The purpose of the study is to test the efficacy and tolerability of a combination treatment
of methotrexate, ibrutinib, and temozolomide (MIT regimen) in treating patients who have
newly-diagnosed primary CNS lymphoma.
Primary central nervous system lymphoma (PCNSL) is a rare and aggressive extranodal
Non-Hodgkin Lymphoma. Induction treatment of PCNSL in most reported single-arm or randomized
trials includes high-dose methotrexate (HD-MTX)-based therapy, temozolomide, with or without
cytarabine and the anti-CD20 antibody rituximab. A better combination remains undefined.
Treatment is associated with considerable morbidity and disease recurrences with a 5-year
survival of approximately 40%.
The BTK inhibitor ibrutinib has shown antitumor activity in patients with recurrent or
refractory PCNSL. However, tumor responses to single-agent ibrutinib in CNS lymphoma are
often incomplete or transient. Efficacy and safety of ibrutinib in combination with cytotoxic
agents are worth to be discovered. Grommes et al.have shown ibrutinib in combination with
methotrexate and rituximab are safe and shows promising activity in recurrent/refractory CNS
lymphoma. In comparison to their prior study with single-agent ibrutinib, the radiographic
response of r/r PCNSL was higher with the ibrutinib/HD-MTX/rituximab combination regimen and
PFS was longer with the combination therapy. The study has shown that ibrutinib combined with
chemotherapy were superior to ibrutinib single agent and overcome the transient effect of
ibrutinib in relapsed PCNSL. However, there are some limitations in interpreting Grommes'
study results, especially the heterogeneous patient population with inclusion of both PCNSL
and SCNSL. Most recently, the role of rituximab in PCNSL has become clearly. In the HOVON
105/ALLG NHL 24 study, the addition of rituximab to a methotrexate-based regimen did not
demonstrate a significant benefit on clinical outcome. We therefore initiate this study aim
to evaluate the activity and safety of ibrutinib in combination with Methotrexate and
temozolomide (MIT regimen) in newly diagnosed PCNSL patients.
Inclusion Criteria:
- Men and woman who are 18 to 70 years of age on the day of consenting to the study.
- Histologically documented PCNSL
- ECOG performance status ≤ 2.
- Life expectancy of > 3 months (in the opinion of the investigator).
- Adequate bone marrow and organ function shown by:
- Absolute neutrophil count (ANC) ≥ 1.5 x 10^9/L
- Platelets ≥ 75 x 10^9/L and no platelet transfusion within the past 14 days prior
to study registration
- Hemoglobin (Hgb) ≥ 8 g/dL and no red blood cell (RBC) transfusion within the past
14 days prior to study registration
- International Normalized Ratio (INR) ≤ 1.5 and PTT (aPTT) ≤ 1.5 times the upper
limit of normal
- Alanine aminotransferase (ALT) and aspartate aminotransferase (AST) ≤ 3 times the
upper limit of normal
- Serum bilirubin ≤ 1.5 times the upper limit of normal; or total bilirubin ≤ 3
times the upper limit of normal with direct bilirubin within the normal range in
patients with well documented Gilbert Syndrome
- Serum creatinine ≤ 2 times the upper limit of normal
- Lipase ≤ 1.5 x upper limit of normal
- Women of childbearing potential (WOCBP) and men must agree to use effective
contraception when sexually active. This applies for the time period between signing
of the informed consent form and 30 days (for WOCBP) and 90 days (for men) after the
last administration of study treatment. A woman is considered of childbearing
potential, i.e. fertile, following menarche and until becoming post-menopausal unless
permanently sterile. Permanent sterilization methods include but are not limited to
hysterectomy, bilateral salpingectomy and bilateral oophorectomy. A postmenopausal
state is defined as no menses for continuous 12 months without an alternative medical
cause. A high follicle stimulating hormone (FSH) level in the postmenopausal range may
be used to confirm a post-menopausal state in women not using hormonal contraception
or hormonal replacement therapy.
