Inclusion Criteria:

- Histologically proven high grade glioma (WHO grade 3-4) which is progressive or
recurrent following radiation therapy with or without chemotherapy

- Patients with previous low grade glioma who progressed after radiotherapy and
chemotherapy and are biopsied and found to have a high grade glioma are eligible

- Patients must have recovered from toxicity of prior therapy - An interval of >=
3 months must have elapsed since the completion of the most recent course of
radiation therapy

- Minimum interval since last drug therapy: 2 weeks since last non-cytotoxic therapy; 3
weeks must have elapsed since the completion of a non-nitrosourea containing
chemotherapy regimen; 6 weeks since the completion of a nitrosourea containing
chemotherapy regimen

- Patients must have a Karnofsky performance status >= 60% (i.e., must be able to care
for himself/herself with the occasional help of others)

- Patients must have normal hematologic, renal, and liver function (i.e., absolute
neutrophil count >= 1500/mm^3, platelets >= 100,000/mm^3, HgB > 9 d/dl, creatinine =<
1.5mg/dl, total bilirubin =< 1.5mg/dl, transaminases =< 2.5 times the upper limits of
the institutional norm)

- Patients must be able to provide written informed consent

- Patients with the potential for pregnancy or impregnating their partner must agree to
follow acceptable birth control methods to avoid contraception - Female patients
of child-bearing potential must have a negative pregnancy test

- Patients must have no concurrent malignancy except curatively treated basal or
squamous cell carcinoma of the skin of carcinoma in situ of the cervix and breast,
adequately treated stage I or II cancer from which the patient is in complete
remission

- Patients with other prior malignancies must be disease-free for >= 3 years

- Patients must be maintained on a stable corticosteroid regimen from the time of their
baseline scan until the start of treatment

- Patients must have a Mini mental state exam score >= 15

Exclusion Criteria:

- Patients with serious concurrent infection or medical illness, which would jeopardize
the ability of the patient to receive the treatment outlines in this protocol with
reasonable safety

- Patients who are pregnant or breast-feeding

- Patients receiving concurrent therapy for their tumor (with the exception of
steroids)

- HIV positive

- Prior therapy with HIV protease inhibitors

- Concurrent therapy with hepatic enzyme inducing anticonvulsant

- Inability to be followed closely at the Cleveland Clinic

- Patients requiring the use of medication well-known contraindicated for concomitant
use with lopinavir/ritonavir: amiodarone, astemizole, bepridil, bupropione,
cisapride, clorazepate, clozapim, diazepam, encainide, flecainide, flurazepam,
meperidine, midazolam, primozide, piroxicam, propafenone, propoxifeno, quinidine,
rifabutin, terfenadine, triazolam, zolpidem, dihydroergotamine, ergotamine