More Than 20 States Now Mandate Coverage of Biomarker Testing

In April, New Jersey became the 21st state to sign into law legislation mandating coverage of biomarker testing for state-regulated plans. But gaps still exist in coverage: A recent Zitter Insights survey found that 30% of commercial and Medicare payers do not provide coverage of companion diagnostics — a type of biomarker testing — for their members.

On April 23, New Jersey Lieutenant Governor and Secretary of State Tahesha Way signed A-4163/S-3098 into law, mandating that state-regulated health insurance plans, Medicaid, the State Health Benefits Program and the School Employees’ Health Benefits Program cover “biomarker precision medical testing…for the purposes of diagnosis, treatment, appropriate management, or ongoing monitoring of a disease or condition, excluding asymptomatic screening, to guide treatment decisions of a subscriber when the test is supported by medical and scientific evidence.”

“We are continuing to advance our mission to make high-quality health care more affordable and accessible in New Jersey. By eliminating barriers to accessing biomarker testing, we are making it easier for families in our state to access personalized treatment plans,” said Way, acting as governor in the absence of Phil Murphy (D). “For someone battling life-altering and potentially fatal diseases like cancer, having this testing covered by insurance could make a world of difference in their treatment plan.”

Biomarkers are measurable indicators of biological processes and can be present in tissues, blood or other bodily fluids, providing information that helps providers diagnose, treat and monitor patients. They span everything from blood pressure to gene mutations and can identify subtypes of certain cancers, allowing providers to narrow down potential treatments to targeted therapies specifically approved for genetic mutations.

Biomarker testing benefits not only people with cancer; it is important in treating rare diseases, autoimmune disorders and Alzheimer’s.

As of mid-May, 16 states have passed a law mandating biomarker testing coverage for all state-regulated plans, five states have passed a narrow law, and 13 states have introduced legislation in 2025, according to the American Cancer Society Cancer Action Network (ACS CAN). Among the states with a narrow law, Arkansas, Colorado and Louisiana laws apply to state-regulated private plans, Florida’s law applies to Medicaid and the state employee health plan, and Connecticut’s law applies to Medicaid. Connecticut also is one of the states that has introduced legislation this year, as it seeks to broaden coverage to all state-regulated plans, including Medicaid, via HB 6771.

Companion diagnostics are a type of biomarker test that are used often in people with many cancers, including breast cancer, to identify the particular subtype they have, which guides oncologists to prescribe which of the many FDA-approved drugs would be most appropriate. For the Managed Care Oncology Index: Q1 2025, from Feb. 18, 2025, to Feb. 26, 2025, Zitter Insights polled 36 commercial payers covering 126.3 million lives, 27 Medicare payers covering 45.1 million lives and 50 oncologists about their coverage and prescribing of companion diagnostics for breast cancer.

AIS Health and Zitter Insights are both divisions of MMIT.

Almost three-quarters of all payers said they provide coverage of companion diagnostics for members needing treatment for breast cancer; about the same amount said their company requires test results for members before they can start treatment (see infographic).

Among respondents that said their company requires the results, 81% — payers with 67% of commercial lives and those with 95% of Medicare lives — said they require test results for specific breast cancer therapies only as opposed to all breast cancer therapies. And among those whose company covers companion diagnostics, 65% responded that their organization does not limit the number of times a patient can be tested for a specific mutation.

Among oncologists, 84% said they prescribe companion diagnostics. Sixty-four percent said payers require the test results for only certain breast cancer treatments, and 20% said they are required for all treatments, while 16% said those results are not required for breast cancer therapies.