MLN9708 and Dexamethasone for High-Risk Smoldering Multiple Myeloma

Background:

- SMM is a precursor condition to MM defined by the clinical parameters of M-protein
greater than or equal to 3.0 g/dL or bone marrow plasma cells greater than or equal to
10% and absence of end organ disease.

- Risk of progression of high risk SMM at 5 years is 72-75% with median time to
progression less than 2 years.

- The current standard of care for SMM is close follow-up without treatment until
symptomatic MM develops. However, IMWG states Preventive clinical trials need to be
considered for patients with high risk smoldering myeloma .

- MLN9708 is a new oral proteasome inhibitor with potent anti-MM effects

Objectives:

Primary Endpoint:

-The primary objective of the study is to assess the response rate of MLN9708/low-dose

dexamethasone in patients with high-risk SMM.

Secondary Endpoints:

- To determine progression free survival (PFS)

- To determine duration of response (DOR)

- To evaluate toxicity of combination therapy (MLN9708 and low-dose dexamethasone).

- To evaluate biological activity of MLN9708 and correlate to clinical outcomes (gene
expression profiling and proteasome activity and ubiquination assays, and effects on
downstream signaling targets using pre- and post-MLN9708 exposure bone marrow samples)

Eligibility:

- SMM according to the International Myeloma Working Group definition i.e.:

- Serum M-protein greater than or equal to 3 g/dl and/or bone marrow plasma cells
greater than or equal to 10 %,

- Absence of anemia: Hemoglobin greater than10 g/dl

- Absence of renal failure: calculated creatinine clearance (according to MDRD)
greater than 80 ml/min (or alternatively based on standard creatinine level
criteria of 2 mg/dl)

- Absence of hypercalcemia: Ca < 10.5 mg/dl or less than or equal to 2.5 mmol/L

- Absence of lytic bone lesion

- Measurable disease within the past 4 weeks defined by any one of the following:

- Serum monoclonal protein greater than or equal to 1.0 g/dl

- Urine monoclonal protein > 200 mg/24 hour

- Serum immunoglobulin free light chain > 10 mg/dL AND abnormal kappa/lambda ratio
(reference 0.26-1.65)

- High-risk SMM per Mayo Clinic or Spanish PETHEMA criteria

- Age greater than18 years

- Eastern Cooperative Oncology Group (ECOG) performance status 0-2

- Ability to give informed consent

- Patients must have normal organ and marrow function as defined below:

- absolute neutrophil count greater than1.0 K/uL

- platelets greater than75 K/uL (Platelet transfusions to help patients meet
eligibility criteria are not allowed within 3 days before study enrolment.)

- hemoglobin greater than 8 g/dL(transfusions are permissible)

- total bilirubin less than1.5 X institutional upper limit of normal

- AST(SGOT)/ALT(SGPT) less than 3.0 X institutional upper limit of normal

Design:

-Single arm pilot trial of combination therapy (MLN9708 and dexamethasone) for high risk
smoldering multiple myeloma

- Patients will receive 12 cycles (28 days each) of induction combination therapy of
MLN9708 and low-dose dexamethasone. After 12 cycles of MLN9708/low-dose dexamethasone,
patients will receive MLN9708 maintenance until progression or unacceptable toxicity.

- Patients will have routine blood work with SPEP and free light chains monthly

- Pre- and post-treatment bone marrow biopsies will be obtained for confirmation of
diagnosis and correlative studies

- Patients will also undergo evaluation for minimal residual disease at complete
remission/completion of 12 cycles of therapy, using multi-parametric flow cytometry and
FDG PET-CT

- This single arm pilot study will enroll 12 evaluable patients and determine M-spike
levels on each patient immediately pre-treatment as well as after completing 12 cycles
of treatment. The study aim is to find 9 or more patients (out of 12) with a partial
response (PR) or better; which would provide strong evidence that the true probability
of an overall response is consistent with 80% or more.

- INCLUSION CRITERIA:

- Patients must have histologically or cytologically confirmed Smoldering Multiple
Myeloma confirmed by the Laboratory of Pathology, NCI based on the International
Myeloma Working Group Criteria:

- Serum M-protein greater than or equal to 3 g/dl and/or bone marrow plasma cells
greater than or equal to 10 %,

- Absence of anemia: Hemoglobin > 10 g/dl

- Absence of renal failure: calculated creatinine clearance (according to MDRD) >
80 ml/min (or alternatively based on standard creatinine level criteria of 2
mg/dl)

- Absence of hypercalcemia: Ca < 10.5 mg/dl or less than or equal to 2.5 mmol/L

- Absence of lytic bone lesion

- High-risk SMM per Mayo Clinic2 or Spanish PETHEMA1 criteria

- Measurable disease within the past 4 weeks defined by any one of the following:

- Serum monoclonal protein greater than or equal to 1.0 g/dl

- Urine monoclonal protein > 200 mg/24 hour

- Serum immunoglobulin free light chain > 10 mg/dL AND abnormal kappa/lambda ratio
(reference 0.26-1.65)

- Age > 18 years.

