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Establish Continuous Distribution of Lungs

eye iconAt a glance

Current policy

The current system allocates lungs by placing candidates into categories that are arranged by priority. Sometimes a candidate’s category places them on the side of a hard boundary that would prevent them from appearing higher on the match run. Continuous Distribution is a proposed allocation system that considers multiple patient and donor attributes all at once with an overall score. This overall score includes medical urgency, patient outcomes, biological make-up, and other candidate factors and efficiency of organ placement.

Learn how it works

A closer look at the proposal

Presentation to the OPTN Patient Affairs Committee about how continuous distribution works


View presentation PDF link

Proposed changes

  • Remove current classification system and replace with a lung composite allocation score which is comprised of the following attributes:
    • Post-Transplant Outcomes, or how long a patient is expected to live after receiving a transplant
    • Medical Urgency, or how long a patient is expected to live without receiving a transplant
    • Biological Disadvantages, for patients who are medically harder to match which includes candidate blood type, sensitization, and height
    • Patient Access, for patients under the age of 18 and patients who are prior living donors
    • Placement efficiency, or the resources required to match, transport, and transplant an organ which includes both travel efficiency and proximity efficiency
  • Each attribute has a rating scale, which will determine how many points a candidate receives for each
  • Each attribute has a relative weight. The total weights add up to 100
  • These points combine into a total score for the candidate
  • With every organ offer, a candidate receives a new Composite Allocation Score (CAS), which is used to rank the candidates

Anticipated impact

  • What it's expected to do
    • Remove hard boundaries that prevent candidates from being prioritized higher on the match run
    • Reduce waitlist deaths
    • Decrease the number of lungs that are transported via airplane
    • Increase transplant opportunities for pediatric candidates
  • What it won't do
    • Change allocation of other single organ transplants


  • Attributes
  • Weight of attributes
  • Multi-organ allocation
  • Exception review process

Terms to know

  • Composite Allocation Score (CAS): The total number of points assigned to a candidate on the wait list, which would determine their rank on a match run.
  • Rating Scale: Method used to calculate number of points awarded to candidates for each attribute. For example, if everything else is equal, should a candidate with twice as much medical urgency as another receive twice as many points? Applying the rating scale to each candidate’s information and combining it with the weight of the attribute results in an overall composite score for prioritizing candidates.

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eye iconComments

Anonymous | 10/01/2021

The Data Advisory Committee appreciates the opportunity to provide feedback on the Lung Committee’s proposal Establish Continuous Distribution. The Committee overall supports the proposal as written and provides the following recommendations: (1) calculate the composite allocation score to 4 or 5 decimal places or to the number needed to ensure each value is unique when ordered; and (2) do not require the reporting of sensitization data due to concern with these patients being bypassed if there is no serum for crossmatching.

OPTN Histocompatibility Committee | 10/01/2021

The OPTN Histocompatibility Committee appreciated the opportunity to review this proposal, and is highly supportive of the inclusion of CPRA in lung allocation.

Transplant Families | 09/30/2021

Transplants Families thank you for the opportunity to share our opinions. We think that the proposal is a good one and we agree that this is a great start. We worried that the priority points for height, pediatric priority, and possibly other biological disadvantages overshadow the fact that LAS score doesn't work well with children under 12. The purpose of this proposal is to make sure that all people (children and adults) get the best possible chance at having an organ, which is a tall order. We know that children and adults have different needs when it comes to getting an organ. Given this, we applaud the Lung Allocation Committee for trying its best to be equitable and fair in this proposal.

Society for Transplant Social Workers | 09/30/2021

The Society for Transplant Social Workers (STSW) wants to thank the OPTN for their dedicated work on this thoughtful proposal of establishing the framework of continuous distribution for lung allocation. The STSW is appreciative for the opportunity to comment. We are supportive of the proposal and encourage further discussions, such as: How would the process work if a waitlist pediatric patient transitioned to adulthood? Given the weights assigned for a Composite Allocation Score, a comment was brought up regarding the possible ethical concerns of transplanting unvaccinated COVID-19 patients who tend to be younger in age and by this system would receive higher scores versus someone who is chronically managing a pulmonary illness and older in age. This would inadvertently put chronically managing patients a disadvantage with longer wait times. Again, we thank the OPTN for this opportunity as we continue to advocate and support our patients and families through this journey.

Penn Transplant Institute | 09/30/2021

Penn Lung Transplant Program and Penn Transplant Institute support the concepts included in this proposal for Continuous Distribution of Lungs. We agree that the survival goal of beyond the current 1-year post-transplant is a significant improvement. However, it is difficult to predict 5-year survival based on existing pre-transplant data. We strongly urge the OPTN to consider a 3-year post-transplant survival instead of 5-year post-transplant survival, which offers more reasonable alignment with the proposed pre-transplant predictive algorithm. In addition, 3-year post-transplant outcomes are better understood and reported publicly via SRTR modeling and analysis. Additionally, we advocate that data on ECMO bridge to transplant be incorporated into waitlist and post-transplant models. This data is already reported via the OPTN registry and is available to incorporate into the risk models to assess predictive outcomes in the setting of bridging techniques. The use of bridging techniques has greatly expanded in the last 10 years and better incorporating this into predictive algorithms will go a long way towards improving prediction. We also appreciate the additional consideration of the impact of sensitization on lung allocation in the updated system as well. This will hopefully impact the gender inequality present under the current allocation system, resulting in lower transplant rates among female patients who tend to be more highly sensitized. Guidance on how to account for differences in center specific classification of sensitization (MFI thresholds, laboratory techniques, epitope level differences) may be helpful in standardizing practices across centers. Finally, our program encourages the OPTN to reconsider how the proposed model prioritizes multi-organ patients for allocation, as utilization of the heart or lung score alone for heart-lung and lung-liver patients poses a disadvantage for many of these patients. The score discrepancy in multi-organ lung transplant patients frequently leads to extended pre and post-transplant hospitalization and high acuity at the time of transplant. Utilization of the heart score or lung score alone should be abandoned and re-introduced for consideration by performing an analysis of waitlist mortality, time to transplant, allocation status at time of transplant by organ, total hospital days and post-transplant morbidity and survival. Thank you for the opportunity to comment.

