Background:
- Neurofibromatosis 1 (NF1) is an autosomal dominant disorder with an incidence of 1:3500
in the US. One of the cardinal features of NF1 is the development of histologically
benign peripheral nervesheath tumors called plexiform neurofibromas (PN) in 25-40% of
individuals with NF1. Unlike discrete neurofibromas, PN grow along the length of nerves
and involve multiple branches of a nerve. They are a major source of morbidity, causing
disfigurement, impairment of nerve function, pain, and in some cases development of
malignant peripheral nerve sheath tumors.
- Selumetinib (AZD6244) is a novel orally bioavailable mitogen activated protein kinase
inhibitor, is a specific inhibitor of MEK 1/2, which may mediate anti-tumor effects in
PN by inhibition of downstream signaling of Ras. Selumetinib is currently undergoing
evaluation in adult cancers and children with brain tumors and NF1-related plexiform
neurofibromas.
- In an NCI phase I trial of selumetinib for children and young adults with NF1 and
inoperable PN we have observed preliminary activity with PN volume decrease in >50% of
patients enrolled. This degree of activity has not been observed in prior trials
directed at PN. While preliminary activity has been seen in most patients enrolled to
date, in several patients who required (Bullet) 1 dose reduction for toxicity, after an
initial volume decrease, the PN volumes appear to be increasing slowly, and in one
patient a nodular appearing lesion is not responding to selumetinib. These findings
suggest that not all PN types may be responsive to selumetinib and that a certain
selumetinib tissue concentration may be required for target inhibition and anti-tumor
activity.
Objective:
-Determine the objective response rate (PN volume decrease greater than or equal to 20%
compared to baseline) to selumetinib in adult patients with inoperable PN.
Eligibility:
- Patients must be at least 18 years of age with a diagnosis of NF1, with an inoperable,
measureable PN that causes morbidity or is growing, which is amenable to percutaneous
biopsy, and must be willing to undergo two biopsies.
- Up to 10 patients who meet all criteria, but have PN, which cannot be biopsied safely,
will be eligible for the treatment portion of the study.
- Patients must have adequate organ function, be able to undergo serial MRI scans and have
recovered from acute toxicity of all prior treatment.
Design:
- This is a single site open label phase II study in which all subjects will receive
selumetinib orally approximately every 12 hours until patient develops progression of
disease, unacceptable toxicity or, in patients with non-progressive, symptomatic PN at
enrollment, a maximum of 2 years (unless they experience a partial response, or an
improvement in symptoms or function in which case they may continue until progression of
disease).
- Selumetinib will be administered at a dose of 50 mg BID on a continuous dosing schedule
(1 cycle=28 days), which is the recommended adult dose. A maximum accrual of 35
evaluable patients to meet the primary objective; while a maximum of 60 patients in
total may be enrolled to allow for a small number of screen failures, inevaluable
patients and up to 10 patients who cannot safely undergo two biopsies of PNs. Enrollment
will proceed over approximately 24 months.
- INCLUSION CRITERIA:
- Patients must have positive genetic testing for NF1in a CLIA certified laboratory or a
diagnosis of NF1 based on clinical NIH consensus criteria51 of at least one other
diagnostic criterion in addition to the presence of a PN. NF1 mutation analysis will
be performed on germline DNA as described by Messiaen & Wimmer 52. Histologic
confirmation of tumor is not necessary in the presence of consistent clinical and
imaging findings, but should be considered if malignant transformation of a PN is
clinically suspected. Additional criteria are as follows:
- Six or more cafe-au-lait macules (greater than or equal to 0.5cm in prepubertal
subjects or greater than or equal to1.5 cm in post pubertal subjects)
- Freckling in axilla or groin
- Optic glioma
- Two or more Lisch nodules
- A distinctive bony lesion (dysplasia of the sphenoid bone or dysplasia or
thinning of long bone cortex)
- A first-degree relative with NF1
- Measurable disease: Patients must have at least one measurable PN, defined as a lesion
of at least 3 cm measured in one dimension. Patients who underwent surgery for
resection of a PN are eligible provided the PN was incompletely resected and is
measurable as per criteria above. Measurability and suitability for volumetric MRI
analysis of the target PN must be confirmed with the NCI POB prior to enrolling a
patient. The target PN will be defined as the clinically most relevant PN, which has
to be amenable to volumetric MRI analysis. PN will be classified as typical PN versus
nodular PN versus solitary nodular PN prior to enrollment
- The PN must be inoperable, defined as a PN that cannot be surgically completely
removed without risk for substantial morbidity due to: encasement of or close
proximity to vital structures, invasiveness, or high vascularity of the PN. The PN
either causes morbidity or it is growing and has the potential to cause morbidity such
as (but not limited to): Head and neck lesions that could compromise the airway or
great vessels, paraspinal lesions that can cause myelopathy, brachial or lumbar plexus
lesions that could cause nerve compression and loss of function, lesions that could
result in major deformity (e.g., orbital lesions) or are significantly disfiguring,
and lesions of the extremity that cause limb hypertrophy or loss of function or pain.
