What is the sBCMA (serum BCMA) Test?*

BCMA (B-Cell Maturation Antigen) is a tumor necrosis factor receptor family member present on normal and malignant B-­cells that play a key role in immune function.

  • Elevated in cancers of B-­cells (multiple myeloma, chronic lymphocytic leukemia and Waldenstrom’s macroglobulinemia and some other malignancies)
  • Reduced in those with reduced B-­cells (immune deficiency syndromes)

The sBCMA test is a simple blood test to determine serum levels of this protein

  • Performed at least weekly during the first month of any new treatment and then monthly thereafter
  • Levels are independent of kidney function unlike other blood tests

sBCMA Test Benefits

  • More rapid and accurate ongoing assessment of treatments for multiple myeloma, chronic lymphocytic leukemia and Waldenstrom’s patients (days vs. months)
    • Avoid wasted time and unnecessary cost of ineffective therapies
    • Allow switching to treatments that will be effective
    • Help optimize dose and schedule of treatments
  • Predicts outcomes including both progression-­free and overall survival for patients
  • Provides a way to assess immune status of patients and develop risk adapted therapy for patients with
    • Solid tumors including breast cancer (low levels predict worse outcome)
    • Immune deficient states (low levels and related to complication rates)
  • Identify patients that require immediate treatment vs close follow up vs standard “wait and watch”
  • Assist in developing new treatment paradigms

sBCMA Use In Multiple Myeloma

A test is needed that is analytically stable and provides a much more rapid and accurate assessment of the disease status so that the doctor can immediately change from ineffective and costly therapy to one that may be beneficial.

  • Multiple myeloma is a constantly evolving incurable disease requiring many different therapies
  • Close monitoring for changes in response to these treatments is critical
  • 30,000 new patients/year; 150,000 patients in the US with the disease

sBCMA vs Current Diagnostic Tests


Current Tests

  • Accurate
  • Independent of kidney function
  • Biomarkers change quickly, allow for rapid assessment of response
  • Works in nearly all patients including “non-­secretors”
  • Useful for prognosis
  • Noninvasive blood test
    • Inexpensive
    • Accurately reflects the degree of involvement
    • Does not depend on the quality of specimen obtained
  • Often inaccurate
  • Altered in patients with impaired renal function
  • Biomarkers change slowly, does not help guide rapid changes in patient assessment
  • Do not work in many patients (“non-­secretors”)
  • Not useful for prognosis
  • Invasive bone marrow test
    • Expensive
    • Does not reflect the degree of involvement
    • Depends on quality of specimen obtained

Summary of Completed Studies

  • sBCMA test distinguished between active myeloma, smoldering myeloma, monoclonal gammopathy of undetermined significance (MGUS) and healthy donors
  • Baseline sBCMA predicted response to treatment
  • Changes in sBCMA more rapidly and accurately determined response to therapy for both improvement and worsening of disease
  • Predicted both progression-­free and overall survival
  • Enabled assessment of clinical status during treatment for “non-­secretors”
* The sBCMA test has not yet been cleared for clinical diagnostics use in any regulatory jurisdiction. For Research Use Only.