Cystic Fibrosis Foundation | 09/30/2021

September 30, 2021 Submitted electronically at: On behalf of the Cystic Fibrosis Foundation (CFF) and the below signed individuals of the CF Lung Transplant Consortium, we write in response to the OPTN/ UNOS Public Comment Proposal, Establish Continuous Distribution of Lungs. Background on Cystic Fibrosis and the Foundation Cystic fibrosis (CF) is a rare genetic disease that affects over 35,000 people in the United States. In people with CF, a defective gene causes a thick buildup of mucus in the lungs, pancreas and other organs. In the lungs, the mucus obstructs the airways and traps bacteria leading to infections, extensive lung damage and eventually, respiratory failure. Over 280 people with CF received transplants in 2018, the majority of which were lung transplants. However, some people with CF also may require liver or kidney transplants due to the disease. In order to address the needs of people with CF living with advanced lung disease, as well as those considering transplant, the CF Foundation launched the Lung Transplant Initiative in 2016. Through this initiative, the Foundation is working to improve and standardize the care received by people with CF for whom transplant is an option and to find solutions to barriers that may adversely impact the chance of a person with CF receiving a donor organ. Continuous Distribution Model We applaud OPTN/UNOS for this proposal focused on what matters most: the people on the waiting list. They deserve an allocation system that aspires to reduce waitlist mortality to zero, transplants the most medically urgent, minimizes the risk of post-transplant complications and provides the opportunity for long term survival for as many as possible, and does so in a resource efficient manner. The current classification system has hard boundaries that can create barriers for a candidate with higher medical urgency to receive an organ if they are farther from the donor than someone closer, with less medical urgency. Developing an allocation system that prioritizes the most appropriate recipient when an organ becomes available without substantially jeopardizing the viability of the organ or creating unacceptable barriers to getting the organ to the appropriate person is a challenging task. The new Composite Allocation Score (CAS) moves beyond the classification system of the Lung Allocation Score (LAS) and prioritizes accommodating individuals who are medically harder to match or have other special considerations. We believe the categories of attributes identified by OPTN/UNOS included in this proposal are appropriate. In particular, we are pleased to see that OPTN/UNOS has addressed issues for harder to match recipients, such as, blood type, and candidate stature. We appreciate the additional consideration of the impact of sensitization on lung allocation in the update system as well. This will hopefully impact the gender inequality present under the current allocation system with lower transplant rates among women, who tend to be more highly sensitized. Future guidance from the OPTN Histocompatibility Committee on how to account for differences in center specific classification of sensitization (MFI thresholds, laboratory techniques, epitope level differences) may be helpful in standardizing practices across centers. We appreciate that OPTN/UNOS will still allow for exception requests where additional points can be requested if a transplant center believes the score does not properly or fully reflect the candidate’s profile. This will ensure a candidate’s transplant team will be allowed to provide a more nuanced perspective on prioritization. As this new allocation model is implemented, we ask OPTN/UNOS to closely monitor data on the immediate effects for any strong signal of unintended consequences, particularly for prioritization of pediatric candidates, and adjust as appropriate. Two aspects of the proposal related to pediatric patients will warrant monitoring if the proposal is adopted without change: 1) As allocation will no longer be stratified by donor age, pediatric candidates will not have explicit priority for pediatric donor lungs in the new system. This is mitigated in large measure by the addition of pediatric access points and also by the points provided for smaller candidates. Nonetheless, TSAM modeling suggested a significant shift in the age of donors transplanted into adolescent recipients (from 73% in the current system to over 80% from adults in continuous distribution). Although the modeling suggested 41-46% of these adult donors would be from 18-34-year olds, because the post-transplant survival model includes donor age as a factor, the SRTR report suggested that donor age may contribute to the predicted increase in adolescent 2 year post-transplant mortality. Although the committee anticipates that transplant center behavior will mitigate this concern, if post-transplant mortality in the adolescent age group increases as predicted it will warrant revisiting this aspect of policy. 2) Pediatric candidates less than 12 years old will no longer have explicit priority for pediatric donors ahead of adolescent candidates within 1500 miles of the donor hospital. Although the points for pediatric access and recipient height will combine to rank these candidates ahead of the majority of adult candidates in most scenarios, the prioritization within the two pediatric age groups is less clearly defined. The Tableau tool provided by the Committee is somewhat reassuring, but as Priority 1 candidates in the 0-11 age group will have no ability to increase their composite score as their disease progresses, waiting list mortality for this age group will warrant close monitoring Geographical Prioritization Changes We are pleased to see that the new CAS allows for more dynamic flexibility in addressing the distance from a donor hospital, taking into consideration a continuous scale, rather than a categorical scale. This will result in less emphasis on the distance than the current LAS that prioritizes hard geographic boundaries and ultimately limits patient access. Post-Transplant Survival We are encouraged to see that OPTN/UNOS took our previous comments and the analytic hierarchy process (AHP) exercise into consideration when establishing that five-year survival be included in the continuous distribution model. The one-year survival measure currently accounted for through the LAS does not accurately reflect how beneficial a transplant is for any given patient. In fact, it is unlikely that people decide to undergo lung transplantation with the aim of only surviving for one year. The longer-term outcome of 5-year post-transplant survival will optimize the quality-adjusted life year (QALYs) and transplant benefit. Multi-Organ Allocation We are pleased to see the establishment of OPTN Multi Organ Transplant Committee in order to address future improvements to the allocation of multiple organs to one recipient. As other organs transition to a continuous distribution allocation model, we ask OPTN/UNOS to closely monitor the impact of the new integrated systems and provide a potential mitigation plan if the data demonstrates inappropriate allocation and prioritization. We look forward to partnering with OPTN/UNOS and provide feedback on the effects this system may have on lung allocation. Conclusion We believe the continuous distribution framework has the potential to best address the need to appropriately weigh meaningful factors in organ allocation as proposed, and we are pleased to see OPTN/UNOS moving forward with this model. As the CAS is implemented, we expect to see decreased regional variation in transplant rates and increased patient access across the country. We hope to see OPTN/UNOS continue to respond to data and make necessary changes in the future in order to get the most benefit out of the shift to continuous distribution. We are happy to serve as a resource and look forward to working alongside OPTN/UNOS in the future on this issue. Sincerely, Albert Faro, MD Vice President, Clinical Affairs Cystic Fibrosis Foundation CF Lung Transplant Consortium Members Luke Benvenuto, MD Assistant Professor of Medicine Center for Advanced Lung Disease and Transplantation Columbia University Medical Center Jason Christie, MD, MS Chief, Pulmonary, Allergy and Critical Care Division Penn Medicine Joshua M. Diamond, MD MSCE Associate Medical Director, Penn Lung Transplant Program Penn Medicine Dan Dilling, MD Medical Director, Lung Transplantation Loyola University Courtney Frankel, PT, MS Research Program Leader Duke University Medical Center Ramsey Hachem, MD Professor of Medicine, Lung Transplant Program Medical Director Washington University School of Medicine Matthew Hartwig, MD, MHS Associate Professor of Surgery with tenure Duke University Health System Christian Merlo, MD, MPH Associate Professor of Medicine and Epidemiology, Division of Pulmonary and Critical Care Johns Hopkins University School of Medicine Isabel Neuringer, MD Associate Medical Director, Lung Transplant Program and Adult Cystic Fibrosis Center Massachusetts General Hospital Jagadish Patil, MD Assistant Professor of Medicine Division of Pulmonary, Allergy, Critical Care, and Sleep Medicine Joe Pilewski, MD Associate Chief, Division of Pulmonary, Allergy & Critical Care Medicine University of Pittsburgh Medical Center Kathleen Ramos, MD, MSc Assistant Professor of Pulmonary, Critical Care, and Sleep Medicine University of Washington, Seattle Pablo Sanchez, MD, PhD, FACS Surgical Director, Lung Transplantation and ECMO University of Pittsburgh Pali Shah, MD Medical Director, Lung Transplant Johns Hopkins University School of Medicine Laurie Snyder, MD, MHS Associate Professor of Medicine, Pulmonary Allergy & Critical Care Medicine Duke University School of Medicine Stuart Sweet, MD, PhD Professor of Pediatrics, Division of Allergy, Immunology and Pulmonary Medicine Medical Director, Pediatric Lung Transplant Program Washington University School of Medicine in St. Louis Fanny Vlahos Cystic Fibrosis Lung Transplant Consortium Patient Representative Stephen Weight, MD Associate Professor of Medicine, Pulmonary and Critical Care UCLA Medical Center