- The investigator or a designated associate is requested to advise the patient how
to achieve highly effective birth control (failure rate of less than 1%), e.g.
intrauterine device (IUD), intrauterine hormone-releasing system (IUS), bilateral
tubal occlusion, vasectomized partner and sexual abstinence
- The use of condoms by male patients is required unless the female partner is
permanently sterile. Female subjects of childbearing potential must have a
negative plasma pregnancy test upon study entry
- Must be able to tolerate MRI/CT scans
- Must be able to tolerate lumbar puncture and/or Ommaya taps
- Able to submit up to 20 unstained formalin-fixed, paraffin-embedded (FFPE) slides from
the initial or most recent tissue diagnosis for correlative studies
Exclusion Criteria:
Patients eligible for this study must NOT MEET ANY of the following criteria:
• Active concurrent malignancy requiring active therapy
Excluded medical conditions:
- Clinically significant cardiovascular disease such as uncontrolled or symptomatic
arrhythmias, congestive heart failure (New York Heart Association > Class 2), unstable
angina, or myocardial infarction within 6 months of screening, or any Class 3 or 4
cardiac disease as defined by the New York Heart Association Functional Classification
- Uncontrolled hypertension despite optimal medical management (per investigators
assessment)
- Patient has poorly controlled diabetes mellitus with a glycosylated hemoglobin >8% or
poorly controlled steroid-induced diabetes mellitus with a glycosylated hemoglobin of
>8%
- Patient is known to have an uncontrolled active systemic infection (>CTCAE grade 2)
and recent infection requiring intravenous anti-infective treatment that was completed
≤14 days before the first dose of study drug
- Arterial or venous thrombotic or embolic events such as cerebrovascular accident, deep
vein thrombosis or pulmonary embolism within 3 months before the start of study
treatment
- Non-healing wound, ulcer or bone fracture
- Known bleeding diathesis (eg, von Willebrands disease) or hemophilia
- Known history of infection with human immunodeficiency virus (HIV) or active stage of
infection with hepatitis C virus (HCV) or hepatitis B virus (HBV) as determined by
serologic tests, or any uncontrolled active systemic infection
- Patient underwent major systemic surgery ≤ 2 weeks prior to starting the trial
treatment or who has not recovered from the side effects of such surgery, or who plan
to have surgery within 2 weeks of the first dose of the study drug
- Unable to swallow capsules or disease significantly affecting gastrointestinal
function, such as malabsorption syndrome, resection of the stomach or small bowel, or
complete bowel obstruction
- Any life-threatening illness, medical condition including uncontrolled diabetes
mellitus (DM), uncontrolled hypertension or organ system dysfunction that, in the
opinion of the investigator, could compromise the subjects safety or put the study
outcomes at undue risk
- Lactating or pregnant
Excluded previous Therapies and medications:
- Concurrent use of warfarin or other vitamin K antagonists (need to be stopped 7 days
prior to starting on trial drug)
- Concurrent use of a strong cytochrome P450 (CYP) 3A4/5 inhibitor and inducers (need to
be stopped 2 weeks prior to starting on trial drug)
- Enzyme-inducing antiepileptic drugs (EIAED) need to be discontinued and switched to a
non-EIAED 2 weeks prior to starting on trial drug)
- Patient requires more than 4 mg of dexamethasone daily or the equivalent
- Patient is using systemic immunosuppressant therapy, including cyclosporine A,
tacrolimus, sirolimus, and other such medications, or chronic administration of > 5
mg/day or prednisone or the equivalent. Participants must be off of immunosuppressant
therapy for at least 28 days prior to the first dose of the study drug
- Concurrent systemic immunosuppressant therapy (eg, cyclosporine A, tacrolimus, etc.,
or chronic administration of > 5 mg/day of prednisone) within 28 days of the first
dose of study drug