PN growth will be defined as a greater than or equal to 20% increase in PN volume
within approximately 3 years prior to enrollment on this trial.
- Patients must have a PN amenable to a percutaneous biopsy to participate in the biopsy
portion of this study, and must be willing to undergo pre-, and on treatment tumor
biopsies. There should be no contraindication for serial biopsies. NOTE: Up to 10
patients who meet all criteria, but have PN which cannot be biopsied safely, will be
eligible for the treatment portion of the study.
- Must be able to undergo serial MRI scans for response evaluation
- Age greater than or equal to 18 years
- ECOG performance status less than or equal to 2 (Patients who are wheelchair bound
because of paralysis secondary to a plexiform neurofibroma should be considered
ambulatory when they are up in their wheelchair. Similarly, patients with limited
mobility secondary to need for mechanical support (such as an airway PN requiring
tracheostomy or CPAP) will also be considered ambulatory for the purpose of the
study.)
--ECOG Performance Status:*
- Grade/ECOG
- 0 Fully active, able to carry on all pre-disease performance without restriction
- 1 Restricted in physically strenuous activity but ambulatory and able to carry
out work of a light or sedentary nature, e.g., light house work, office work
- 2 Ambulatory and capable of all self-care but unable to carry out any work
activities. Up and about more than 50% of waking hours
- 3 Capable of only limited self-care, confined to bed or chair more than 50% of
waking hours
- 4 Completely disabled. Cannot carry on any self-care. Totally confined to bed or
chair
- 5 Dead
- As published in Am. J. Clin. Oncol.: Oken, M.M., Creech, R.H., Tormey, D.C.,
Horton, J., Davis, T.E., McFadden, E.T., Carbone, P.P.: Toxicity And
Response Criteria Of The Eastern Cooperative Oncology Group. Am J Clin Oncol
5:649-655, 1982.
- Patients must have normal organ and marrow function as defined below:
- hemoglobin greater than or equal to 10 g/dL (not requiring RBC transfusions)
- absolute neutrophil count greater than or equal to 1,500/mcL
- platelets greater than or equal to 100,000/mcL (not requiring platelet
transfusions)
- total bilirubin less than or equal to 1.5 upper limit of normal (ULN), with the
exception of patients with Gilbert Syndrome
- ALT(SGPT) & AST(SGOT) less than or equal to 3.0 X ULN
- upper limit of normal institutional limits
- OR
- creatinine clearance greater than or equal to 60 mL/min/1.73 m^2 for patients
with creatinine levels above institutional normal.
- Hematologic parameters for patients undergoing biopsy only: Patients should have INR
less than or equal to 1.4 and PT less than or equal to 40 seconds (unless due to lupus
anticoagulant). In patients not meeting these parameters, clearance by hematology will
be required prior to undergoing a biopsy.
- Cardiac Function: Normal ejection fraction (ECHO) greater than or equal to 53% (if a
range is given then the upper value of the range will be used) or cardiac MRI; QTcF
less than or equal to 450 msec.
- Ability of subject or Legally Authorized Representative (LAR)) to understand and the
willingness to sign a written informed consent document.
- Willingness to avoid excessive sun exposure and use adequate sunscreen protection if
sun exposure is anticipated.
- Willingness to avoid the ingestion of grapefruit and Seville oranges (as well as other
products containing these fruits, e.g. grapefruit juice or marmalade) during the
study.
- Prior therapy: Patients with NF1 will only be eligible if complete tumor resection is
not considered to be feasible without substantial risk or morbidity, or if a patient
with a surgical option refuses surgery.
- Since there is no standard effective chemotherapy for patients with NF1 and PN,
patients may be treated on this trial without having received prior medical
therapy directed at their PN.
- Since selumetinib is not expected to cause substantial myelosuppression, there
will be no limit to number of prior myelosuppressive regimen for PN or other
tumor manifestations associated with NF1 such as optic glioma.
- Patients who have received previous investigational agents or biologic therapy,
such as tipifarnib, pirfenidone, Peg-Intron, sorafenib, or other VEGFR inhibitors
are eligible for enrollment.
- Growth factors that support platelet or white cell number or function must not
have been administered within the past 7 days and are not permitted while on the
study.