View attachment from Cystic Fibrosis Foundation

Anonymous | 09/30/2021

The OPTN Heart Transplantation Committee appreciates the opportunity to comment on the Continuous Distribution of Lungs proposal. Committee members noted that the attributes included in the composite allocation score for lung may or may not be appropriate for other organs. A member expressed some concern over travel efficiency being weighted the same as candidate biology, but acknowledged the clarification that the quality of data for travel is not complete so the proposal is aiming to capture impacts of travel with the information available. A member suggested including cold ischemic time, however those data can be mixed. Another member noted that it may be unlikely that a pediatric candidate would accept adult donor lungs but it was clarified that age limits can still be entered for lung transplant candidates.

Anonymous | 09/30/2021

The Workforce on Surgical Treatment of End-Stage Cardiopulmonary Disease for the Society of Thoracic Surgeons welcomes the ongoing evolution of thoracic organ allocation to satisfy the essential elements of the final rule: best use of donated organs and equitable distribution free from geographic or socioeconomic factors. The current model leverages both pre transplant and post transplant survival estimates to create a lung allocation score, coupled with various hard boundaries including organ distance, donor:recipient blood type match, and donor age. The proposed model would incorporate 5 weighted elements including waitlist mortality, post transplant survival, biologic disadvantage score (incorporating PRA, challenging blood types and heights), patient access score (pediatric recipients, and patients with prior living donor transplants), and an efficiency score to account for organ distance. The purpose of this proposal is to eliminate hard boundaries which might negatively influence equitable distribution and best use of donor organs. The Society is supportive of a continuous distribution model but offers some caution regarding the existing proposal. The pre and post transplant mortality models are based upon historical data and may not adequately incorporate the current landscape of lung transplantation, including longer ischemic times from broader sharing, expanding use of ex vivo donor lung conditioning, donation after cardiac death, and the growing number of patients transplanted during the late phase of acute respiratory failure, such as seen from COVID-19. We recognize that this proposal intends to function as a living model. It is imperative that there is ample fluidity for model recalibration as conditions warrant. While simulation would suggest that the current approach will result in a greater number of organs used locally, patients at the highest urgency are likely to require even further travel distances, which will impact efficiency and potentially post transplant survival. While the unique needs of pediatric recipients are heavily weighted in this proposal, there isn’t a clear mechanism to address transition to adulthood while on the wait list. We applaud the Lung Allocation Committee within the Organ Procurement and Transplant Network for their work on this proposal and look forward to ongoing evolution and collaboration.

Anonymous | 09/30/2021

The Ethics Committee appreciates the work of the Lung Transplantation Committee in developing this policy and for the opportunity to comment on it. A primary concern of the Ethics Committee is the limitations of historic modeling to predict future outcomes in a way that balances ethical principles. Specifically, there was concern that the recruitment and engagement resulted in participants who were already involved in the OPTN. Thus, it does not fully capture the voices of those whom are underserved and unable to access transplant making it an inaccurate representation of the transplant community. There was also concern about how the modeling and post-implementation monitoring plan can appropriately account for existing health disparities and increase equity and access for marginalized populations. The Ethics Committee encourages the Lung Committee to revise the post-implementation monitoring plan to review outcomes by demographics to gain a better understanding of how this allocation framework will affect specific populations. A member suggested that instead of weighting wait list survival and post-transplant outcomes as 25% each, the Committee could combine the two attributes to equalize life years. A few member expressed concern about the potential for gaming the system and trying to make themselves more attractive as candidates. Ultimately, the Committee feels like it is important to have a balance of utility and equity when developing an allocation framework.

Judy Brown | 09/30/2021

Cannot offer an opinion due to the complexity of the presentation. Please see attached document. General comment – the video presentation was a very quick read in that a lot of medical/technical coverage was provided in rapid succession. For the non-medically trained transplant candidate, a breakdown of acronyms would be helpful. Provide greater clarity when presenting if for non-medical audience. Comments are from the presentation slides in the file identified above. Given the Purpose of Proposal - Move from classification groups with hard boundaries to considering individual candidates holistically How and to what level do you separate subjectivity from objectivity? Provide explanation of Candidate Biology ABO and CPRA. Is the % of Available points for Post-Transplant Outcome at 25 if the expectation of the post-op survival period is “expected” to be at 5 years or longer. Is there some sort of sliding scale to 25 max? Example Match Runs do not contain the basis of the values provided. Is there directly proportional scaling for the listed attributes – such that comparing the 4 candidates (A, B, C and D) can be directly gaged? How much does subjectivity affect the values provided? If someone has already waited a year or more (Waiting List Survival) how does this translate from the existing process to the new process? Would they receive a max scoring? Will there be a transition of scoring for current candidates? In the “Rationale” - Extended from 1-year to 5-year post-transplant outcomes measure … how is this gaged prior to a transplant to establish the CAS? How does this “unknown” factor into the CAS scoring? Overall, due to the complexity of the information and failure to be presented in a manner comprehensible to non-medical individuals these questions were generated and need clarification in order to generate an individual’s opinion/input to the proposal.

