-  Documentation of disease:

               -  Histologic documentation: histologically proven intracranial meningioma as
                  documented by central pathology review

               -  Molecular documentation: presence of SMO, PTCH1 or NF2 mutation in tumor sample
                  as documented by central laboratory

               -  Progressive OR residual disease, as defined by the following:

                    -  Residual measurable disease: residual measurable disease immediately after
                       surgery without requirement for progression; for grade I disease,
                       progression pre-operatively needs to be documented, with an increase in size
                       of the measurable primary lesion on imaging by 25% or more (bidirectional
                       area); the change must occur between scans separated by no more than 12
                       months; residual measurable disease will be defined by bidimensionally
                       measurable lesions with clearly defined margins by MRI scans, with a minimum
                       diameter of 10 mm in both dimensions

                    -  Progressive measurable disease: progression defined as an increase in size
                       of the measurable primary lesion on imaging by 25% or more (bidirectional
                       area); the change must occur between scans separated by no more than 12
                       months

                    -  Post radiation patients: patients with measurable and progressive meningioma
                       who have received radiation are potentially eligible, but need to show
                       evidence of progressive disease after completion of radiation; at least 24
                       weeks must have elapsed from completion of radiation to registration

          -  Measurable disease: measurable disease is defined by a bidimensionally measurable main
             lesion on MRI or computed tomography (CT) images (MRI preferred) with clearly defined
             margins; multifocal disease is allowed

          -  Prior treatment

               -  Prior medical therapy is allowed but not required

               -  No limit on number of prior therapies

               -  No chemotherapy, other investigational agents within 28 days of study treatment

               -  No other concurrent investigational agents or other meningioma-directed therapy
                  (chemotherapy, radiation) while on study

               -  For patients treated with external beam radiation, interstitial brachytherapy or
                  radiosurgery, an interval > 24 weeks must have elapsed from completion of
                  radiation therapy to registration

               -  Steroid dosing stable for at least 4 days

               -  Recovered to Common Terminology Criteria for Adverse Events (CTCAE) grade 1 or
                  less toxicity from other agents with exception of alopecia and fatigue

               -  No craniotomy within 28 days of registration

          -  Not pregnant and not nursing:

             * A female of childbearing potential is a sexually mature female who: 1) has not
             undergone a hysterectomy or bilateral oophorectomy; or 2) has not been naturally
             postmenopausal for at least 12 consecutive months (i.e., has had menses at any time in
             the preceding 12 consecutive months)

          -  Eastern Cooperative Oncology Group (ECOG) performance status =< 2

          -  Patient history:

               -  Patients with history of neurofibromatosis (NF) may have other stable central
                  nervous system (CNS) tumors (schwannoma, acoustic neuroma or ependymoma) if
                  lesions have been stable for 6 months

               -  No metastatic meningiomas (as defined by extracranial meningiomas) allowed

               -  No history of allergic reactions attributed to compounds of similar or biologic
                  composition to assigned study drug

               -  No known active hepatitis B or C

               -  No current Child Pugh class B or C liver disease

               -  No uncontrolled gastric ulcer disease (grade 3 gastric ulcer disease within 28
                  days of registration)

               -  No uncontrolled diabetes defined as a known diabetic with hemoglobin A1C (HBA1C)
                  > 7.5 OR fasting glucose > 140

               -  No uncontrolled hypertension defined as blood pressure (BP) > 140/90

               -  No abdominal fistula, gastrointestinal (GI) perforation, or intra-abdominal
                  abscess within 28 days prior to registration

          -  Concomitant medications:

               -  Chronic concomitant treatment with strong inhibitors of cytochrome P450, family
                  3, subfamily A, polypeptide 4 (CYP3A4) inhibitors must discontinue the drug for
                  14 days prior to registration on the study for patients with NF2 mutation
                  enrolled to GSK2256098

               -  Chronic concomitant treatment with strong CYP3A4 inducers is not allowed;
                  patients must discontinue the drug 14 days prior to the start of study treatment
                  for patients with NF2 mutation enrolled to GSK2256098

          -  Absolute neutrophil count (ANC) >= 1,500/mm^3

          -  Platelet count >= 100,000/mm^3

          -  Creatinine OR =< 1.5 mg/dl x upper limit of normal (ULN) OR calculated (calc.)
             creatinine clearance > 45 mL/min

          -  Urine protein:creatinine ratio (UPC) =< 45 mg/mmol; ONLY APPLICABLE for patients with
             NF2 mutation (GSK2256098)

          -  Total bilirubin =< 1.5 x upper limit of normal (ULN); except in case of Gilbert's
             disease

          -  Aspartate aminotransferase (AST)/alanine aminotransferase (ALT) =< 2.5 x upper limit
             of normal (ULN)

          -  Fasting triglyceride =< 200 mg/dL; ONLY APPLICABLE for patients with NF2 mutation
             (GSK2256098)

          -  Fasting cholesterol =< 240 mg/dL; ONLY APPLICABLE for patients with NF2 mutation
             (GSK2256098)

          -  Corrected QC interval calculated using Fridericia's formula (QTcF) =< 500 msec; ONLY
             APPLICABLE for patients with NF2 mutation (GSK2256098)