FDA Eases Approval Path for Certain Cancer Companion Diagnostic Tests

The U.S. Food and Drug Administration has issued a final order moving certain laboratory tests used to help guide treatment with approved cancer drugs from Class III to Class II, changing the premarket pathway manufacturers must follow. The change, published in the Federal Register and effective September 16, 2026, moves in situ hybridization (ISH) test systems — tools used alongside approved cancer treatments — from the most stringent device regulatory category to a less burdensome one.

Certain Cancer Diagnostic Tests Move From Class III to Class II

According to the official FDA announcement, ISH test systems indicated for use with a corresponding approved oncology therapeutic product (identified by product codes NYQ, MVD, OWE, and PNK) were previously classified as Class III devices, the highest regulatory tier, which required manufacturers to obtain full premarket approval (PMA) before bringing the devices to market. Under the final order, these devices are now reclassified as Class II, which requires premarket notification — a process commonly known as a 510(k) submission — rather than the more extensive PMA process.

How These Tests Help Guide Cancer Treatment

In situ hybridization tests are laboratory diagnostic tools that detect specific genetic material in tissue samples. In the context of cancer care, they are used as companion diagnostics — meaning they help determine whether a particular approved cancer drug is appropriate for a specific patient. These types of tests are commonly used in oncology settings that serve older adults, including Medicare beneficiaries undergoing cancer treatment.

The FDA stated that along with the reclassification, it is establishing a new device classification regulation and specific “special controls” — additional requirements designed to ensure the safety and effectiveness of these devices under the lower classification tier. The agency indicated it relied on valid scientific evidence in making its determination, and noted that data from an additional premarket approval application and several supplements, which became available after an earlier proposed order, were consistent with prior findings and did not raise new safety or effectiveness concerns.

The reclassification applies to post-amendment devices — those not commercially distributed before May 28, 1976 — that had been automatically placed in Class III. By moving them to Class II with special controls, the FDA determined that the new regulatory framework provides a reasonable assurance of safety and effectiveness for their intended use.

New Classification Takes Effect September 16

The new classification takes effect September 16, 2026. Affected devices will be subject to Class II general and special controls and premarket notification requirements rather than the Class III premarket approval process.

For patients and caregivers, the practical impact of this regulatory change would depend on how individual manufacturers and healthcare providers respond to the new classification framework. Readers who have questions about specific cancer diagnostic tests or how this regulatory change may affect their care should consult their healthcare provider or contact the FDA directly for the most current information.

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Amanda Blankenship

Amanda Blankenship is Chief Editor at District Media, Inc., leading content strategy, quality assurance, and editorial operations across high-traffic personal finance sites like SavingAdvice.com and CleverDude.com. A Wingate University graduate with a BA in Communications (Journalism focus), she brings over a decade of experience in digital publishing, writing, and team leadership in the personal finance space.