View attachment from Judy Brown

Anonymous | 09/30/2021

All transplant teams are equal. How does this factor in i.e. should teams with better outcomes have higher priority? Should transplant teams/organizations be incentivized to do more to promote lung/organ donations/education? Those who do a better job would have "first choice" on available donations.

Anonymous | 09/30/2021

Region 11 sentiment: 3 strongly support, 10 support, 5 neutral/abstain, 0 oppose, 0 strongly oppose Comments: Region 11 supported this proposal and one attendee commented that it would be interesting and more transparent to show what factors made up candidates score on each match, rather than just showing a numerical score.

Anonymous | 09/30/2021

The Ad Hoc Disease Transmission Advisory Committee (DTAC) appreciates the opportunity to provide feedback on this proposal and overall supports the proposed changes. DTAC members identified that continuous distribution changes could impact travel patterns for organ distribution and it is important to consider that transplant centers in certain parts of the country may be less familiar with diseases endemic to other parts of the country, such as Strongyloides. The Lung Committee should consider in implementing this proposal providing education or guidance on screening of donors to minimize communication issues about test results for areas with differences in endemic testing.

American Society of Transplant Surgeons | 09/30/2021

The American Society of Transplant Surgeons (ASTS) supports the OPTN policy proposal with the following response to the OPTN Lung Transplantation Committee’s request for feedback. 1. Are the weights on each attribute ideal? Yes. See remaining data requested in the following comment (see bold or last 3 sentences under 1.a.). a. Should waitlist survival and post-transplant outcomes be equally weighted, or should waitlist survival receive twice as much weight as post-transplant outcomes? Currently the weighting is 2:1, waitlist mortality and post-transplant survival respectively. This is likely a function of not including post-transplant survival, but rather, transplant benefit in the post-transplant model that includes both waitlist mortality and transplant survival. Therefore, overall waitlist mortality is counted twice. According to the proposed models using TSAM calculations, it appears that the overall optimal combination is to weigh waitlist survival and post-transplant survival equally. This seems reasonable and aligns with community sentiment from recent surveys. What is not discussed in this specific request for feedback is what duration of post-transplant survival should be included in the model. We do not recall seeing data on the impact of the duration of post-transplant survival on the various outcomes measure to be reported by the OPTN; and importantly, we have concerns in the predictive capabilities for SRTR modeling past 3 years. These should be provided for the community to review. b. Is 10% the correct weight for efficiency (5% each for travel efficiency and proximity efficiency)? Based on the estimates provided by the OPTN, this seems to be a reasonable weighting as it appears to increase emphasis on truly local donors to be prioritized towards teams that would not require air travel while modestly increasing average air travel distances when that is required. 2. Are changes to exceptions appropriate? Yes. a. Is 5 days sufficient time to allow reviewers to vote on exception applications? These are timely requests and should be processed within 5 days. b. Is there a need to allow centers to list a candidate at an exception score while awaiting a decision on appeal after an initial denial? No, we do not believe that centers should be listing candidates at exception scores while awaiting a decision on appeal after initial denial. That practice introduces a level of subjectivism and practice variability that may be harmful to the overall allocation system. 3. Are the changes to multi-organ allocation appropriate? Yes at this juncture. a. Is the composite allocation score of 28 the right cut-off? It is not possible to understand how the changes will impact multi-organ allocation, nor do we have enough insight to make accurate predictions. However, the logic behind selecting 28 as a cut-off seems appropriate. This will obviously be a stop-gap measure as all the organs undergo alterations in their allocation based on the theory of continuous distribution. Unfortunately, that process will take years to mature. b. Does the proposal need to be adjusted to allow OPOs more discretion to offer from the heart list before offering the heart to candidates in need on the lung list who have a composite allocation score of at least 28? The proposal should not be adjusted to allow OPO’s more discretion at this juncture, but rather the impact should be closely monitored after implementation and real-time decisions and modifications able to be made by the Thoracic Committee and Executive Committee of the OPTN. 4. How many decimal places are useful for inclusion in reference numbers and equations? Two

Anonymous | 09/30/2021

The OPTN Liver and Intestinal Organ Transplantation Committee appreciates the opportunity to provide feedback on the Lung Committee’s proposal to establish continuous distribution for lungs. The Liver Committee supports the proposed changes to multi-organ allocation and does not have any specific feedback.

Anonymous | 09/30/2021

The Minority Affairs Committee appreciates the opportunity to provide feedback on Establish Continuous Distribution of Lungs from the Lung Transplantation Committee and provides the following comments: A member expressed their support for the proposed additional weight to post- transplant outcomes and the monitoring plan to ensure that policy changes are having their intended impacts. A member commented that the proposed 5 days is sufficient time to allow reviewers to vote on exception applications.

UNC Center For Transplant Care | 09/30/2021

I appreciate the hard work the committee has done on this difficult task. The attributes selected and weights assigned for a Composite Allocation Score seem like a good place to start. I think this approach will be fairer to patients awaiting lung transplant than using the hard and arbitrary geographic boundaries of the DSAs and even the current 250 nautical mile radius. I’m sure tweaks will be needed as we learn about how this new system works, but kudos for coming up with a score that has taken so many factors and public comment into account!

Anonymous | 09/30/2021

The Patient Affairs Committee (PAC) appreciates the work of the Lung Transplantation Committee in developing this proposal and for the opportunity to comment on it. The PAC was grateful for patient involvement in the AHP exercise and satisfied with the weights associated with each attribute of the CAS. The Committee does note that the implementation of this framework will require a heavy emphasis on patient and community education. It will be important for patients to gain a solid understanding of their CAS in order to maintain transparency and patient autonomy. The Committee asked to see the actual results of this change at one year so that they may compare it to the modeling that was done. The PAC recognizes the difficulty associated with redeveloping the allocation framework and thanks the Lung Committee for its attention to detail and vigor that was put into this endeavor. Overall, the PAC is supportive of the Lung Committee’s policy proposal and is appreciative of the opportunity to provide the unique patient perspective.

David Culver | 09/29/2021

Thank you for the opportunity to comment. I am alive today after receiving 1 lung to replace two diseased lungs at the end of 7 years with IPF. 1 lung was determined the best path to meet accepted surgical risk based on recent heart surgery. I am now 15 months out from the surgery and function on my own at the age of 66. I also have no issue with my heart as of this writing. My concern is the use of pipeline mgmt techniques ( lungs) in such a critical surgical process. If you standardize process and scoring to achieve numeric outcomes you will experience demographic desperate impacts. I believe I and others like me would fall into that gap. Decisions should always be left at those levels closest to the patient, by the doctors and staff. I have complete confidence in the team at UCSF to faithfully complete the processes for the good of the patient and in honor of the cost from the donor and family.

