Federal drug pricing policy is evolving at an extraordinary pace. With implementation of the Inflation Reduction Act (IRA) well underway and the recent announcements of new Center for Medicare and Medicaid Innovation (CMMI) models — GUARD and BALANCE to name a few — plans, manufacturers, providers and patients are navigating a rapidly shifting landscape. The volume and pace of change can be challenging to navigate. Read on for key implications, particularly for the Part D market and the patients who depend on it.
A Fragile Baseline: Part D in Transition
The Part D benefit is already undergoing historic restructuring because of the IRA (e.g., significantly increased plan liability, new annual out-of-pocket maximums). These reforms materially alter financial risk across stakeholders and have introduced heightened actuarial uncertainty for plan sponsors.
Early market indicators suggest strain. Over the past two years, the stand-alone Prescription Drug Plan (PDP) market has experienced contraction, with fewer plan options, volatile premiums and market exits. At the same time, the therapeutic mix is shifting (e.g., rise and expansion of GLP-1 therapies).
This is the baseline against which the new CMMI models will operate.
The New Models and Part D Impact
Although GUARD and BALANCE differ in design, they share a stated objective: improving affordability for patients and reducing federal spending. Yet the policy tools deployed may have unintended consequences for access and market stability.
- Increasing Fragmentation Within the Benefit
Part D spending is increasingly flowing through mechanisms outside traditional plan management tools — whether through Maximum Fair Price (MFP) implementation, redesigned manufacturer discounts or model-specific payment adjustments.
As more financial flows are carved out or redirected, the portion of spending directly managed by plan sponsors shrinks. This raises important questions: How will plans manage spending trends if their flexibility over formulary design and utilization management is constrained? How will they account for risk in an environment where key cost drivers are partially externalized?
One potential consequence could be narrower formularies or more aggressive utilization management as plans seek to offset rising liability and uncertainty. While these strategies may be rational responses to risk, they can create friction for patients seeking timely access to therapy.
- Adverse Selection and GLP-1 Dynamics
High-demand therapies such as GLP-1s introduce additional complexity. Utilization of GLP-1 therapies — initially concentrated in diabetes — continues to grow, with expanding uptake in obesity and additional indications under evaluation. If the new models create different financial treatment or coverage of incentives across plans, adverse selection becomes a real possibility.
Plans perceived as more permissive in covering GLP-1s — or better positioned to absorb their costs — may attract a disproportionate share of patients seeking those therapies. Concentrated risk could drive premium increases, prompt benefit redesign or accelerate market exits.
At the same time, uncertainty around coverage criteria may complicate patient decision-making. For patients evaluating plan options during open enrollment, variability in formulary positioning, prior authorization requirements or utilization controls from year to year could undermine confidence in coverage stability.
- Affordability Goals and Access Realities
Each of the new models references affordability as a central objective. Yet affordability and access are not synonymous. Policies designed to reduce federal spending or redistribute liability can, if not carefully structured, introduce new access barriers.
Potential downstream effects for patients may include:
- Expanded prior authorization requirements
- Increased denial rates or step therapy protocols
- Therapy delays or abandonment
- Greater variability in coverage year over year
- Disproportionate impact on vulnerable populations
For patients managing chronic conditions, predictability is often as important as affordability. Frequent shifts in coverage or administrative requirements can erode trust and complicate care.
Implications for Stakeholders
In the near term, plans and manufacturers face immediate operational and strategic decisions, including model participation and formal comments (which were due February 23 for GUARD). These decisions must balance potential opportunities against the risk of market disruption.
Over the medium term, the interaction between IRA reforms and the CMMI models could create new structural fault lines within Part D. As financial responsibility shifts and new guardrails are introduced, the role of plan sponsors may evolve further — potentially narrowing opportunities for benefit differentiation.
Looking longer term, these policies will likely influence trends in benefit design and overall market competition. Most importantly, we will be watching to see whether patients experience greater clarity and stability — or increased complexity and limited access.
Looking Ahead
Layering multiple reforms onto an already transformed Part D benefit risks creating complexity rather than clarity. For patients, that could mean uncertainty: a therapy covered one year but restricted the next, shifting premiums and formularies that evolve faster than they can reasonably track.
For industry stakeholders, this moment calls for disciplined analysis, proactive engagement and a clear focus on the patient experience. As policy experimentation continues, success will depend on anticipating downstream effects and aligning policy strategy with long-term access goals.
The Reservoir team works at the intersection of health policy and communications to help clients navigate precisely this type of environment — where technical policy, access dynamics and patient impact converge. As GUARD, BALANCE and other CMMI models move toward implementation, thoughtful engagement will be essential to ensuring that affordability efforts translate into sustainable access for the patients that Part D was designed to serve.