This pilot clinical trial studies dabrafenib and trametinib in treating patients with ameloblastoma and a specific mutation (change) in the BRAF gene. Dabrafenib and trametinib may stop the growth of tumor cells by blocking some of the enzymes needed for cell growth.
Completed
Phase 2
| Drug | Synonyms | Arms |
|---|---|---|
| Dabrafenib | BRAF Inhibitor GSK2118436, GSK-2118436A, GSK2118436, Tafinlar | Treatment (dabrafenib) |
| Trametinib | Mekinist | Treatment (dabrafenib) |
PRIMARY OBJECTIVES:
I. To observe the response rate of ameloblastoma to dabrafenib and trametinib at 6 weeks.
SECONDARY OBJECTIVES:
I. Feasibility and safety in this patient population. II. Response will be assessed
pathologically. III. Two main histologic assays for treatment response will be used: tumor
necrosis and phosphorylated-mitogen-activated protein kinase kinase 1 (MEK),
phosphorylated-extracellular signal-regulated kinase (ERK), and Ki-67 levels as measured by
immunohistochemistry.
OUTLINE:
Patients receive dabrafenib orally (PO) twice daily (BID) every 12 hours and trametinib 2 mg
daily PO for 6 weeks in the absence of disease progression or unacceptable toxicity. Patients
whose disease is judged to be not amenable to resection will continue dabrafenib and
trametinib indefinitely as long as there has not been tumor progression.
After completion of study treatment, patients are followed up for at least 4 weeks.
| Name | Type | Description | Interventions |
|---|---|---|---|
| Treatment (dabrafenib) | Experimental | Patients receive dabrafenib PO BID every 12 hours plus trametinib daily PO for 6 weeks in the absence of disease progression or unacceptable toxicity. Patients whose disease is judged to be not amenable to resection will continue dabrafenib and trametinib indefinitely as long as there has not been tumor progression. |
|
Inclusion Criteria:
- Histological diagnosis of ameloblastoma; all stages are eligible; patients must have
evaluable disease by Response Evaluation Criteria in Solid Tumors (RECIST) criteria
- B-Raf proto-oncogene, serine/threonine kinase (BRAF) V600E or other known dabrafenib
sensitive BRAF mutation in tumor by any Clinical Laboratory Improvement Amendments
(CLIA) certified lab; may include, for example, Sanger sequencing, SNaPshot platform,
immunohistochemistry, Foundation One tests, etc.)
- Life expectancy > 3 months
- Eastern Cooperative Oncology Group (ECOG) performance status ≤ 2
- Absolute neutrophil count (ANC) > 1.5 x10^9/L
- Platelet (PLT) > 99 x 10^9/L
- Hemoglobin > 8 g/dL
- Total bilirubin (Tbili) < 1.6 x upper limit of normal (ULN)
- Aspartate aminotransferase (AST), alanine aminotransferase (ALT) < 2.6 x ULN
- Alkaline phosphatase (alk phos) < 2.6 x ULN
- Serum creatinine < 1.6 x ULN or creatinine clearance > 50 ml/min
- Ability to understand and the willingness to sign a written informed consent document
- Patients of childbearing potential must agree to use effective contraception until at
least 6 months after treatment with dabrafenib
- Able to swallow and retain oral medication and must not have any clinically
significant gastrointestinal abnormalities that may alter absorption such as
malabsorption syndrome or major resection of the stomach or bowels
- Left ventricular ejection fraction equal to or greater than normal
Exclusion Criteria:
- No prior treatment with agents targeting BRAF mutant tyrosine kinases or radiation of
target lesions
- Invasive malignancy other than ameloblastoma within 3 years, excluding curatively
treated basal cell carcinoma, and other highly curable cancers such as early stage
cutaneous squamous cell carcinoma (T1 NO) cervical carcinoma in situ (CIS), early
stage prostate cancer, thyroid cancer or breast cancer
- Uncontrolled hypertension, chronic heart failure (CHF), or other major medical illness
- Prior allergic reactions attributed to compounds of similar chemical or biologic
composition to dabrafenib
- Concomitant use of strong inhibitors (e.g., ketoconazole, nefazodone, clarithromycin,
gemfibrozil) or strong inducers (e.g., rifampin, phenytoin, carbamazepine,
phenobarbital, St John's wort) of cytochrome P450, family 3, subfamily A, polypeptide
4 (CYP3A4) or cytochrome P450, family 2, subfamily C, polypeptide 8 (CYP2C8)
- Concomitant use of proton pump inhibitors, H2-receptor antagonists, antacids
- Known glucose-6-phosphate dehydrogenase (G6PD) deficiency
- Pregnant or nursing patients; women of childbearing potential must have a negative
pregnancy test within 14 days of enrollment
- Electrocardiogram (EKG) with QTcB (Bazett's formula) > 480 ms done within 14 days of
enrollment
- Interstitial lung disease or pneumonitis
- A history of retinal vein occlusion (RVO)
- Congestive heart failure NYHA class III or worse (Marked limitation of physical
activity. Comfortable at rest. Less than ordinary activity causes fatigue,
palpitation, or dyspnea.)
