Medicaid is one of the largest — and most important — tools in the federal government’s arsenal to improve health equity. That’s why policymakers should be careful about making dramatic changes that could inadvertently decrease Medicaid beneficiaries’ access to care.

Medicaid is a lifesaving resource for vulnerable Americans. Multiple states have reported that after expanding Medicaid eligibility, they experienced an aggregate decrease in all-cause mortality rates. Even without expansion, Medicaid has long been associated with improved self-reported health status and decreased infant, child and adult mortality rates.

And the program’s reach is unrivaled. More than 85 million individuals are enrolled in Medicaid — that’s more than one in five Americans nationwide, four in 10 children, eight in 10 children in poverty, one in six adults, and almost half of adults in poverty. Relative to White children and adults, Medicaid covers a higher share of Black, Hispanic and American Indian children and adults. Medicaid also covers nearly a quarter of individuals under age 65 who live in rural areas, almost half of all births in most states, almost 65 percent of births nationwide among Black individuals, and more than 58 percent of Hispanic births across the United States.

Given how integral the program is to public health, it’s only natural for Americans — especially those from disadvantaged minority groups — to be skeptical of major policy changes like the ones that officials recently proposed to the Medicaid Drug Rebate Program (MDRP).

The MDRP was created to ensure that Medicaid gets the best price on prescription drugs. Currently, that “best price” is calculated as the lowest price available to any hospital, insurer, provider, health maintenance organization, nonprofit entity, or governmental entity in the United States.  

Officials are proposing a technical change to that methodology to define a drug’s “best price” as the aggregate sum of all discounts, rebates and price concessions offered for a unit of a drug, stacked on top of one another.

More savings for the government on prescription drugs might sound like an unalloyed good. But all policy decisions come with tradeoffs — and the proposal raises serious questions.

For instance, would the new best price rule reduce clinical and financial risk for Medicaid beneficiaries — who already face no or extremely low co-pays for prescriptions — or would it merely save the government money? And would those savings come at the cost of depressing investment in new and innovative treatments?

The rule’s potential deterrent effect on drug research must not be discounted, especially since Medicaid recipients have higher rates of disabilities and chronic conditions than other covered individuals in the public and private sectors. For example, nearly 40 percent of non-elderly Medicaid beneficiaries already live with a mental health condition.

Investment in psychiatric therapies has already fallen by as much as 70 percent in recent decades, with many manufacturers focusing on other more lucrative areas.  Will the proposed new method of calculating the “best price” exacerbate this downward trend — and harm those suffering from depression, schizophrenia, bipolar disorder and other mental health conditions?

Officials should proceed with a heightened degree of caution before changing the “best price” calculus. At the very least, officials ought to assess the likely clinical effect of the current and proposed approaches — and publish that information in formats and forums that are accessible and applicable to each state Medicaid program and its beneficiaries. Those assessments should be updated regularly, at least every five years.

Medicaid provides tens of millions of Americans with health services. The officials stewarding this vital program would be wise to remember one of the oldest medical principles — “first, do no harm.”