The purpose of this study is to evaluate the pharmacokinetic (PK-the study of the way a drug enters and leaves the blood and tissues over time) characteristics of bortezomib when administered intravenously in Taiwanese participants with multiple myeloma (cancer of the types of cells normally found in bone marrow).

This is a Phase 4, single-arm, open-label (all knew the intervention of study), and multicenter (when more than 1 hospital or medical school team work on a medical research study) study to explore the pharmacokinetics with relapsed (the return of a medical problem) or refractory (not responding to treatment) multiple myeloma. The study consists of a Screening phase and a bortezomib treatment phase with defined PK sample collection time points. Participants will receive bortezomib intravenous injection two times a week up to 2 weeks (on Days 1, 4, 8, and 11) and followed by a 10-day resting phase (Days 12 to 21) for 1 treatment cycle. Pharmacokinetics will primarily be evaluated. Participants' safety will be monitored throughout the study.

Inclusion Criteria:

• Diagnosis of multiple myeloma based on the standard criteria
• Measurable, secretory multiple myeloma is defined as serum monoclonal immunoglobulin (Ig) G of >= 10 gram per liters (g/L), serum monoclonal IgA or IgE greater than or equal to (>=) 5 g/L, serum monoclonal IgD >= 0.5 g/L, or serum monoclonal IgM present (regardless of level), or urine M protein of >= 200 mg/24 hour at any time point of prior treatment
• Relapse or progression of myeloma following prior systemic antineoplastic therapy and meet the indication which had been approved in the drug leaflet. Relapse is defined as: a) reappearance of measurable disease (as defined above) following complete response (CR); b) >= 25 percent (%) increase in serum or urine M-protein according to IMWG (International Myeloma Working group) criteria; c) development of new or worsening lytic bone disease; d) new plasmacytomas or >=50% increase in the longest dimension of an existing plasmacytoma; e) worsening hypercalcemia (corrected serum calcium >11.5 milligram per deciliters [mg/dL-2.8 millimoles per liters [mmol/L] due to multiple myeloma
• Karnofsky performance status >=70%
• Platelet count >=50 × 10^9 /L without transfusion support within 7 days before the laboratory test

Exclusion Criteria:

• More than 3 previous lines of therapy (separate lines of therapy are defined as single or combination therapies that are either separated by disease progression or by a >6 month treatment-free interval)
• Peripheral neuropathy or neuropathic pain of National Cancer Institute-Common Terminology Criteria for Adverse Events (NCI CTCAE) Version 4.03 Grade >=2
• Any of the following within 3 weeks prior to enrollment in the study: antineoplastic or experimental therapy, corticosteroid use above 10 mg/day (prednisone or equivalent), or plasmapheresis
• Any of the following within 2 weeks prior to enrollment in the study: radiation therapy, major surgery (kyphoplasty is not considered major surgery)
• Prior malignancy other than multiple myeloma diagnosed or treated within the last 2 years, with the exception of completely resected carcinoma in situ or basal/squamous carcinoma of the skin](streamdown:incomplete-link)