a Cincinnati Children's Hospital Medical Center (CCHMC) pathologist. The only
exception is those with isolated pituitary/CNS disease where biopsy is not feasible.
Biopsy material must be available from either diagnosis or relapse. The subjects must
have LCH, JXG, RDD, or other histiocytosis with a known activating mutation in
mitogen-activated protein (MAP) kinase pathway genes such as RAS, RAF or MAP2K1. Each
patient must have tissue available for mutational analysis if not done prior to study
enrollment.

2. Subjects must have disease that requires systemic therapy such as:

- multi-system disease (with or without risk-organ involvement)

- multi-focal bone disease

- isolated CNS/pituitary disease

- CNS-risk lesion (single bone lesion in the skull outside of the calvarium, which
puts a patient at risk of developing CNS disease, this is different from isolated
CNS-LCH)

- Special site (solitary bone lesion in a precarious location such as the odontoid
process, neck-of-femur)

3. Measurable disease: as evidenced by PET scan, brain MRI (for active CNS disease)

4. Age: Subjects must be ≥ 2 years of age at the time of study entry.

5. Durable Power of Attorney: Adults who are unable to provide informed consent will NOT
be enrolled on this study.

6. Subjects may have been previously treated for histiocytosis with chemotherapy,
surgery, glucocorticoids, or MAP kinase pathway inhibitors but with washout periods as
described below:

- Myelosuppressive Chemotherapy: must not have received any cytotoxic chemotherapy
which impacts the growth and development of cells in the bone marrow including,
but not limited to, cytarabine, cladribine, clofarabine, mercaptopurine,
methotrexate or vinblastine within 14 days of enrollment onto this study.

- Biologic (Anti-Neoplastic Agent): Must not have received biologic agent within 30
days (or 5 half-lives, whichever is longer) of enrollment into this study. For
agents that have known adverse events occurring beyond 14 days after
administration, this period must be extended beyond the time during which adverse
events are known to occur. These subjects must be discussed with the Protocol
Chair on a case-by-case basis.

- Investigational Drugs: Subjects must not have received an investigational drug
within 30 days of study enrollment.

- Steroids: Subjects with endocrine deficiencies are allowed to receive physiologic
or stress doses of steroids if necessary. Chronic topical or systemic steroid use
outside of this indication are not permitted.

- Glucocorticoids: Due to the increased risk of an ocular event, the use of
systemic oral, inhaled, or ocular glucocorticoid therapy is prohibited within the
14 days prior to first dose of mirdametinib and throughout the treatment period.

- XRT: Subjects who have received radiation to the orbit at any time are excluded.

- Surgery: Must demonstrate adequate post-operative recovery, approaching
pre-operative state of health with appropriate wound healing and minimal residual
side effects.

7. Organ Function Requirements

- Adequate Renal Function defined as: maximum serum creatinine 2x ULN for age OR a
creatinine clearance or radioisotope GFR ≥ 70ml/min/1.73 m2

- Adequate Liver Function defined as: ALT ≤ 3x ULN AND normal INR

- Adequate hematologic and end-organ function: Hematology: Albumin ≥ 2.8 g/dL;
Hemoglobin ≥ 9.0 g/dL; Absolute neutrophil count ≥ 1.5 x 109/L; Platelets ≥ 100 x
109/L, except where bleeding leading to low hemoglobin level is an indication for
treatment, in which case hemoglobin < 9.0 g/dL is acceptable

Exclusion Criteria:

1. Chronic treatment with systemic steroids or another immunosuppressive agent. Subjects
with endocrine deficiencies are allowed to receive physiologic or stress doses of
steroids if necessary.

2. Subjects who have received radiation within 14 days of study enrollment.

3. Subjects who have received radiation to the orbit at any time previously.

4. Subjects requiring glucocorticoids. Due to the increased risk of an ocular event, the
use of systemic, inhaled, or ocular glucocorticoid therapy is prohibited within the 14
days prior to first dose of mirdametinib and throughout the treatment period.