- At least 6 weeks must have elapsed prior to enrollment since the patient received
any prior radiation therapy, and no prior radiation therapy should have been
directed at the target PN.
- At least 4 weeks must have elapsed since receiving medical therapy directed at
the PN.
- At least 4 weeks must have elapsed since any surgeries, with evidence of
completed wound healing.
- Patients who received prior medical therapy for their PN must have recovered from
the acute toxic effects of all prior therapy to less than or equal to grade 1
CTCAEv4 before entering this study.
- Informed Consent: Diagnostic or laboratory studies performed exclusively to determine
eligibility for this trial must only be done after obtaining written informed consent
from all patients, which can be accomplished using the screening consent for this
protocol. Studies or procedures that were performed for clinical indications (not
exclusively to determine eligibility) may be used for screening or baseline values
even if the studies were done before informed consent was obtained, if the patient
agrees.
EXCLUSION CRITERIA:
- Patients who are receiving any other investigational agents, or have received an
investigational agent within the past 30 days.
- May not have a NF1 related tumor such as optic pathway glioma or malignant peripheral
nerve sheath tumor, which requires treatment with chemotherapy or surgery.
- Uncontrolled intercurrent illness including, but not limited to, ongoing or active
infection, symptomatic congestive heart failure, unstable angina pectoris, cardiac
arrhythmia, active bleeding diatheses or renal transplant, including any patient known
to have hepatitis B, hepatitis C or human immunodeficiency virus (HIV), or psychiatric
illness/social situations that would limit compliance with study requirements.
Patients with HIV who have adequate CD4 counts and who have no requirement for
antiviral therapy will be eligible.
- Pregnant or breast-feeding females are excluded due to potential risks of fetal and
teratogenic adverse events of an investigational agent. Males or females of
reproductive potential may not participate unless they have agreed to use an effective
contraceptive method. Abstinence is an acceptable method of birth control.
- Prior treatment with selumetinib or another specific MEK 1/2 inhibitor.
- Supplementation with vitamin E greater than 100% of the daily recommended dose.
- Inability to swallow capsules, since capsules cannot be crushed or broken.
- Inability to undergo MRI and/or contraindication for MRI examinations following the
MRI protocol. Prosthesis or orthopedic or dental braces that would interfere with
volumetric analysis of target PN on MRI.
- Refractory nausea and vomiting, chronic gastrointestinal diseases (e.g., inflammatory
bowel disease), or significant bowel resection that would preclude adequate
absorption.
- Uncontrolled hypertension (despite medical therapy); blood pressure should be <140/90
in accordance with American Heart Association definition of hypertension.
- While not an exclusion criterion, unless clinically indicated, patients should avoid
taking other additional non-study medications that may interfere with the study
medications. In particular, patients should avoid medications that are known to either
induce or inhibit the activity of hepatic microsomal isoenzymes CYP1A2, CYP2C19 and
CYP3A4, as this may interfere with the metabolism of selumetinib.
- Known Cardiac Disorder, including:
- Known inherited coronary disease
- Symptomatic heart failure (NYHA Class II-IV prior or current cardiomyopathy, or
severe valvular heart disease)
- Current cardiomyopathy
- Severe valvular heart disease
- Atrial fibrillation
- Ejection fraction (ECHO) <53%
- QTcF >450 msec
- Known Ophthalmologic conditions, such as:
- Current or past history of central serous retinopathy
- Current or past history of retinal vein occlusion
- Known intraocular pressure (IOP) > 21 mmHg (or ULN adjusted by age) or
uncontrolled glaucoma (irrespective of IOP). Patients with known glaucoma and
increased IOP who do not have meaningful vision (light perception only or no
light perception) and are not experiencing pain related to the glaucoma, may be
eligible after discussion with the study chair.
- Subjects with any other significant abnormality on ophthalmic should be discussed
with the Study Chair for potential eligibility
- Ophthalmological findings secondary to long-standing optic pathway glioma (such
as visual loss, optic nerve pallor or strabismus) or long-standing
orbito-temporal PN (such as visual loss, strabismus) will NOT be considered a
significant abnormality for the purposes of the study
- Known severe hypersensitivity to selumetinib or any excipient of selumetinib or
history of allergic reactions attributed to compounds of similar chemical or biologic
composition to selumetinib
- Have had recent major surgery within a minimum of 4 weeks prior to starting study
treatment, with the exception of surgical placement for vascular access.
- Have any unresolved chronic toxicity with CTC AE grade greater than or equal to 2,
from previous anti-NF1 therapy, except for alopecia.
- Clinical judgment by the investigator that the patient should not participate in the
study