NATCO | 09/29/2021

NATCO would like to thank the OPTN on the ongoing assessment of continuous distribution of lungs, and are in support of the proposal. The CAS score has been defined appropriately to transplant the sickest patients, closest to the donor hospital. When speaking of the CAS score, we do believe that more weight should be given to the waitlist mortality group as opposed to the 5-year survival group at a ratio of 2:1. Waitlist mortality is easily quantified, yet the 5-year survival may be more difficult and not necessarily accurate. As this is rolled out, the 5-year survival may need to be adjusted to more accurately predict survival rates. The travel percentage of 10% is reasonable, and again this will need to be monitored to identify that travel is less rather than more. Continued education should continue, and patients/family members should be provided education through standard UNOS notifications as well as ongoing webinars. Certain risks to the proposed change may be those individuals who have an LAS score 40-50 having increased waitlist mortality. Close attention to this group needs to occur to avoid disparities. It will also be important to monitor the proposed outcome to the current state; if data is what was expected. Exception reviews should be completed in a timely manner, and we support the 5 day turn around. We also support patients being listed at an exception score while an appeal is pending. These patients are sick and further information may need to be provided to validate the exception. When it comes to offering organs off the lung match, we are also in support of this and the current proposal of a CAS of 28 for all organs is appropriate. Again, ongoing assessment will need to be done to assure that the scores are reflective for the organs respectively; heart, kidney and liver.

Anonymous | 09/29/2021

The Kidney Transplantation Committee appreciates the opportunity to comment on the Continuous Distribution of Lungs proposal. Committee members expressed support for including sensitization in the proposed allocation scheme, and suggested increasing the weighting of both sensitization and height attributes within candidate biology. One committee member commented that highly sensitized patients generally have much lower access, and the interaction of high sensitization and short height could be additionally disadvantageous. The member further expressed that size matching should be emphasized, particularly for women and shorter candidates. Committee members also expressed concern that the prior living donor attribute is weighted too low. One committee member commented that the rarity of prior living donor lung candidates should not influence the level of priority given to those candidates. Another committee member pointed out the kidney allocation scheme currently honors living donors of any organ and they are ranked highly in kidney allocation classifications. Additionally, a committee member recommended using modelling to better understand how a living donor, who now needs a lung, falls into the allocation scheme. Committee members expressed support for the multi-organ allocation scheme for lung multi-organ candidates.

Society for Pediatric Liver Transplantation | 09/29/2021

The Society for Pediatric Liver Transplantation strongly supports this proposal. We appreciate that the proposed weighting of each attribute in the lung composite allocation score closely aligns with the weights suggested by the community of all stakeholders in the AHP prioritization exercise. This reflects the larger community’s opinions about how to weight these attributes and is less swayed by any specific interest groups. We agree that it is important to include both age and post-transplant outcomes as attributes in a Composite Allocation Score. We hope that these general principles established in the Lung Continuous Distribution plan will be held consistently as guiding principles for Continuous Distribution plans across all solid organs.

Transplant Coordinators Committee | 09/29/2021

The Transplant Coordinators Committee (TCC) appreciates the work of the Lung Transplantation Committee in developing this document and for the opportunity to comment on it. A member suggested implementing a sliding scale for pediatric candidates since there are no biological differences between a 17 and 18-year-old patient. The TCC is supportive of reducing review board times. A member commented that it is challenging to accurately predict post-transplant outcomes so perhaps that weighting should be adjusted. A member noted that it is difficult to answer, as a community, what each attribute weighs and ultimately determine the balance between equity and utility in organ allocation. In terms of multi-organ transplant, a member stated that organ procurement organizations (OPOs) would rather have more clear-cut directions of how to allocate than the discretion to determine how. A member noted that lungs tend to drive care more than hearts so it is interesting that the heart match run will be completed before the lungs. Overall, the TCC is supportive of developing a continuous distribution framework for lung allocation and is appreciative of the opportunity to provide the transplant coordinator perspective.

Association of Organ Procurement Organizations | 09/29/2021

AOPO congratulates the Lung Committee on its work and development of this groundbreaking proposal to implement continuous distribution for the allocation of lungs. As stated in its previous comment to the concept document, AOPO views the continuous distribution framework as an effective way to incorporate and balance multiple medical and efficiency-based factors in a patient-focused manner. Continuous distribution will also provide future flexibility by allowing the OPTN to be more nimble in its ability to adjust and change the relative weighting of attributes over time as conditions for organ distribution evolve. AOPO will focus its response on the following questions posed by the Committee. o Should waitlist survival and post-transplant outcomes be equally weighted, or should waitlist survival receive twice as much weight as post-transplant outcomes? AOPO supports the proposal’s assignment of a one-to-one weighting for waitlist and post-transplant survival. As reported by the Committee, this weighting maximizes both patient survival on the waitlist and survival post-transplant. AOPO believes this outcome, aligned with maximizing the ethical principle of utility, should be imperative in lung allocation. The allocation system should be designed in a manner that clearly reflects good stewardship. From the OPO’s perspective, one of the most important outcomes for donor families is for gifted organs to save lives. The proposed weighting prioritizes this outcome – lives saved – to the extent the data modelling is predictively accurate. This is an analysis that should be reviewed critically post -implementation and adjusted if needed. Importantly, we recognize that these two attributes are assigned 50% of the total available points in the composite allocation score (CAS). As a result, equity and efficiency factors are combined with this utility calculation to support a balanced allocation framework. o Is 10% the correct weight for efficiency with a 1 to 1 on travel and proximity? AOPO agrees with the proposal’s incorporation of efficiency attributes to ensure “smarter” distribution by distributing organs over further distances with increased costs and lower efficiencies only for significant clinical differences. Specifically, AOPO supports the travel efficiency measure with assignment of maximum points for travel within 45nm and a steep decline thereafter where travel of lungs will likely be by air. The proximity factors use the same inflection point (45nm) but a different shape curve recognizing that efficiency gains are modest at a point once flights are involved until very significant distances/time is involved. However, AOPO urges the Committee to consider whether both travel and proximity are needed in the CAS. Because the travel score, although designed to be a proxy for costs, is directly tied to distance, proximity is already factored into the travel attribute. The travel and proximity curves are most notably different at long distances (over 1000nm) and are very similar at 0-90nm. Travel time, if and when it could be accurately calculated, would be a better paired attribute with travel distance to deliver both cost and other efficiency proxy factors. If the Committee does not want to combine travel and proximity attributes, AOPO would suggest a more significant percent of the available points be assigned for travel over proximity. AOPO also recommends the Committee consider how donor factors impact the efficiency calculation. Longer travel times combined with clinically complex donor organs will create different behaviors (turn downs) as compared to longer travel times with less complex donor organs. To that end, we urge the Committee to consider future incorporation of an attribute related to ex vivo devices that are rapidly improving the ability to utilize previously non transplantable lungs and are changing the ability for lungs to travel long distances. The overall 10% weighting for efficiency is a reasonable starting point, although AOPO suggests that the Committee ensure that this weighting does not contribute to geographic disparities in candidate access to lung transplant that the system is working to eliminate. We also want to ensure that the weighting is significant enough to support the efficient management of the system and avoid wastage which could result if organs are crossing other organs in the air without delivering meaningful clinically different outcomes for lung candidates as measured at the system level. o Multi-Organ: Does the proposal need to be adjusted to allow OPOs more discretion to offer from the heart list before offering the heart to candidates in need on the lung list who have a composite allocation score of at least 28? AOPO supports language that provides OPOs more discretion in allocation in general, and in particular, in the early implementation of continuous distribution. Providing OPOs discretion to allocate from the heart list before allocating from the lung list for patients with composite allocation scores of 28 will allow OPOs to address circumstances unique to donor situations that may arise. While the committee has done an admirable job of attempting to factor in all variables that might impact the relative priorities of the two lists, logistical challenges or unique circumstances will arise in which OPO discretion will be essential to maximize the benefit of donated organs. For example, OPOs may be faced with a deadline for recovery while simultaneously facing clinical circumstances requiring significant lung “recruitment” in donor management. In such a circumstance, because the heart team usually requires time to mobilize a team to perform the heart recovery, delaying heart placement while attempting to improve lung function could result in the heart not being utilized.

