Current policy
Every lung transplant candidate receives an individualized lung Composite Allocation Score (CAS). This score determines priority for receiving a lung transplant when donor lung(s) become available. The lung CAS is individual for each candidate and each organ offer. The lung CAS point values represent each of the factors used to match organ offers with transplant candidates (Exhibit 1). The people who have the highest number of points for that organ offer will have the highest priority.
In October 2025, the Health Resources and Services Administration’s (HRSA) preliminary analyses documented a rise in allocation out of OPTN sequence (AOOS) that correlates with the implementation of the lung continuous distribution policy in 2023. In response, the OPTN Board of Directors considered potential changes to lung allocation to promote policy compliance and reduce AOOS.
Note: Certain changes described in this proposal were previously implemented following emergency action by the OPTN Board of Directors and are currently in effect while the proposal proceeds through the formal policy process.
Supporting media
Exhibit 1. Current Lung Composite Allocation Score
| Attribute | Definition | % of Available Points |
|---|---|---|
| Waiting List Survival | Expected 1-year waiting list survival | 25 |
| Post-Transplant Outcomes | Expected 5-year post-transplant survival | 25 |
| Candidate Biology | Total of ABO, CPRA, and height points | 15 |
| ABO | Based on percentage of compatible donors by blood type | 5 |
| CPRA | Based on percentage of compatible donors by CPRA | 5 |
| Height | Based on percentage of compatible donors by height | 5 |
| Patient Access | Total of pediatric and prior living donor points | 25 |
| Pediatric | For candidates under 18 years old | 20 |
| Prior Living Donor | For candidates who donated any organ | 5 |
| Placement Efficiency | Total of travel and proximity efficiency points | 10 |
| Travel Efficiency | Based on impact of distance on costs of travel | 5 |
| Proximity Efficiency | Based on impact of distance on other efficiency (time, availability, etc.) | 5 |
Note. Total Score = Waiting List Survival + Post-Transplant Outcomes + Candidate Biology + Patient Access + Placement Efficiency
Acronyms. ABO=ABO blood group system, CPRA=Calculated Panel Reactive Antibody
Proposed changes
- Increasing the weight on placement efficiency from 10% to 15% of the overall score.
- Reducing the weight on all other parts of the score proportionally, including points assigned to pediatric candidates less than 12 years old for waitlist survival and post-transplant outcomes.
- Replacing the existing travel efficiency and proximity efficiency rating scales with a single placement efficiency rating scale to assign points to potential transplant recipients based on the nautical mile distance between the donor hospital and the transplant hospital.
- Lung CAS scores for all lung and heart-lung candidates on the waiting list will be updated to reflect the changes to the lung CAS (Exhibit 2).
- Approved exceptions will remain in effect based on the percentage of available points approved by the Lung Review Board, and the points assigned for each exception will be reduced proportionately to the adjusted goal weights.
Exhibit 2. Revised Lung Composite Allocation Score
| Attribute | Definition | % of Available Points |
|---|---|---|
| Waiting List Survival | Expected 1-year waiting list survival | 23.6111 |
| Post-Transplant Outcomes | Expected 5-year post-transplant survival | 23.6111 |
| Candidate Biology | Total of ABO, CPRA, and height points | 14.1666 |
| ABO | Based on percentage of compatible donors by blood type | 4.7222 |
| CPRA | Based on percentage of compatible donors by CPRA | 4.7222 |
| Height | Based on percentage of compatible donors by height | 4.7222 |
| Patient Access | Total of pediatric and prior living donor points | 23.6111 |
| Pediatric | For candidates under 18 years old | 18.8889 |
| Prior Living Donor | For candidates who donated any organ | 4.7222 |
| Placement Efficiency | Total of travel and proximity efficiency points | 15 |
Note. Total Score = Waiting List Survival + Post-Transplant Outcomes + Candidate Biology + Patient Access + Placement Efficiency
Acronyms. ABO=ABO blood group system, CPRA=Calculated Panel Reactive Antibody
Anticipated impact
- What it's expected to do
- Reduce median travel distance for lungs
- Reduce logistical complexity in lung allocation
- Improve policy compliance
- What it won’t do
- It will not completely alleviate AOOS.
