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MDx/CDx Focus: FDA Okays PML Risk Test for Tysabri; MDxHealth Gets CLIA Nod; NY Approves AssurRx Lab


FDA Greenlights Quest's PML Risk Test for Patients Prescribed Tysabri

The US Food and Drug Administration has granted a de novo classification petition for Quest Diagnostics' Stratify JCV Antibody ELISA testing service for predicting the risk of progressive multifocal leukoencephalopathy, or PML, in patients receiving Tysabri.

PML is a rare but serious brain infection caused by the John Cunningham virus, or JCV. Although JCV is a common virus and generally harmless, people with weakened immune systems, such as patients using immunomodulatory therapies like Tysabri, have an increased chance of developing PML from the virus.

Tysabri (natalizumab) is used to treat multiple sclerosis and Crohn’s disease. It is marketed by Biogen Idec and Elan. The Stratify JCV Antibody ELISA test, which detects antibodies to JCV, is based on technology licensed from Biogen Idec, and is exclusively offered through Quest Diagnostics' Focus Diagnostics laboratory in the US.

FDA also updated the label for Tysabri to identify JCV antibody status as a PML risk factor. Other factors that increase the chance of Tysabri-treated patients developing PML include treatment with the drug for longer than two years, as well as treatment with immunosuppressants before receiving Tysabri.

FDA said in a statement that the risk of getting PML is greatest — around 11 out of 1,000 patients treated — if the patient has all of these risk factors.

The FDA reviewed data for the test through its de novo reclassification process, a regulatory pathway for low- to moderate-risk medical devices that are novel and not comparable to a device that is already on the market.

The agency noted that the Stratify JCV Antibody ELISA test should "not be used on its own as a basis for determining the risk for developing PML in patients on immunomodulatory therapy or for making clinical decisions." In addition, it noted that the test cannot be used to diagnose PML.

MDxHealth Gets CLIA Certification for Calif. Lab

MDxHealth said this week that it has received CLIA certification for its laboratory in Irvine, Calif.

The Liege, Belgium-based firm also said that the lab has passed inspection by the California Department of Health and is now "fully licensed and operational."

MDxHealth plans to offer through the lab a range of epigenetic diagnostic products for several cancer indications. It expects to commercialize its first assay, Prostate ConfirmMDx, in the first half of this year.

"Having our CLIA laboratory operational marks the beginning of our commercial activities in the US, a key driver to our long-term success," MDxHealth CEO Jan Groen said in a statement.

AssureRx Gets NY State Lab Certification

AssureRx Health said this week that its laboratory has been certified by the New York State Department of Health.

The state's approval means that the company's lab "is now certified to analyze DNA samples for pharmacogenomic testing in all 50 US states," the company said.

The certification also means that patients within New York State now have access to the company's GeneSightRx testing program through their personal prescribing clinician. GeneSightRx is a PGx test designed to help physicians determine which psychiatric drugs may be most effective for a patient.

Clinicians in New York State who wish to offer GeneSightRx need to register their practice with the company in order to begin testing. The company stressed that patients can only be tested with orders from "a properly licensed and registered clinician."