How an evidence-based formulary reduces pharmacy costs by 30% while improving member access
5 Minutes
Team Curative
Kassie Herbst, Sr. Director of Clinical Affairs, Pharmacy
Nov 5, 2025
Between 2013 and 2020, the cost of prescription drugs for health insurers and patients combined rose 97%.
There are a lot of reasons costs rise, but in this case, rebates are a big piece of the puzzle. Most large health insurance plans rely on pharmacy benefit managers (PBMs) for drug coverage, and PBMs profit from manufacturer rebates (the money that drug companies pay back to insurers) – not from helping members pay less for their prescription drugs.
This structure rewards higher-priced drugs, not better health outcomes.
It’s not great for cost control for anyone — it actually pushes the more expensive medicine to the front of the line because Pharmacy Benefit Managers (PBMs) are financially incentivized to hawk them.
Your health care plan’s formulary (list of prescription drugs covered by a health insurance plan) might have this issue.
Kassie Herbst, our Senior Director of Pharmacy Benefits, knows this is a serious problem, and she knows that when you cut the rebate talk and focus on outcomes, costs go down.
Herbst shares how she makes decisions about which medications to cover, focusing on what works best for patients’ health and saves everyone money.
Key takeaways:
Cutting rebates from the formulary conversation leads to better health and cost outcomes
A patient-focused system cuts pharmacy costs by 30% per person per month
Evidence comes first for building an effective formulary
The hidden cost of rebate-driven formularies
When Herbst looked at different pharmacy benefit structures, she realized that business incentives and members’ needs never lined up.
To take it a step further — she learned the industry was built on a flawed structure.
"It really boils down to incentive misalignment,” she says, “both internally with business models as well as externally with patients.”
What happens is that the middlemen make money from offering higher-cost medications, not because a certain medicine is effective. That’s why patients are getting brand-name drug prescriptions when there are cheaper, equally effective alternatives.
"When you're dealing with a structure that doesn't have the same incentives to really encourage members to use the most effective, lowest-cost medications, that's just hyperinflating spend for the industry as a whole,” she says.
That means higher premiums, confusing benefits and prior authorization processes for members, and employers absorbing millions in spend every month — when they don’t have to.
She points to Stelara as an example. These familiar brand names often dominate because of massive marketing budgets — not necessarily superior clinical performance. In the case of Stelara, and many other name-brand drugs, a biosimilar or generic version works just as well and costs 90% less.
So why does Stelara get the action? Because the formulary incentivizes Stelara, bringing the cost burdens to employers and members and passing rebate profits to middlemen.
At Curative, the evidence-based alternatives are prioritized, so members get the same outcome without paying for the brand markup.
Looking at evidence instead of rebates
Herbst had a thought: deprioritizing rebate considerations from formulary decisions could be a game-changer. It would mean savings with no change in care.
She was sure that making formulary decisions based on clinical evidence and real-world outcomes rather than potential rebates would be a slam dunk for both employers and their employees.
"We don't chase rebates, we don't play any of those games,” Herbst says. “Our formulary's evidence-based, focused on what guidelines recommend.”
The goal is to put patient outcomes first, and save at the same time. Members see the savings directly at the pharmacy counter rather than through hidden rebate flows.
Because Curative’s plan removes rebate distortion, over 90% of prescriptions are available at $0 copay, including insulin, cancer medications, and other specialty drugs. Members get the medicine they need without worrying about what’s “preferred” on a rebate-driven list.
Pull-quote: “When you're dealing with a structure that doesn't have incentives to really encourage members to use the most effective, lowest-cost medications, that's just hyperinflating spend for the industry as a whole.”
How Curative built an evidence-based formulary
Step 1: Assemble a multi-disciplinary clinical evaluation team
“It all begins with our clinical pharmacy team,” Herbst says.
Curative built a core team made up of clinical pharmacists and medical directors from relevant specialties, and brought in consultants for highly-specialized areas like oncology or cardiology, too.
Once the team was ready, it wasn't time to talk about costs. Care comes first.
Step 2: Gather evidence for each drug class
Next, they get all their resources and data together. That’s pulling from experts, looking at clinical and real-world evidence, considering safety issues, and more.
Curative used information from:
Published guidelines from organizations like the American Heart Association and American Diabetes Association
Institute for Clinical and Economic Review (ICER) cost-effectiveness analyses
Peer-reviewed scientific studies
The framework was complete.
Step 3: Analyze real-world member outcomes
Taking all that data into account, it was time to get up close and personal.
"At Curative, we'll dive into our data and ask, ‘What is our member's experience on this medication? Does this actually help them control their disease a little bit better? Does this help keep them out of the hospital?’" Herbst says.
They looked at member-specific metrics: hospitalization rates, disease control indicators, and medication adherence patterns, then lined up those numbers with the theories from the trials they noted.
Step 4: Implement with stakeholder education and continuous monitoring
A formulary isn’t “set it and forget it.”
“Once the decision is implemented, we then say, ‘OK, how is this going? How do our members feel? Do we need to make any changes?’" Herbst says.
Curative set up a system for educating providers about formulary changes and employer groups about the rationale behind your plan, and trained member services teams with regular refreshers and updates.
They also created a feedback loop so problem-solvers can connect directly with employees if any fixes are needed.
What Curative’s formulary changes look like
The numbers say it all: Curative’s seen reductions of over 30% in their per-member-per-month (PMPM) costs compared to the industry standard.
That's millions of dollars on a monthly basis.
And members got access to medication that used to be too expensive.
Over 90% of medications are covered under Curative’s $0 copay — including cancer medications, insulin, and specialty drugs.
That means better health. Herbst shares that when one member was finally able to get medicine that was too expensive before, “we were able to avoid a heart failure exacerbation and keep them out of the hospital.”
With cost barriers out of the way, hospitalizations went down, and disease management got better.
For employers, this transparency means more predictable pharmacy spend and fewer surprises. Curative’s evidence-based model aligns incentives so lower drug costs flow directly into lower premiums and healthier members.
No middlemen. No mystery. Just medications that work.
Take a look at Curative’s formulary.
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Table of Contents
The hidden cost of rebate-driven formularies
Looking at evidence instead of rebates
How Curative built an evidence-based formulary
What Curative’s formulary changes look like
