Study Evaluating the Safety and Tolerability of Weekly Dosing of Oral IXAZOMIB in Adult Patients With Relapsed and Refractory Multiple Myeloma

Inclusion Criteria:

Each patient must meet all of the following eligibility criteria to be enrolled in the study:

* Adult patients with multiple myeloma who have relapsed following at least 2 lines of therapy.
* Patients must have measurable disease.
* Appropriate functional status, including the recovery from the effects of prior antineoplastic therapy, and acceptable organ function as described in the protocol.
* Female patients who are post menopausal, surgically sterile, or agree to practice 2 effective methods of contraception or abstain from heterosexual intercourse.
* Male patients who agree to practice effective barrier contraception or agree to abstain from heterosexual intercourse.
* Willing and able to give written informed consent.
* Suitable venous access for study-required blood sampling.

Exclusion Criteria:

* Peripheral neuropathy that is greater or equal to Grade 2.
* Major surgery or, serious infections, or infections that required systemic antibiotic therapy within 14 days before the first dose of study drug.
* Life-threatening illness unrelated to cancer.
* Diarrhea that is greater than Grade 1 as outlined in the protocol
* Systemic antineoplastic or radiation therapy within 14 days or cytotoxic agents, or treatment with any investigational products within 21 days before the first dose of study treatment.
* Treatment with any investigational proteasome inhibitor.
* Systemic treatment with prohibited medications that are outlined in the protocol within 14 days of study treatment.
* Ongoing therapy with corticosteroids greater than 10mg of prednisone or its equivalent per day.
* Central nervous system involvement.
* Evidence of current uncontrolled cardiovascular conditions, including cardiac arrhythmias, congestive heart failure, angina, or myocardial infarction within the past 6 months.
* Known human immunodeficiency virus (HIV) positive, hepatitis B surface antigen-positive status, or known or suspected active hepatitis C infection.
* Serious medical or psychiatric illness that could, in the investigator's opinion, potentially interfere with the completion of treatment according to the protocol.
* Known gastrointestinal (GI) disease or GI procedure that could interfere with the oral absorption of tolerance of IXAZOMIB including difficulty swallowing.