FDA Issues Draft Guidance For Oncology Companion Diagnostics

The U.S. Food and Drug Administration (FDA) has issued a draft guidance, the aim of which is to make it easier to get class labeling on diagnostic tests for oncology therapeutic products.

In a statement, FDA Commissioner, Scott Gottlieb said one challenge they faced in developing and diagnostics, was the way those diagnostics were sometimes labeled. Changing the labeling could help target the delivery of cancer drugs.

Guidance simplifies life for clinicians

The FDA hopes the draft guidance will make it easier for providers to use the same test to help guide the use of a class of oncology therapeutic products, rather than one specific oncology therapeutic product within that class.

The FDA defines a companion diagnostic as an in vitro diagnostic device that provides information essential for the safe and effective use of a corresponding therapeutic product. It said that trials presently designed to support approval of a specific therapeutic product and a specific companion diagnostic have led to companion diagnostic labels that only refer to a specific therapeutic product or products.

Of concern to the FDA was that in some cases, specificity in labeling could potentially limit the broader use of a companion diagnostic that may be scientifically appropriate. In some cases, there are multiple companion diagnostics approved or cleared by the FDA to detect the same mutations in the same specimen type, the agency said.

Gottlieb said the FDA was concerned that “the situation is not optimal for patient care because a clinician may need to order a different companion diagnostic, obtain an additional biopsy from a patient or both, to have additional therapy treatment options.”

In that regard, Gottlieb said they were seeking sponsors to “pursue labeling a companion diagnostic to reference a specific group or class of oncology therapeutic products, when the evidence would support expanding the indication, for instance to include a specific group or class of therapeutic products, rather than specific products.”

With the draft guidance, manufacturers do not have to develop companion diagnostics with expanded indications from the bottom, but rather, they can expand versions of previously approved or cleared companion diagnostic tests for which the test’s sponsor submits a premarket approval, supplement or a new “510(k) application, as appropriate, to expand the labeling to broaden the indication for use with a specific group or class of oncology products in the same disease.”

Gottlieb said the draft guidance, which is titled “Developing and Labeling In vitro Companion Diagnostic Devices for a Specific Group or Class of Oncology Therapeutic Products Guidance for Industry”, was meant to promote better patient care and added to the FDA’s public health goals.

“We also recognize that there are commercial challenges for companion diagnostics. And so, we’re trying to help sponsors more efficiently meet the requirements to support broader labeling,” Gottlieb explained.

FDA recommends five considerations

The FDA recommended five considerations in the draft guidance. The first consideration is whether a specific group or class of oncology therapeutic products can be defined for which a companion diagnostic will identify an appropriate patient population for potential treatment.

The next consideration is whether there is a detailed understanding of the mechanism of action of the specific group or class of oncology therapeutic products being considered for use with the companion diagnostic and the interaction between the therapeutic products and the biomarkers, at the mutation level,as  detected by the companion diagnostic.

Other considerations were whether there was sufficient clinical experience with at least two therapeutic products for the same biomarker-informed indications and whether the analytical validity of the companion diagnostic has been demonstrated across the range of biomarkers that inform the indication.

The final consideration is whether clinical validity of the companion diagnostic has been demonstrated with the therapeutic products in the disease of interest.

The Regulatory Affairs Professionals Society website said an example of a labeling issue in precision oncology involved “the identification of epidermal growth factor receptor (EGFR) mutations in tumors of patients with non-small cell lung cancer as FDA-approved companion diagnostics that identify these mutations are only indicated for a subset of the five FDA-approved therapeutic products.”

The FDA invited interested parties to submit comments on the eight-page draft guidance by February 5, 2019 and these could be included in the final version of the guidance.