By Kelly A. Briganti, Editorial Director, G2 Intelligence
Concerned that cancer patients may not receive “optimal care” when there are “multiple targeted therapy-companion diagnostic pairs,” the U.S. Food and Drug Administration (FDA), American Association for Cancer Research and the American Society of Clinical Oncology have planned a public workshop to engage in an “in-depth discussion of harmonization of companion diagnostic devices across a class of targeted therapies.” The workshop will be held March 24, 2015 in Washington D.C., in person and via an audiocast.
The goal of the discussion is to promote collaboration among entities involved in cancer research, facilitate “a deeper understanding” of cancer drug and device development, and utilize new scientific information to “harmonize companion diagnostics” for targeted cancer treatments.
The FDA’s notice of the workshop explains:
- Multiple manufacturers are developing therapeutic products that rely on a particular biomarker and that may require contemporaneous approval/clearance of a companion diagnostic if biomarker detection or measurement is necessary for the safe and effective use of the therapeutic product. Therapeutic product developers working in the same target space can use different methods and measures for the biomarker, and then partner with various sponsors to implement distinct companion diagnostics.
This can result in multiple approvals or clearances for treatment/companion diagnostic pairings within the same class of therapeutic products.
The FDA notice highlights the following issues related to a lack of harmonization:
> Using different companion diagnostics to test for the same biomarker within a drug class, using different antibodies or cut-off values, could result in “designation of different sets of marker-positive and marker-negative patients.”
> Manufacturers don’t compare results of different tests and “differences in results from distinct tests” aren’t evaluated for potential effect on efficacy.
> There’s “no assurance that all the tests identify the populations most likely to respond to all of the drugs;” so if different diagnostics are used for the same biomarker to determine treatment, problems can arise.
Finally, the FDA notice warns that “[u]sing multiple companion diagnostics to determine therapy for each patient is costly, inefficient, and challenging when dealing with a limited biological specimen” and at the very least can “lead to suboptimal use of the drugs.”
In addition to the live public workshop on March 24, the FDA is accepting written comments through April 23, 2015. For instructions on registration for the live workshop and submission of written comments, see the FDA notice in the March 9, 2015 Federal Register, pages 12498-99.