American Society of Transplantation | 09/29/2021

The American Society of Transplantation is supportive of this proposal and appreciate the thoughtful effort that went into its development. We urge the OPTN to continue to seek better ways to measure cost when referencing proximity. We believe that as currently proposed, cost and proximity vs distance are both essentially looking at distance. The weighting of these elements is virtually the same using current measurements for cost unless long distances are involved. We offer the following feedback for consideration: ? 1.??Equal balance of waiting list survival weight and post-transplant outcomes:? The options compared appear to be 2:1 and 1:1 weighting with reference to waiting list survival and post-transplant outcomes.? Were other weightings explored?? ? Page 13 states that the post-transplant outcomes measure included outcomes predicted out to 5 years, rather than one year.? However, the example provided (figure 8, page 17, shows modeling based on?2-year?post-transplant survival. Figure 8 does show that the 1:1 weighting?results?in the best overall composite (1-year waiting list survival and 2-year post-transplant) outcome.? This is based on the combined weighting of 40, 45, and 50% of the total CAS. Modeling for higher combined weighting is not shown and thus, it is hard to know why the 50% combined weighting was selected?particularly as the composite outcome at this weighting does not appear to have reached a peak/inflection point.?? ? • Based on the modeling provided it does appear that 1:1 weighting of waiting list survival and post-transplant outcomes is preferable to a 2:1.? • It is unclear how 2 versus?5-year?post-transplant survival impacts the model as only 2-year post-transplant survival is shown? • Combined weighting of pre- and post- transplant is shown to a maximum of 50% of the total CAS.? The impact of higher combined weighting should be explored/shown?? • Methods for determining and reporting all variables used to compute LAS should be rigidly standardized.? Currently there is potential for variability in reporting resting oxygen use and?6-minute?walk distances.? This is further confounded for centers at altitudes significantly above sea level.? ? 2. Pediatric waitlist survival score? There are fewer pediatric patients that receive lung transplants compared to other organs, and we are happy that the pediatric patients are being given priority in allocation schemes. However, the proposal as written reverses recent changes to the lung allocation policy that prioritize pediatric donors going to pediatric candidates under the age of 12 (in addition to the challenges related to incorporation of a subset of the candidate population for which modeling doesn’t exist for a score component, this issue also exposes the fact that this proposal eliminates the aspects of current policy where subsets of donors are prioritized differently). Specifically, page 20 suggests that candidates

ASHI | 09/28/2021

The American Society for Histocompatibility (ASHI) and its National Clinical Affairs Committee (NCAC) appreciate the opportunity to comment on the proposal of establishing the framework of continuous distribution for lung allocation and the use of composite allocation scores in lieu of the current classification system which rely on hard boundaries defined heavily by donor characteristics such as donor age, blood type and distance of donor hospital from candidates’ transplant center. ASHI is in favor of this proposal and welcomes the inclusion of candidates’ specific biological disadvantages with regards to histocompatibility (i.e. CPRA and blood type) as attributes for formulating the individual composite allocation scores to improve transplant access for the highly sensitized, difficult-to-match patient population.

Stuart Sweet | 09/28/2021

I think that this is a step in the right direction for the transplant community as a whole. However, during the process of development two aspects of current policy (stratifications based on donor factors and scores based on modeling that don't apply to all candidates) were not fully addressed, leading to potential concerns for pediatric lung transplant candidates. First, with regard to stratification based on donor factors, most of the current allocation policies have separate stratifications based on donor age (pediatric vs. adult). Some also have separate stratifications based on donor quality such as DCD status or KDPA. Not stratifying based on donor age eliminates one of the long standing components present in the current LAS intended to ensure that pediatric patients have adequate access to donor lungs. For the most part, similar priority is provided by the patient access factor. But one aspect that isn’t fully addressed in the proposal is the fact that adolescents will go from receiving 73% of their organs from adolescent recipients to receiving more than 80% from adult donors. Because the post-transplant survival model includes donor age as a factor, this is felt to contribute to the predicted increase in adolescent 2 year post-transplant mortality in the TSAM report. The proposal suggests that this will be mitigated by donor selection practices (the proposal is silent on whether effectively having fewer viable donors in the pool of offers predicted to go to children will affect pediatric waiting list mortality) and that the Committee plans to monitor this closely. I have concerns about this because the small numbers of pediatric lung transplant recipients will make seeing a statistically significant difference in outcomes difficult. Moreover, in the long run the OPTN is going to need to address this for other organs, including heart, where there is data to support prioritizing pediatric donors being given to pediatric recipients. So I would prefer to see this addressed more clearly, at a minimum with an analysis and mitigation plan, prior to adoption The second, and related, aspect is that the proposal essentially eliminates current policy that prioritizes offering pediatric lung donors to candidates in the 0-11 age group first within 1500 miles of the donor hospital. Because children under 12 are not assigned an LAS score, the medical urgency scores for candidates aged 0-11 were constructed using population data. Therefore priority 1 candidates < 12 years of age will get only of 20.54 of 50 potential points for medical urgency and post-transplant outcomes combined (priority 2 candidates receive 19.07 points). Although this was discussed many times during the course of proposal development, I don’t think I’ve seen modeling that reassures us that this proposal won’t consistently put age 0-11 candidates behind adolescents as seems likely to occur. If that hasn’t been done, I would encourage seeing that information before making a final decision. And, as above, if the proposal goes forward as written, I would prefer to see an analysis and mitigation plan prior to adoption. I would encourage the committee to address these concerns prior to approval/implementation.

