Binding Site’s novel laboratory blood assays for intact immunoglobulins, Hevylite®, have recently become the only automated immunoassay cleared by the FDA for monitoring IgA and IgG Multiple Myeloma patients.
Hevylite® measures the concentration of each immunoglobulin subtype i.e. IgGκ, IgGλ, IgAκ, IgAλ, IgMκ, IgMλ using a rapid, quantitative method. These measurements are used to produce immunoglobulin heavy/light chain ratios, e.g. IgGκ/IgGλ, similar to Free Light Chain κ/λ ratios when using Freelite®.
The assays can overcome issues with serum protein electrophoresis including problems due to co-migration (commonly seen in IgA myeloma patients) and inaccuracies due to low or high levels of monoclonal protein.
In addition, reports suggest these assays may aid in identifying residual disease and relapse in some patients. Uniquely, Hevylite® also gives information about the uninvolved heavy/light chain pair e.g. IgAλ in an IgAκ myeloma patient.
Hevylite® can help when results from serum protein electrophoresis (SPE) and immunofixation electrophoresis (IFE) are difficult to interpret; this includes problems due to co-migration of monoclonal bands, lower sensitivity/high variation at low levels of monoclonal protein (<10g/L) and non-linearity due to gel dye saturation.
In a number of publications, Hevylite® showed disease relapse in Multiple Myeloma patients some months before a monoclonal protein could be detected using SPE and IFE. Results indicate that it is the unique ability to measure suppression of the uninvolved Hevylite® pair which adds sensitivity to this assay both for relapse and in detecting residual disease.
These assays are also CE marked and currently in routine use in a number of countries. Hevylite® is being evaluated by many institutions worldwide and has been the subject of more than 20 papers and around 200 abstract and poster publications.
Hevylite® is also mentioned in prestigious guidelines published by the British Committee for Standards in Haematology. This reflects the increasing number of publications showing the benefits of Hevylite® in a laboratory and clinical setting.