Breaking Down the Latest OIG Work Plan Updates for April 2026

Some of the work plan items added to the OIG Work Plan in April 2026 are listed below. Compliance officers and auditors should review the recent announcements and adjust their compliance work plans and annual audit plans as necessary.

Medicare Payments for Laboratory Tests

Medicare is the largest payor of clinical laboratory services in the United States. As a result of the Protecting Access to Medicare Act of 2014 (PAMA), Medicare Part B changed the way they paid for lab tests. This change was effective starting in 2018. PAMA also requires the HHS OIG to publicly perform and release an annual analysis of the top 25 lab tests by expenditure. This work plan announcement explains the OIG will create, as required under PAMA, a data snapshot providing the analysis of the lab tests.

By way of example, the prior year’s report, published in January of 2026, is the analysis of the top 25 lab tests, by expenditure, for the calendar year 2024. This report gives readers insight into what they might expect in this recently announced work plan item. It can be found here: https://oig.hhs.gov/documents/evaluation/11453/OEI-09-25-00330.pdf

Some of the conclusions drawn by the OIG included:

• In 2024, Medicare Part B spending on clinical diagnostic laboratory tests (lab tests) totaled $8.4 billion—a 5-percent increase over the previous year. Spending on lab tests is climbing even as the number of Part B enrollees with lab tests is decreasing.
• Part B spending on lab tests has been shifting increasingly toward genetic tests, including tests related to cancer, infections, and epilepsy. In 2024, genetic tests accounted for 43 percent of all Part B lab spending, with expenditures topping $3.6 billion.
• Overall, Medicare Part B spending for non-genetic tests, including metabolic panels, lipid panels, and complete blood cell counts, has been generally declining since 2021, dropping to $4.8 billion in 2024.
• In 2024, the top 25 lab tests accounted for almost half of all Part B lab spending, with expenditures exceeding $4.1 billion. The test with the highest expenditures was a genetic test with a median payment amount of $447 per claim.

Series of Audits of Medicaid Laboratory Tests

OIG has announced another audit in their series of previously announced audits related to Medicaid laboratory tests.

Medicaid reimbursement for outpatient clinical diagnostic laboratory services performed in a physician’s office, by an independent laboratory, or by a hospital laboratory, generally may not exceed the amount set in the Medicare clinical laboratory fee schedule. The OIG’s objective with this audit is to determine whether selected States claimed Federal Medicaid reimbursement for outpatient clinical diagnostic laboratory services in accordance with the payment limits set in Federal and State requirements.

The public will not know which States are being audited and the audit report titles will remain unpublished until projects are complete and reports are posted. There are a total of eight projects announced in this series of audits with the following project titles and announcement dates:

• Project OAS-25-01-004 • Announced on Oct 15, 2024
• Project OAS-25-01-076 • Announced on Feb 18, 2025
• Project OAS-25-01-084 • Announced on Mar 10, 2025
• Project OAS-25-06-095 • Announced on Apr 28, 2025
• Project OAS-25-05-120 • Announced on Jun 26, 2025
• Project OAS-26-04-005 • Announced on Oct 6, 2025
• Project OAS-26-01-034 • Announced on Jan 13, 2026
• Project OAS-26-01-089 • Announced on Apr 14, 2026

Compounded GLP-1 Drugs

If you’ve seen commercials lately, you are likely to have watched at least one about the weight loss drugs called GLP-1 medications, such as Ozempic, Wegovy, Mounjaro, and Zepbound. GLP-1s are glucagon-like peptide-1 receptor agonists.

Recent large-scale compounding of these drugs has highlighted challenges the Food and Drug Administration (FDA) faces in overseeing the quality of these products and mitigating risks to patients. For a three-year period, certain GLP-1 drugs were on FDA’s drug shortage list, so compounding facilities were allowed to produce copies of these drugs. Even though the shortages ended in early 2025, some facilities may still be compounding large quantities of GLP-1 drugs.

The OIG plans to study FDA's efforts to oversee the compounding of GLP-1 drugs, including the extent to which FDA inspects compounders and leverages available data to identify and address potential risks.

NIH Grants

The National Institutes of Health (NIH) awards more grants than any other HHS Operating or Staffing Division. They fund billions of dollars each year, awarding grants directly to prime recipients, who can then make subawards to additional recipients (i.e., subrecipients).

The responsibility for overseeing subrecipients rests with the prime recipients as outlined in the NIH Grants Policy Statement and the Office of Management and Budget’s Uniform Guidance. For example, subrecipients are subject to the same fiscal and programmatic restrictions as the pass through entity, or primary recipient. This includes, but is not limited to, reimbursement of only costs that are allowable under the federal cost principles, beneficiary eligibility restrictions, and geographic scope restrictions, among other requirements. Because any improper expenditure of the subrecipient will constitute an unallowable cost for which the primary recipient, grantees should take the time to mitigate subaward risk by drafting clear and sufficiently robust subrecipient agreement terms.

In this evaluation, the OIG plans to determine the extent to which NIH prime recipients adhere to select requirements for oversight of domestic subrecipients. The hope is that this work will improve NIH prime recipients’ oversight of domestic subrecipients, resulting in reduced opportunities for fraud, waste, and abuse in domestic NIH subawards.

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