Region 10 | 09/28/2021

Region 10 sentiment: 2 Strongly Support; 9 Support; 7 Neutral/Abstain; 1 Oppose; 0 Strongly Oppose Comments: The members of region 10 are supportive of the proposal. There was a concern raised about race and the use of 5 year post transplant survival as one of the attributes. Black recipients historically have had worse three and five year outcomes, which will result in fewer points being awarded to Black candidates. The committee should find a way to mitigate that disparity in the proposed allocation system. It was also noted that the proposed weight given to prior living donors is not enough. In order to achieve the necessary priority, prior living donor points may need to be outside of the Composite Allocation Score. In terms of multi-organ allocation, the committee needs to recognize how complicated Lung/Liver allocation is to the overall allocation process. Even though there may only be one Lung/Liver candidate on the Lung match, many OPOs will hold off on any abdominal allocation until the Lung/Liver candidate has been offered too, which greatly increases the allocation time for a donor thus decreasing efficiency. In regards to efficiency, another member noted that the proposal needs to include monitoring of time to place, added cost, and added case time to allow for outside teams to come in for procurement. Lastly, a member stated that waitlist survival and post-transplant outcomes need to remain at a 2:1 ratio. A 1:1 ratio of these two factors disadvantage programs who choose to transplant older recipients.

United Therapeutics Corporation | 09/28/2021

United Therapeutics Corporation appreciates OPTN’s efforts to expand lung transplant opportunities for patients and approves of the proposal by OPTN titled “Establish Continuous Distribution of Lungs.” In addition to these efforts, we hope OPTN will consider including Scientific Registry of Transplant Recipients (SRTR) data as part of any new data-collection efforts as well as a travel efficiency measure to reduce the logistical challenges associated with air vs ground transport of organs. United Therapeutics Corporation, a publicly traded biopharmaceutical corporation, along with its subsidiaries, Lung Bioengineering Inc. and Lung Biotechnology PBC, the first public benefit corporation subsidiary of a publicly-traded biotech or pharmaceutical company, are dedicated to supporting lung transplant patients through various commercial services and research and development programs, all intended to increase the supply of transplantable organs and improve outcomes for transplant recipients. Of relevance to the current proposal, Lung Bioengineering currently offers centralized ex vivo lung perfusion (“EVLP”) services designed to provide extended preservation and assessment of lungs that may be considered marginal for transplant at our dedicated lung perfusion facilities in Silver Spring, Maryland, and in Jacksonville, Florida. We receive lungs that may be considered marginal for transplant during the initial offering process and perform EVLP on those lungs in a tightly controlled perfusion environment, thus providing transplant clinicians with an extended opportunity to evaluate the lung’s suitability more fully for transplant. As a result, marginal or high-risk donor lungs that would otherwise have been discarded may become available for transplantation. United Therapeutics supports OPTN’s effort to align lung allocation with community, ethical and regulatory goals, and medical advancements. We agree that the proposed composite allocation score could improve current lung allocation policy by reducing waitlist deaths for lung candidates, decreasing the percentage of organ recoveries that require flying, reducing geographic disparities, and positively affecting candidates across all categories. We share these goals and are committed to utilizing any methods possible to increase the supply of transplantable organs. OPTN's effort to replace the current classification-based allocation with a composite allocation score is a more equitable national transplantation process for patients. This should be an effective model, desi! ned to get patients through the system faster and reduce waitlist mortality for the hardest-to­ match patients. Although we support the objectives of this revised allocation model, we think the inclusion of SRTR data as part of any new data collection efforts, would be beneficial to the goals served by the change to allocation practices. Beyond what is recommended in the proposal, OPTN should consider methods to collect more granular data on transplant candidates and transplant recipients. As organs come from deceased donors and go through EVLP (at dedicated EVLP laboratories or at hospitals) it would be helpful to have a separate variable in the SRTR data that indicates if the lung underwent EVLP to evaluate how EVLP is helping the process. Furthermore, United Therapeutics appreciates the Committee's effort to decrease the number of organs transported via airplane. We support the inclusion of travel efficiency as a measure. Assigning points as part of the composition allocation score for travel and proximity could limit the number of organ recoveries that require flying, thus increasing operational efficiencies. This could reduce logistical challenges associated with air vs ground travel. We support any effort to achieve efficient organ placement and avoid disposing of organs that could potentially be transplanted into one of many patients on the organ donation waitlist. United Therapeutics is passionate about increasing the supply of transplantable lungs to address needless patient deaths on the transplant waiting list. We thank you again for the opportunity to provide comments. We look forward to working with the OPTN to help make organ allocation more equitable for patients.

View attachment from United Therapeutics Corporation

Breana Swenson | 09/27/2021

I really think the rules should change. I am further from my transplant hospital and am a hard match. I really want my allocation score to possibly improve with the change.

OPTN Organ Procurement Organizations Committee (OPO) | 09/24/2021

The OPO Committee appreciates the opportunity to provide feedback on the Lung Committee’s Continuous Distribution proposal and provides the following comments: One member shared that multi-organ allocation policy is confusing, with both OPOs and transplant centers struggling to understand the requirements in every situation. Another member remarked that there would likely be pushback from liver programs with not allowing status 1 or high model for end-stage liver disease (MELD) score potential recipients to receive offers ahead of lung-liver candidates. The member continued that this is particularly critical with only lung initially moving to a continuous distribution system, with liver still in geographic circle-based distribution. A member asked about the difference between placement and travel efficiency, and remarked that a combined 10 percent weight didn’t seem sufficient. The member asked what consideration was given to the infrastructure available to facilitate and transport broader sharing, as well as to the impact on getting donors to the operating room, total recovery time, and teams’ ability to travel. The Chair of the Lung Transplantation Committee noted that broader sharing impacted different parts of the country differently across both OPOs and transplant centers, and pointed out that the OPTN does not collect data on travel and logistics. Dividing efficiency into travel efficiency, the number of miles between candidate and donor hospitals, and placement efficiency allows allocation to capture all the ways allocation can be inefficient in order to closely monitor the effects of the change. Another member expressed concern that monitoring transportation following a policy change instead of providing data on potential impacts to efficiency is insufficient. The member remarked that travel and transport systems are already stressed, and that it has become very difficult to get flights to procure livers or even have livers shipped. The member continued, asking why this data isn’t currently being collected. The member commented that it is inadequate to create policy without sufficient data, and that it creates an unfair burden on OPOs and transplant centers when there isn’t transportation available. Another member expressed concern that the current infrastructure may not be able to support further broader sharing.