- ECOG performance status < 2.

- Ability to give informed consent.

- Patients must have normal organ and marrow function as defined below:

- absolute neutrophil count > 1.0 K/uL

- Platelets > 75 K/uL (Platelet transfusions to help patients meet eligibility
criteria are not allowed within 3 days before study enrollment.)

- hemoglobin > 8 g/dL(transfusions are permissible)

- total bilirubin < 1.5 X institutional upper limit of normal

- AST(SGOT)/ALT(SGPT) < 3.0 X institutional upper limit of normal

- Female patients who:

- Are postmenopausal for at least 1 year before the Screening visit, OR

- Are surgically sterile, OR

- If they are of childbearing potential, agree to practice 2 effective methods of
contraception, at the same time, from the time of signing the informed consent
through 30 days after the last dose of study treatment, OR agree to completely
abstain from heterosexual intercourse.

- The 2 methods of reliable contraception must include 1 highly effective
method and 1 additional effective (barrier) method. Females of childbearing
potential must be referred to a qualified provider of contraceptive methods
if needed. The following are examples of highly effective and additional
effective methods of contraception:

- Highly effective methods:

- Intrauterine device (IUD)

- Hormonal (birth control pills, injections, implants)

- Tubal Ligation

- Partner's Vasectomy

Additional effective methods:

- Male condom

- Diaphragm

- Cervical Cap

-Male patients, even if surgically sterilized (i.e., status post-vasectomy), who:

- Agree to practice effective barrier contraception during the entire study treatment
period and through 4 months after the last dose of study treatment, OR agree to
completely abstain from heterosexual intercourse.

EXCLUSION CRITERIA:

- Patients who are receiving any other investigational agents not included in this
trial, within 21 days of the start of this trial and throughout the duration of this
trial.

- Prior therapy for SMM with a proteasome inhibitor.

- Patients with a diagnosis of MM.

- Contraindication to any concomitant medication, including antivirals, anticoagulation
prophylaxis, tumor lysis prophylaxis, or hydration given prior to therapy.

- Known allergy to any of the study medications, their analogues, or excipients in the
various formulations of any agent.

- Uncontrolled hypertension or diabetes.

- Pregnant or lactating females.

- Has refractory GI disease with refractory nausea/vomiting, inflammatory bowel
disease, or bowel resection that would prevent absorption.

- Patient has greater than or equal to Grade 2 peripheral neuropathy.

- Evidence of current uncontrolled cardiovascular conditions, including uncontrolled
hypertension, uncontrolled cardiac arrhythmias, symptomatic congestive heart failure,
unstable angina, or myocardial infarction within the past 6 months.

- Systemic treatment, within 14 days before study enrollment, with strong inhibitors of
CYP1A2 (fluvoxamine, enoxacin, ciprofloxacin), strong inhibitors of CYP3A
(clarithromycin, telithromycin, itraconazole, voriconazole, ketoconazole, nefazodone,
posaconazole) or strong CYP3A inducers (rifampin, rifapentine, rifabutin,
carbamazepine, phenytoin, phenobarbital), or use of Ginkgo biloba or St. John s
wort.

- Ongoing or active systemic infection, known human immunodeficiency virus (HIV)
positive, known active hepatitis B virus hepatitis, or known active hepatitis C virus
hepatitis.

- Co-morbid systemic illnesses or other severe concurrent disease that, in the judgment
of the investigator, would make the patient inappropriate for entry into this study
or interfere significantly with the proper assessment of safety and toxicity of the
prescribed regimens.

- Psychiatric illness/social situation that would limit compliance with study
requirements.

- QTc > 470 milliseconds (msec) on a 12-lead EKG obtained during the Screening period.
If a machine reading is above this value, the EKG should be reviewed by a qualified
reader and confirmed on a subsequent EKG.

- Diagnosed or treated for another malignancy within 2 years before study enrollment or
previously diagnosed with another malignancy and have any evidence of residual
disease. Patients with non-melanoma skin cancer or carcinoma in situ of any type are
not excluded if they have undergone complete resection.

- Inability to swallow oral medication, inability or unwillingness to comply with the
drug administration requirements or GI procedure that could interfere with the oral
absorption or tolerance of treatment.

- Major surgery within 1 month prior to enrollment.

- Radiotherapy within 14 days before enrollment.

- Central nervous system involvement (based on clinical assessment).

- Infection requiring systemic antibiotic therapy or other serious infection within 14
days before study enrollment.

- No current bisphosphonate therapy (However, prior bisphosphonates or once a year
intravenous bisphosphonate for osteoporosis is allowed).

- Patients with Paget s disease of the bone

- Recruitment Strategies

- Patients from the SMM and MGUS Natural History Study (NCI Protocol: 10-C-0096) will
be potential candidates.

- Other participant sources will be from outside physician referrals.

- Our ongoing natural history study and outside physician referral network have a high
representation of minorities.