A Study Evaluating Venetoclax (ABT-199) in Multiple Myeloma Subjects Who Are Receiving Bortezomib and Dexamethasone as Standard Therapy

Inclusion Criteria:

• Eastern Cooperative Oncology Group (ECOG) performance score ≤ 2
• Participant has documented relapsed or progressive multiple myeloma on or after anyregimen or who are refractory to the most recent line of therapy. Relapsed myeloma isdefined as previously treated myeloma that progresses and requires initiation ofsalvage therapy, but does not meet the criteria for refractory myeloma. Refractorymyeloma is defined as disease that is nonresponsive (failure to achieve minimalresponse or development of progressive disease [PD]) while on primary or salvagetherapy, or progresses within 60 days of last therapy.
• Participant must have received prior treatment with at least one, but no more thanthree, prior lines of therapy for multiple myeloma. A line of therapy consists of ≥ 1complete cycle of a single agent, a regimen consisting of combination of severaldrugs, or a planned sequential therapy of various regimens.
• Prior treatment with bortezomib or other proteasome inhibitor is allowed, provided ALLof the following criteria are met: Disease is NOT refractory to any proteasomeinhibitor, defined as no disease progression (i.e., PD, per International MyelomaWorking Group [IMWG] or European Society for Blood and Marrow Transplantation [EBMT]criteria) while receiving proteasome inhibitor therapy or within 60 days after thelast dose, AND best response achieved with any proteasome inhibitor therapy (alone orin combination) was at least a Partial Response (PR), AND participant did notdiscontinue any proteasome inhibitor due to intolerance or ≥ Grade 3 related toxicity.
• Participant has measurable disease at Screening, defined as at least one of thefollowing: Serum M-protein ≥ 0.5 g/dL, OR Urine M-protein ≥ 200 mg in 24-hours, ORserum immunoglobulin free light chain (FLC) ≥ 10 mg/dL provided serum FLC ratio isabnormal.

Exclusion Criteria:

• Participant is refractory to any proteasome inhibitor, defined as progression on orwithin 60 days of the last dose of a proteasome inhibitor-containing regimen.
• Participant has had prior treatment with proteasome inhibitor within 60 days prior tofirst dose of study drug.
• Participant has any of the following conditions: Non-secretory multiple myeloma, active plasma cell leukemia i.e., either 20% of peripheralwhite blood cells or greater than 2.0 X 10^9/liter (L) circulating plasma cells by standarddifferential, Waldenstrom's macroglobulinemia, amyloidosis, POEMS syndrome (polyneuropathy,organomegaly, endocrinopathy, monoclonal protein, and skin changes), known HumanImmunodeficiency Viral (HIV) infection, active hepatitis B or C infection based on bloodscreen tests, significant cardiovascular disease, including uncontrolled angina, severe oruncontrolled arrhythmia, recent myocardial infarction within 6 months of randomization, orcongestive heart failure New York Heart Association (NYHA) Class ≥ 3, major surgery within 4 weeks prior to randomization, acute infections requiring parenteral therapy (antibiotic,antifungal, or antiviral) within 14 days prior to randomization, peripheral neuropathy ≥Grade 3 or ≥ Grade 2 with pain within 2 weeks prior to randomization, uncontrolled diabetesor uncontrolled hypertension within 14 days prior to randomization, any other medicalcondition that, in the opinion of the Investigator, would adversely affect theparticipant's participation in the study
• Participant has a history of other active malignancies, including myelodysplasticsyndrome (MDS), within the past 3 years prior to study entry, with the followingexceptions: Adequately treated in situ carcinoma of the cervix uteri or the breast,basal cell carcinoma of the skin or localized squamous cell carcinoma of the skin,prostate cancer Gleason grade 6 or lower AND with stable Prostate Specific Antigen (PSA) levels off treatment, previous malignancy with no evidence of disease confinedand surgically resected (or treated with other modalities) with curative intent andunlikely to impact survival during the duration of the study
• If participant had prior allogeneic stem cell transplant (SCT), participant hasevidence of ongoing graft-versus-host disease (GvHD)