Executive Summary

During May 2026, MARA issued 14 new rating actions across hepatology, oncology, neurology, immunology, psychiatry, infectious diseases, pediatrics, and gynecology. The distribution was concentrated in the middle reimbursement-risk bands, with 3 assets rated A, 8 assets rated B++, and 3 assets rated B+. 

The May distribution signals a portfolio pattern in which several assets demonstrate clinically relevant activity, but reimbursement strength remains constrained by comparator limitations, incomplete HRQoL evidence, uncertain cost-effectiveness, or reliance on surrogate and single-arm evidence packages.

The presence of three A ratings indicates that strong reimbursement probability remains achievable where clinical evidence, care-pathway integration, and economic defensibility are aligned. The larger B++ cluster reflects finely balanced reimbursement probability, where access remains plausible but sensitive to pricing, positioning, and HTA interpretation. The B+ ratings indicate lower reimbursement probability where evidence gaps are more pronounced.

Trigger and Structural Context

The May rating actions were issued as initial procedural updates to the MARA standardized reimbursement risk signal. These are not product announcements. They document structured reimbursement-risk assessments across drug–indication pairs using a consistent HTA-aligned framework.

The month’s evidence landscape was characterized by a recurring separation between clinical activity and reimbursement readiness. Several assets showed positive clinical signals in randomized or single-arm studies, but the strength of reimbursement probability was moderated by the absence of active comparators, limited patient-reported outcomes, incomplete economic modeling, or uncertainty around long-term outcomes.

This pattern is consistent with a core market-access principle: clinical success does not automatically translate into reimbursement strength. Under HTA scrutiny, evidence must support not only regulatory viability, but also comparative positioning, cost-utility anchoring, resource implications, and uncertainty management.

Domain-Level Drivers

Clinical Effectiveness was generally the strongest domain across the May ratings. Assets such as semaglutide in non-cirrhotic MASH with F2-F3 fibrosis, leniolisib in activated PI3K delta syndrome, and levodopa-carbidopa intestinal gel in advanced Parkinson disease demonstrated evidence packages sufficient to support A ratings. In these cases, clinical effect size, pathway relevance, and overall evidence coherence strengthened reimbursement probability.

Comparator Appropriateness was a recurring constraint. Several B++ and B+ ratings reflected evidence generated against placebo or single-arm benchmarks rather than active standard-of-care comparators. This was relevant for assets such as navepegritide, nadofaragene firadenovec, mavorixafor, and tovorafenib. This influences HTA interpretation because comparative positioning often becomes central to cost-effectiveness modeling, especially in established or emerging competitive classes.

Health-Related Quality of Life also limited rating strength across multiple assets. Where HRQoL data were absent, exploratory, non-utility based, or not statistically robust, the ability to support QALY-based modeling was reduced. This was particularly visible in several oncology, rare disease, and chronic therapy assessments. In HTA settings, lack of validated utility evidence increases dependence on assumptions and weakens cost-utility anchoring.

Cost-Effectiveness was one of the most important differentiators in May. Assets with defensible economic evidence or acceptable modeled value were more likely to reach the A band. By contrast, assets with no public cost-utility analysis, high ICER estimates, or uncertain price assumptions were concentrated in B++ or B+. This increases price corridor sensitivity and may affect negotiation leverage even where clinical evidence is positive.

Evidence Quality and Robustness also contributed to the middle-band concentration. Single-arm studies, small rare-disease trials, surrogate endpoints, immunobridging evidence, and incomplete long-term outcomes created residual uncertainty. These limitations do not preclude reimbursement, but they increase the probability that HTA bodies will require restrictions, managed entry arrangements, discounts, or additional evidence generation.

What the Ratings Mean

A++ to A
Strong probability of broad reimbursement under HTA scrutiny.

B++
Marginal. Reimbursement remains achievable but finely balanced and sensitive to pricing and positioning.

B+ to C
Lower probability of reimbursement with increasing risk of price pressure, restriction, delay, or rejection.

These are probability signals, not certainty statements. They reflect reimbursement probability under HTA frameworks, not regulatory viability.

Structural Implications for Stakeholders

For market access teams, the May ratings reinforce the importance of early evidence planning beyond efficacy endpoints. Assets with clinically relevant benefit may still face reimbursement friction where HRQoL evidence, active comparator data, or economic models are incomplete.

For portfolio prioritization and M&A diligence, the concentration in B++ is structurally important. B++ assets are not weak by default; they are finely balanced. Their reimbursement probability may change materially with pricing assumptions, comparator strategy, long-term evidence, or HTA-specific evidence requirements.

For forecast modeling, the May bulletin illustrates why internal forecasts can overestimate reimbursement success. A positive trial readout may support regulatory progress while leaving material uncertainty around cost-effectiveness, budget impact, and payer acceptance.

For pricing strategy, the ratings point to increasing sensitivity around value demonstration. Where evidence relies on surrogate endpoints, small samples, or indirect comparisons, launch price assumptions require external benchmarking. The Golden Question remains central: “If this pricing or launch decision is later challenged, what independent benchmark was relied upon?”

Methodological Integrity

The MARA framework is applied consistently across assets using a structured 10-domain assessment model. This ensures comparability across time and portfolios.

Ratings are calibrated to historical HTA outcomes and rely on publicly available evidence. Each assessment is reviewed using the same core domains, including Clinical Effectiveness, HRQoL, Cost-Effectiveness, Comparator Appropriateness, Evidence Quality and Robustness, Budget Impact, and Residual Uncertainty.

MARA operates under continuous surveillance. Ratings may be updated when material clinical, economic, regulatory, payer, or comparator developments emerge.

Monthly Ratings Issued

A: Semaglutide; Levodopa-Carbidopa Intestinal Gel; Leniolisib

B++: Relacorilant; Pegzilarginase-nbln; Zolgensma / onasemnogene abeparvovec; Yuviwel / navepegritide; Nadofaragene firadenovec; Xolremdi / mavorixafor; Lurbinectedin; mRNA-1083 / mCOMBRIAX

B+: Tovorafenib; BYSANTI / milsaperidone; FYLREVY / estetrol

MARA will continue to monitor material evidence events and adjust the reimbursement risk signal accordingly.

LinkedIn Post

Surveillance Update: MARA Monthly Ratings Bulletin — May 2026

In HTA-driven markets, evidence strength alone does not determine access. Comparative positioning, HRQoL evidence, economic defensibility, and uncertainty management often determine whether clinical activity translates into reimbursement probability.

During May 2026, MARA issued 14 new rating actions across multiple therapeutic areas.

A: 3 assets
B++: 8 assets
B+: 3 assets

The distribution was concentrated in B++ (Marginal), indicating that reimbursement remains achievable for many assets but finely balanced. Several May ratings reflected positive clinical signals moderated by placebo-controlled designs, single-arm evidence, limited HRQoL data, absence of public cost-effectiveness models, or sensitivity around price corridors.

The A-rated assets showed stronger alignment across clinical effectiveness, pathway integration, and economic defensibility. The B+ ratings reflected lower reimbursement probability where evidence gaps were more pronounced.

These actions reflect reimbursement probability under HTA frameworks, not regulatory viability.

MARA ratings are continuously monitored and updated when material evidence emerges.