- A history of acute coronary syndromes (including myocardial infarction or unstable
angina), coronary angioplasty, or stenting within 6 months
| Maximum Eligible Age: | N/A |
| Minimum Eligible Age: | 18 Years |
| Eligible Gender: | All |
| Healthy Volunteers: | No |
| Measure: | Tumor Response |
| Time Frame: | 6 weeks |
| Safety Issue: | |
| Description: | Tumor response was assessed per the Response Evaluation Criteria in Solid Tumors (RECIST) v1.1. Overall tumor response was assessed as the number of participants achieving either a complete response (CR) or a partial response (PR). The criteria are: CR = Disappearance of all target lesions PR = ≥ 30% decrease in the sum of the longest diameter of target lesions Overall Response (OR) = CR + PR Progressive disease (PD) = 20% increase in the sum of the longest diameter of target lesions, and/or the appearance of one or more new lesion(s) Stable disease (SD) = Small changes that do not meet any of the above criteria The outcome is reported as the number of participants achieving the different levels of tumor response per RECIST, a number without dispersion. |
| Measure: | Percent Tumor Necrosis |
| Time Frame: | 6 weeks |
| Safety Issue: | |
| Description: | Percent of tumor necrosis at the time of endpoint biopsy or surgical resection will be assessed. The tumor specimen from resection will be examined and the volume of the necrosis compared to the volume of the total tumor determined by central pathology. Percent tumor necrosis, in increments of 10%, will be determined. The outcome will be reported as the mean percent tumor necrosis, with standard deviation. |
| Measure: | Change in Proliferation |
| Time Frame: | 6 weeks |
| Safety Issue: | |
| Description: | An immunohistochemical laboratory analysis to assess proliferation will be performed on the initial pre-treatment biopsy (baseline) vs either the endpoint tumor biopsy or the tumor specimen from the resection. Ki-67 immunohistochemistry will be scored by at least 2 pathologists using percentage positive cells as the primary metric. Proliferation will be assessed as the difference from baseline in Ki-67 labeling to the end of treatment (tumor biopsy or the tumor specimen). The outcome will be expressed as the mean, with standard deviation. |
| Measure: | Phosphorylation of Tumor Markers MEK and ERK |
| Time Frame: | 6 weeks |
| Safety Issue: | |
| Description: | An immunohistochemical laboratory analysis to assess phosphorylation of the tumor markers MEK and ERK on the initial pre-treatment biopsy (baseline) vs either the endpoint tumor biopsy or the tumor specimen from the resection. Immunohistochemistry will be scored by at least 2 pathologists using percentage positive cells and intensity of staining as the primary metrics. Phosphorylation of MEK and ERK will be assessed as the observed difference in phosphorylated MEK and ERK labeling from baseline to the end of treatment (tumor biopsy or the tumor specimen). The outcome will be expressed as the mean, with standard deviation. |
| Phase: | Phase 2 |
| Primary Purpose: | Interventional |
| Overall Status: | Completed |
| Lead Sponsor: | Stanford University |
January 21, 2020
