Sanofi Partners to Develop Diagnostic Test for Multiple Myeloma Patients on Potential Therapy

Sanofi announced that it partnered with Sebia to develop a new multiple myeloma diagnostic test that will help to mitigate the interference of isatuximab when measuring levels of monoclonal protein — a marker of disease severity — in a person’s blood.

Myeloma is a cancer of plasma cells, the type of cell responsible for making antibodies, or proteins that can specifically bind to a particular molecular target and are used to fight infection. When plasma cells become cancerous and grow out of control, they make an abnormal antibody, called monoclonal protein.

Because of this, measuring levels of this protein in the blood is critical for monitoring disease progression and response to therapy.

This is commonly done through immunofixation electrophoresis (IFE) tests, which detect antibodies based on how they move through gels in an electric field. Immunofixation is among the tests in the International Myeloma Working Group (IMWG) guidelines for diagnosing myeloma. Sebia, a diagnostic and monitoring company, makes a proprietary IFE test called Hydragel.

Isatuximab, being developed by Sanofi, is an investigational myeloma therapy under review by the U.S. Food and Drug Administration as a possible treatment of relapsed or refractory patients. A final decision is expected by April 30.

The therapy itself is an antibody, binding to a protein called CD38 with high specificity and selectivity. This is believed to induce myeloma cell death directly and through immune-mediated mechanisms.

Using antibodies for myeloma treatment, however, can alter the results of IFE tests. This interference can cause healthcare providers to misinterpret how well a person is responding to treatment.

The agreement covers the development of an Hydrashift 2/4 isatuximab in vitro diagnostic kit. This kit is intended to prevent isatuximab from wrongly affecting results in Sebia’s IFE tests. It will be specific for patients taking isatuximab as part of their treatment.

Per the terms of the agreement, Sebia will seek a CE (Conformitè Europëenne) Mark — a designation that a product conforms to certain regulatory standards in the European Union — by mid-year. It will then request clearance by the FDA.

Serbia already markets a similar product for Darzalex (daratumumab), a CD38-targeting antibody by Janssen Pharmaceuticals approved for several myeloma indications in the U.S. and Europe.

“We are excited about partnering with Sanofi and further developing our Immunofixation range of products,” Jean-Marc Chermette, chief executive officer of Sebia, said in a press release. “The future Hydrashift 2/4 isatuximab test is in line with our strategy of developing innovative and advanced products for patient care.”