understanding serum free light chain (freelite®) and heavy chain-light chain (hevylite®) tests...

Understanding Serum Free Light Chain (Freelite®) and Heavy Chain-Light

Chain (Hevylite®) Tests

Judith A. Finlay Ph.D.Director of Scientific Affairs

The Binding Site, Inc.San Diego, CA

Some of the subject matter and data contained or addressed in the following presentation may involve off-label or forward-looking use of Freelite® kits, Hevylite® kits and other Binding Site products. As such, no off-label use of Freelite, Hevylite or other Binding Site products can be supported by Binding Site Inc.

Outline

• Background

• Tests used to Assess Multiple Myeloma

• Advantages of serum Free Light Chain Tests (Freelite®)

• Practical Considerations

• New Hevylite® tests

• Summary

Multiple Myeloma: a cancer of the Plasma Cells

• Cancerous plasma cells accumulate in the bone marrow and cause symptoms:– Increased Infections– Kidney Damage– Anemia– Bone Damage

• Use Testing to monitor disease and guide therapy

Plasma Cells are in the Bone Marrow

Red Blood Cells

White BloodCells (Blymphocytes/Plasma cells)

Platelets

Soft blood-forming tissue that fills the cavities of bone

Plasma Cells Produce Antibodies and Light Chains

Kappa Lambda

Antibodies are Made up of Heavy Chains and Light Chains

h

AntibodiesAntibodies

Heavy ChainsHeavy Chains

Light ChainsLight Chains

Normal vs Myeloma

Lots of different types of whole antibodies

Whole Ab and excess light chains – and too many of both!

Normal

Intact Ig Myeloma

IgG κIgG LIgA κIgA LIgD κIgD LIgE κIgE LIgM κIgM L

IgG κ

IgG κIgG LIgA κIgA LIgD κIgD LIgE κIgE LIgM κIgM L

IgG κ

THERAPY

KILLS MYELOMA CELLS

FEWER MYELOMA CELLS = FEWER

ANTIBODIES AND LIGHT CHAINS

Myeloma Therapy

There Are Two Types Of Free Light Chains – Kappa And Lambda

Kappa Free Kappa Free Light ChainsLight Chains

Lambda Free Lambda Free Light ChainsLight Chains

The FreeLite Test Measures Free Light Chains

Advantages of Freelite Tests

• Serum test specific for free light chains

• Very sensitive for detection of free light chains

• Early detection of response to treatment

• Earlier detection of relapse

Tests Measure Antibodies and Light Chains

AntibodiesAntibodies

Free Light ChainsFree Light ChainsPlasma CellPlasma Cell

Measured by SPEP and IFE

Measured by Serum free light chain test = Freelite

Advantages of Freelite Tests

• Serum test specific for free light chains

• Very sensitive for detection of free light chains

• Early detection of response to treatment

• Earlier detection of relapse

Normal Ranges for the Freelite tests

Units (mg/L)

Kappa: 3.3–19.4 mg/L

Lambda: 5.7–26.3 mg/L

k/l ratio:0.26–1.65

Units (mg/dL)

Kappa: 0.33–1.94 mg/dL

Lambda: 0.57–2.63 mg/dL

k/l ratio:0.26–1.65

Types of monoclonal proteins

What type of MM do you have?

• Type of MM depends on type of abnormal protein found in blood or urine

• IgG kappa, IgG lambda, IgA kappa, IgA lambda• Light chain only (kappa or lambda)• Non-secretory (low to no protein)• Involved light chain: one that is elevated:

– E.g. IgG kappa, it is kappa• Determined by a combination of laboratory tests:

– SPE– sIFE– Freelite

Why is your MM protein type important?

• If you have high levels of light chains you may be more prone to kidney damage

• If you are an IgA MM you will benefit most from the Hevylite test

• You will be able to tell if your MM protein type changes– E. g. Light chain escape can be detected

Advantages of the Freelite Tests

• Serum test specific for free light chains

• Very sensitive for detection of free light chains

• Early detection of response to treatment

• Earlier detection of relapse

Patient with IgG Kappa Multiple Myeloma

Adapted from: Mead et al. BJH 2004 126:348

Freelite Detects Response Freelite Detects Response Earlier than SPEPEarlier than SPEP

Advantages of the Freelite Tests

• Serum test specific for free light chains

• Very sensitive for detection of free light chains

• Early detection of response to treatment

• Earlier detection of relapse

+ + + + +

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Relapse: FLC levels start increasing 4 months before IFE becomes positive.

Adapted from: Mosbaurer et al. Haematologica 2007:92:275

Freelite detects relapse earlier than IFE

Monitoring Therapy with Serum Free Light Chains

Advantages of the Freelite Tests

• Serum test specific for free light chains

• Very sensitive for detection of free light chains

• Early detection of response to treatment

• Earlier detection of relapse

Lab Reports

Units are important!May

July = 385 mg/L

Practical Considerations for the Measurement of Serum Free Light

Chains

• Laboratory variability– Day to day variation in a lab– Normal lab to lab variation– Different chemistry instruments(Different kits for different instruments)

• Biologic variability

• Clinical changes are much greater

Changing Laboratories

If you change the laboratory where your serum free light chains are measured:

– If possible, obtain some of the last sample and run it along with the new sample

– or– Establish a new baseline for your serum free light chain

levels– May note of units lab reports (mg/L or mg/dL)

The change in your absolute sFLC level should not effect the clinical interpretation

Total Light Chain Assay“The total light chain assays are no longer used for diagnosis. Only FLC measurements have relevance” David Keren ASCP Press 2012

Binding Site’s New Hevylite™ Tests

• Cleared by FDA• In studies in the USA• Early in tests’ development

– We expect these tests to add value to Freelite– We expect these tests to be especially helpful in

IgA MM patients• Durie and IMF has mentioned Hevylite• 2013 Publications: Mayo Clinic, Austria, TBS-

UK• Myeloma Canada summary

When you measure IgA

• You are measuring

• IgAk +IgAl

• (IgA +IgA)

IgG, A and M assays measure IgGk and IgGl, etc., together

IgGk IgGL IgAk IgAL IgMk IgML

Now IgAk and IgAl can be measured independently with Hevylite®Why is this important?

What is HevyLite?

• Hevylite at test that measures the heavy and light chains together

• So what?• Can distinguish:

– IgA v. IgA – IgG v. IgG– IgM v. IgM

Additional Resources

• www.wikilite.com (web version of our “red book”)

• Google “Binding Site”• Email us  info@thebindingsite.com• Call The Binding site 800-633-4484

– We have CESs & DSAs across the US and Europe

• Understanding Serum Free Light Chain Assays (IMF booklet)

• IMF website (myeloma.org)

Summary

• Multiple Myeloma– cancer of the plasma cells– found in the bone marrow

• Plasma cells produce– Antibodies– free light chains

• Measure with lab tests– Including free light chain test (Freelite)– To monitor therapy

• Fewer light chains means fewer plasma cells

• New test for MM: Hevylite