5. Subjects with glaucoma, or any other significant abnormality on ophthalmic examination
classified as ≥ grade 2, and uncontrolled with intervention (evaluation/management by
an ophthalmologist).

6. Participant has a history of, or evidence of, retinal pathology on ophthalmologic
examination that is considered a risk factor for central serous retinopathy, retinal
vein occlusion (RVO), or neovascular macular degeneration. Participants will be
excluded from study participation if they have any of the following risk factors for
RVO at Screening:

- Intraocular pressure > 21 mmHg;

- Serum cholesterol > 300 mg/dL;

- Serum triglycerides > 300 mg/dL;

- Hyperglycemia (fasting blood glucose > 125 mg/dL or random blood glucose > 200
mg/dL);

- Age specific hypertension

- Participants ≥ 13 years of age with a blood pressure ≥ 140/90 mm Hg

- Participants ≤ 12 years of age with a blood pressure ≥ 95th percentile for
age +12 mmHg;

7. Participant has recorded a LVEF < 55% at Screening or within 3 years of signing
informed consent/assent, OR has a history of congestive heart failure;

8. History (within 6 months before the start of the study treatments) of clinically
significant cardiac disease (New York Heart Association Class III or IV), myocardial
infarction, severe/unstable angina, coronary/peripheral artery bypass graft,
symptomatic congestive heart failure, cerebrovascular accident, clinically significant
transient ischemic attack, symptomatic pulmonary embolism, unexplained syncope, or
long QT syndrome

9. History or current evidence of an active parathyroid disorder, or of
malignancy-associated Grade ≥2 hypercalcemia despite optimal remedial therapy.

10. Absence of measurable disease (clinical or radiologic)

11. Other concurrent severe and/or uncontrolled medical disease, which could compromise
participation in the study (e.g., uncontrolled diabetes, uncontrolled hypertension,
uncontrolled hypercholesterolemia, uncontrolled hypertriglyceridemia, uncontrolled or
severe infection, severe malnutrition, chronic liver or renal disease unrelated to
histiocytosis, congestive heart failure, etc.)

12. Women who are pregnant or breast feeding.

13. Males or females of reproductive potential may not participate unless they have agreed
to use a highly effective contraceptive method during the period they are receiving
the study drug and for 6 months thereafter. Abstinence, barrier (use of condom by male
partner of female patient), implantable and oral forms of contraception are acceptable
methods of birth control. Women of childbearing potential will be given a pregnancy
test within 7 days prior to administration of mirdametinib and must have a negative
serum pregnancy test.

14. Subjects unwilling to or unable to comply with the protocol, or who in the opinion of
the investigator may not be able to comply with the safety monitoring requirements of
the study

15. Previously treated with a MEK inhibitor including mirdametinib (PD-0325901) and had to
stop treatment due to disease progression.

16. Currently receiving therapy with a MEK inhibitor including mirdametinib (PD-0325901)
or treated with a MEK inhibitor within 30 days or 5 half-lives (whichever is greater)
prior to first dose of study treatment

17. Patients who have a MAP2KI mutation that is known to not be responsive to MEK
inhibitors, such as mutations affecting amino acid residues 98-104 of the MEK protein

18. Patients that enroll in the study who do not have mutation analysis prior to study
entry may still enroll in study if tissue available for mutational analysis. If they
are found to have a mutation known to be resistant to MEK inhibitors such as mutations
involving amino acid residues 98-104 of the MEK protein, known to be unresponsive to
MEK inhibitors, they will be taken off study, and replacement patients added. These
mutations have been reported in the literature and believed to be exceedingly rare.
The potential benefit of mirdametinib outweighs the risk of starting therapy in a
patient prior to knowledge of mutation data. In the unlikely event a patient is found
to have this specific, unresponsive mutation, therapy would be discontinued.