As the landscape of Medicare Star Ratings continues to evolve, health plans face new challenges, and new opportunities.
In recent years, Medicare Advantage Prescription Drug plans have faced greater pressures in achieving higher Star Ratings due to elevated standards. In 2025, thresholds increased for many measures, including 5-Star cut points for adherence to diabetes, hypertension and cholesterol medications. Compared to 2022, there was a 35% decrease in plans achieving an overall 4-Star Rating or better.
With the 2026 Measurement Year on the horizon, now is a critical time for plans to evaluate how they approach quality improvement and healthcare outcomes. Pharmacy is an important lever that can help plans improve medication safety, increase adherence, elevate care and enhance clinical outcomes, ultimately impacting Star Ratings and revenue.
What’s Changing?
Over the next few years, several changes will go into effect that directly or indirectly impact measures related to medication safety and adherence. Preparing for these changes can help plans set the stage for success.
Experience and Access measures (2026 Star Ratings): The weighting of Patients’ Experience and Complaints Measures, and Measures Capturing Access, is decreasing from 4x to 2x beginning with the 2026 Star Ratings, which are based on data from the 2024 Measurement Year. This change in weighting reflects a strategic shift in placing greater importance on clinical outcomes and adherence-related measures in Star Ratings, which are tied to health improvement and cost reduction.
EHO4all (2027 Star Ratings): The Excellent Health Outcomes for All (EHO4all) program, formerly known as the Health Equity Index, incentivizes improved performance among certain groups of enrollees who are at risk for poor health outcomes. EHO4all will be implemented in the 2027 Star Ratings, which are based on 2025 performance data, and consider quality measures like those related to medication adherence.
MTM Program Completion Rate for CMR (2026 Display Measure): Although previously part of Star Ratings, CMS has moved the Medication Therapy Management (MTM) Program Completion Rate for Comprehensive Medication Review (CMR) measure to the Display Page for both the 2025 and 2026 Measurement Years. This measure is expected to return to the Star Ratings program in 2027, impacting the 2029 Star Ratings. The transition reflects CMS’s efforts to refine and refocus the measure set for greater impact, as CMS and the Pharmacy Quality Alliance (PQA) are exploring ways to evolve this into a more outcome-focused measure, but current data limitations prevent its elevation to Star Ratings. PQA is working on developing a Patient-Reported Outcome Measure (PROM) for CMRs, which could eventually support a Patient-Reported Outcome-Based Performance Measure (PRO-PM). Until such tools are validated and implemented, the CMR measure remains on the Display Page.
Additional PQA measures (2027 Star Ratings): CMS has finalized plans to include Polypharmacy: Use of Multiple Anticholinergic Medications in Older Adults (POLY-ACH) and Concurrent Use of Opioids and Benzodiazepines (COB) measures in the 2027 Star Ratings. They remain as Part D Display Measures for 2026. These measures address medication safety in older adults by evaluating medication combinations that heighten risk of medication-related harm. It’s important to note that the Polypharmacy: Use of Multiple Central Nervous System-Active Medications in Older Adults (POLY-CNS) measure is not included in the 2026 or 2027 Star Ratings. POLY-CNS remains on the Part D Display Page and has not been finalized for inclusion in Star Ratings.
Risk-adjusted adherence measures (2028 Star Ratings): CMS is retiring the current non-risk-adjusted adherence measures for diabetes, hypertension (RAS antagonists) and cholesterol (statins) medications, replacing them with risk-adjusted versions that consider factors like age. These risk-adjusted measures will be based on 2026 performance data, carrying a weight of 1x each in the composite Part D quality score, which is a decrease from the current 3x weighting. CMS transitioned to risk-adjusted adherence measures to improve fairness, accuracy and equity in evaluating health plan performance. Traditional adherence metrics did not account for patient-level factors like age, disability status or dual eligibility, which could disadvantage plans serving more complex populations.
Adherence and Outcomes
High adherence not only helps improve Star Ratings, which determine quality bonus payments and rebates, but it also lowers healthcare utilization and costs. One study found that missing just 1 adherence measure for diabetes medications, statins or RAS antagonists over a 3-year period was associated with 12% to 26% higher risk of all-cause and diabetes-related inpatient and ER stays, and patients who missed 4 or more adherence measures in that timeframe had 20% higher monthly medical costs.
In addition, according to the 2024 National Impact Assessment of CMS Quality Measures Report, from 2016 to 2020, 3.7 million more Medicare FFS and Medicare Advantage enrollees were adherent to statins, representing an estimated cost avoidance of $11.6 billion. Adherence to diabetes medications and RAS antagonists also improved for these populations.
In better controlling chronic conditions like cholesterol, diabetes and high blood pressure, it can also enhance overall health and quality of life, while impacting Part C intermediate outcomes.
Strategic Playbook for Approaching Pharmacy
Upcoming changes to CMS Star Ratings offer an opportunity for health plans to shift away from a transaction-based approach to pharmacy, which focuses on filling prescriptions, and consider how more advanced pharmacy care can enhance clinical and financial outcomes, helping ensure members adhere to the right medication regimens for better results. In leveraging a more proactive and comprehensive approach to pharmacy, plans should account for the following.
1. Remove structural barriers: Plans serving older populations or those at risk of poor health outcomes will now be evaluated with case mix taken into account. Removing structural barriers these populations might face like lack of transportation and limited health literacy through medication home delivery and one-on-one counseling can help improve adherence results.
2. Enhance access to quality care: Leveraging synchronized fills, medication reconciliation, day-and-time dose packaging and digital reminders paired with robust member engagement keeps members on track with their medication routines.
3. Monitor outcomes, not just fill rates: Track proportion of days covered and adherence metrics continuously, but link these with clinical indicators like blood pressure and A1C control to validate impact. In addition, monitor downstream utilization like ER and hospital stays along with cost trends to reinforce ROI and justify programs.
4. Align with CMS goals: Use predictive analytics to flag members who are at risk of medication-related problems or non-adherence early, including those facing challenges related to social determinants of health, and prioritize them for targeted interventions. Stratified reporting can help plans analyze risk and be tailored to specific goals, including Star Ratings.
Pharmacy remains a powerful lever for Star Ratings and is critical to overall clinical and financial outcomes. By leveraging data to intervene early, applying high-touch care and measuring real-world impacts, health plans can best position themselves to succeed in the changing landscape and take advantage of new opportunities. More advanced comprehensive pharmacy should be considered key for plans looking to optimize results.