Terms to know
- Allocation out of OPTN sequence (AOOS): An organ allocation event in which an organ is offered, accepted, and/or transplanted outside the established match sequence.
- Composite Allocation Score (CAS): This score determines priority for receiving a lung transplant when donor lung(s) become available.
- Calculated Panel Reactive Antibody (CPRA): A score (0–100%) indicating the percentage of potential donors a patient is immunologically incompatible with due to antibodies.
Read the full proposal (PDF - 354 KB)
Submit a Comment
I want to express my strong opposition the OPTN’s May 7, 2026 emergency amendment to the lung Composite Allocation Score (CAS), which increased the weight of geographic placement efficiency and strengthened distance-based scoring.
This amendment was implemented without adequate deliberation, public comment, or consensus, AND despite opposition from the OPTN Lung Transplantation Committee and concerns from the transplant community.
The amendment reverses the goals of the 2023 continuous distribution system, which was designed to reduce geographic disparities and prioritize medical urgency, expected benefit, and equity.
Moreover recent studies have provided data (Valapour and colleagues. 2026 CHEST) that demonstrate geographic disparities already existed before the amendment, with West Coast centers and some rural centers having much lower effective donor numbers for hard to match recipients- which means that patients in some regions of the country have to be sicker than in other regions of the country to access organs. This is in direct conflict with the OPTN’s own policy which states
“organs should be considered a national, rather than a local or regional, resource. That is, geographical priorities in the allocation of organs should be prohibited.”
Equally concerning is that the OPTN board presented no data to justify these changes and their decision come at the expense of patients lives.
I urge OPTN to revoke the amendment and require any future changes to placement-efficiency weighting to undergo full modeling, transparent impact analysis, and public comment before implementation.
Julia Klesney-Tait
Medical Director University of Iowa
As a double lung transplant patient I know that the old CAS system works. I was at the end stage of my IPF and would not be here to respond today. If I had been under the new criteria, I would have succumb to IPF.
Location: Oklahoma
Relationship to Lung Transplant: Caregiver and community member
Regarding the November 20, 2025 OPTN Board meeting vote to alter the Lung Transplant Continuous Allocation Score (CAS) points and ratios in order to address concerns about Allocation out of Sequence (AOOS).
I am writing to respectfully urge HRSA and the OPTN Board of Directors to reverse the decision made during the November 20, 2025 Board meeting to remove five points from categories describing a recipient's medical condition and reallocate them to the efficiency category. I ask that the Continuous Allocation Score (CAS) point allocation and weighting be restored to the levels that existed prior to the November 20, 2025 vote.
This issue is deeply personal to me. My mother has spent years battling pulmonary fibrosis, emphysema, and pulmonary hypertension. As her daughter, I have watched her world become progressively smaller as the simple act of breathing has become increasingly difficult. I've attended appointments, helped navigate transplant evaluations, and experienced the uncertainty that comes with knowing a donor organ may represent her only chance at more time with our family.
Because of that experience, I believe the transplant allocation system must always place the greatest emphasis on medical urgency and the likelihood of benefit to the patient. While operational efficiency is important, it should never come at the expense of ensuring that the sickest patients receive the highest priority. Every point within the CAS represents real people, real families, and real lives.
I am equally concerned about the process by which this policy change was adopted. Major changes to a lifesaving allocation system should be transparent, supported by strong clinical evidence, and informed through meaningful public engagement. It is troubling that this change proceeded without a prospective public comment period, without published clinical evidence demonstrating the necessity of using the emergency pathway, and despite the unanimous recommendation of the OPTN Lung Committee opposing the change. When those with the greatest clinical expertise raise concerns about increased waitlist mortality, those concerns deserve to be taken seriously before implementation rather than evaluated after patients may already be affected.
Additionally, I share the concerns expressed by the Lung Transplant Foundation in its April 13, 2026 letter to HRSA and the OPTN Board of Directors, signed by seventeen lung disease patient advocacy organizations. Those concerns include:
* The absence of a prospective public comment period before a significant policy change.
* The lack of clinical evidence supporting the emergency policy pathway.
* The decision to disregard the unanimous recommendation of the OPTN Lung Committee.
* The risk that reducing emphasis on medical urgency could increase waitlist mortality for the highest-risk patients.
* The shift away from comprehensive modeling before implementation toward identifying problems only after patients are impacted.
* The need to ensure that patients, caregivers, transplant recipients, and lung transplant experts remain central participants in every stage of policy development.
The organ transplant system exists because of an extraordinary gift from donor families. Those gifts deserve to be allocated through a process that is transparent, evidence-based, and centered first and foremost on saving the lives of those in greatest medical need. As someone whose family has lived through the uncertainty of advanced lung disease and transplant evaluation, I respectfully ask the Board to restore the previous CAS weighting while continuing to study solutions to Allocation Out of Sequence through a collaborative, evidence-driven process.
Thank you for your consideration and for your commitment to improving the nation's transplant system. I hope the HRSA and the OPTN Board of Directors will reverse the November 20, 2025 vote and restore the previous CAS point allocation and ratios.
Sincerely,
Megan Butler
Joseph Voss
State of Residence: Kansas
Relationship to Lung Transplant: Caregiver/Community Member
Regarding the November 20, 2025 OPTN Board meeting vote to alter the Lung Transplant Continuous Allocation Score (CAS) points and ratios in order to address concerns about Allocation out of Sequence (AOOS).
I am writing to express my strong desire for HRSA/OPTN Board to reverse the decision voted on during the November 20, 2025 Board meeting to remove five points from categories describing a recipient's medical condition and reallocating them to the efficiency category, returning the CAS point allocation and ratios to the pre November 20, 2025 vote levels.
This matters to me because as a pastor of over 50 years, I have witnessed many lives lengthened through the gift of organ transplants. Currently I have a congregant who has been waiting for two years for a lung transplant. She is becoming very discouraged and fears time is running out for her. Anything that delays the waiting time is a great concern to us.
Additionally, I share the concerns expressed by the Lung Transplant Foundation letter directed to HRSA and the OPTN Board of Directors, submitted via the Critical Comments and Directives Pathway on April 13, 2026, and signed on to by seventeen distinct lung disease patient advocacy organizations, identifying the following primary concern areas as reasons to oppose this change to the CAS:
- Bucking decades of protocol, no prospective public comment period occurred before this major policy change, and no clinical evidence was supplied justifying the use of the emergency pathway at the time of the vote.
- No clinical rationale was given for ignoring the recommendation of the Lung Committee, which unanimously opposed this change to the CAS, and no solutions were proposed to address the concern that initial modeling suggested that these changes would increase the waitlist mortality for high-risk individuals.
- The change in protocol from extensive modeling before policy changes are implemented to minimal modeling with an intention of catching problems after they occur will endanger lives unnecessarily.
- Patient voices and specialized lung transplant expert opinion should be centered at every stage of OPTN policy development, including the identification of problems, proposed solutions, and the implementation of new policy geared at addressing identified problems.
Thank you again for the opportunity to comment. I sincerely hope that, based on the consistent and unanimous dissent from lung transplant professionals, lung transplant candidates/recipients, and community members, HRSA and the OPTN Board of Directors will reverse the November 20, 2025 vote and restore the CAS to its previous point and ratio allocation.
Sincerely,
Joseph Voss
I want to express my strong opposition the OPTN’s May 7, 2026 emergency amendment to the lung Composite Allocation Score (CAS), which increased the weight of geographic placement efficiency and strengthened distance-based scoring.
This amendment was implemented without adequate deliberation, public comment, or consensus, AND despite opposition from the OPTN Lung Transplantation Committee and concerns from the transplant community.
The amendment reverses the goals of the 2023 continuous distribution system, which was designed to reduce geographic disparities and prioritize medical urgency, expected benefit, and equity.
Moreover recent studies have provided data (Valapour and colleagues. 2026 CHEST) that demonstrate geographic disparities already existed before the amendment, with West Coast centers and some rural centers having much lower effective donor numbers for hard to match recipients- which means that patients in some regions of the country have to be sicker than in other regions of the country to access organs. This is in direct conflict with the OPTN’s own policy which states
“organs should be considered a national, rather than a local or regional, resource. That is, geographical priorities in the allocation of organs should be prohibited.”
Equally concerning is that the OPTN board presented no data to justify these changes and their decision come at the expense of patients lives.
I urge OPTN to revoke the amendment and require any future changes to placement-efficiency weighting to undergo full modeling, transparent impact analysis, and public comment before implementation.