Region 1 | 09/24/2021

Region 1 sentiment: 3 Strongly Support, 3 Support, 2 Neutral/Abstain, 0 Oppose, 0 Strongly Oppose. Comments: Overall the region supports the proposal. A comment was submitted in support of this proposal, saying it is extraordinary work. One member commented that the MPSC is pulling back from needing longer term outcomes, in regards to using 5 year post transplant outcomes for the composite allocation score. Another attendee asked if the committee had considered giving a specific group or category an “off the charts” number of points, similar to the points given to 100% sensitized kidney patients.

OPTN Pediatric Transplantation Committee | 09/24/2021

The Pediatric Committee thanks the OPTN Lung Transplantation Committee for the opportunity to review their public comment proposal. The Committee provides the following feedback: The Committee appreciates that the proposed weighting of factors in the Composite Allocation Score aligned closely with the priority weighting of the entire stakeholder community, as assessed in the AHP prioritization exercise. The Committee agreed that this is a great start in the transition to continuous distribution for lungs. One of the concerns the Committee expressed was whether the priority points children may receive for height, pediatric priority, and possible biological disadvantages would negate the fact that the lung allocation score (LAS) doesn’t work well for children under the age of 12. The Committee suggested that, in regards to the LAS score for candidates under 12 years old, the post-transplant outcomes score should be re-evaluated over time since it will be the same score given to all lung candidates under 12 years old.

Region 6 | 09/23/2021

Region 6 sentiment: 1 Strongly Support; 7 Support; 2 Neutral/Abstain; 0 Oppose; 0 Strongly Oppose. Comments: An attendee observed payers look at overall costs based on individual candidates; and this could increase variation across the country; the committee should consider this in their proposal.

Region 8 | 09/22/2021

Region 8 sentiment: 5 strongly support, 12 support, 6 neutral/abstain, 1 oppose, 0 strongly oppose. Comments: Region 8 generally supports this proposal with one opposition. A member commented that he supported that the Lung Committee decided to recognize living donors regardless of what organ the living donor donated. A member suggested to be mindful of the adolescent population because the SRTR report suggests that adolescent organs will be allocated less to the adolescent groups. A member asked for clarification on the multi-organ allocation aspect. The member stated that it appears the OPO can offer the heart or liver with the lung if they have a score of 28 – the member asked if this was regardless of what the heart and liver lists look like.

Transplant Administrators Committee | 09/21/2021

The Transplant Administrators Committee (TAC) appreciates the opportunity to comment on this proposal. TAC supports this proposal and particularly appreciates the detailed explanation of how the composite allocation score was developed. TAC also supports the proposed changes to multi-organ allocation since the broad discretion that organ procurement organizations (OPOs) have in multi-organ allocation today can lead to inconsistency in practice and frustration between transplant centers and OPOs. TAC acknowledges the challenges that OPOs face in managing heart-lung allocation and supports clarification of associated policies. Finally, with regard to the proposed changes to the exceptions process, TAC believes that five days is sufficient time for reviewers to vote on exception requests.

Inova Fairfax Hospital | 09/17/2021

On behalf of the Inova Lung Transplant Program, we fully endorse the proposed change to the lung allocation system. We believe this will result in the more equitable distribution of lungs to those most in need. We are particularly happy that projected 1 year post-transplant survival has been replaced with projected 5 year survival. We agree with all the factors accounted for within the new proposed model and commend the committee for their efforts in putting this together.

Anonymous | 09/15/2021

Region 7 sentiment: 7 strongly support, 9 support, 3 neutral/abstain, 0 oppose, 0 strongly oppose. Comments: One attendee recommended the OPTN consider a higher point allocation for travel efficiency and proximity efficiency because the logistical challenges of moving teams and organs are going to increase and asked if there is a way to estimate how much travel will increase. Another attendee commented that the proposal eliminates ABO identical/compatible prioritization and hard geographic boundaries. The proposal also enhances access for candidates with biological barriers like sensitization and small stature; and rebalances medical urgency and post-transplant survival. This could disproportionately impact small programs and regions with less population density. Other attendees expressed that overall the proposal favors broader geographic sharing, this will increase travel time, which may be easier for large programs with robust recovery teams to manage. This will also make it more difficult for candidates with low medical urgency (i.e. low LAS in current system) to get access to good quality donors, since the current allocation system gives low LAS candidates access to donors before they get offered to sicker patients in the next allocation classification. One attendee commented that combined, these trends may make it harder for smaller, low-risk programs to transplant, which could cause these programs to shut down. This may not be a problem in metropolitan areas with multiple lung programs but may be a program in more rural areas with patients who can't travel out of state for health care. Another attendee noted that while modeling is essential, the OPTN cannot model changes in transplant center donor selection practices. Inevitably, these practices will change as the result of such a dramatic alteration in the allocation system. Therefore, it will be hard to predict the presence and magnitude of unintended consequences of this proposal. An attendee recommended that with the incorporation of CPRA utilization, consider require sharing of donor serum for crossmatch, similar to the process for kidneys, when requested by transplant centers to further support access to transplant. One attendee suggested that the OPTN should consider how to mitigate any resulting inefficiencies and model the impact continuous distribution will have on donation for all organs.

Anonymous | 09/15/2021

A few thoughts: 1) This is a great leap forward for organ allocation and provides a solid framework for the OPTN to use moving forward. 2) I am curious how this would change were the allocation to change depending upon donor factors. For instance, the current lung system is different for pediatric vs adult donors. 3) In thinking of efficiency, could we do more to allocate organs to candidates most likely to accept them? From an OPO perspective, we don't think about cost and distance only. We also think about the number of offers and the time to placement. This is really critical when an organ needs to be reallocated after a late turn down. 4) I am glad to see the new benefit for prior living donors. While rare, this is the right thing to do.

Region 9 | 09/14/2021

Region 9 sentiment:? 1 Strongly Support; 7 Support; 4 Neutral/Abstain; 0 Oppose; 0 Strongly Oppose. Comments:?Region 9 overall supports this proposal. A member stated they believed that patients listed for both heart and lung should receive more priority. The member also noted that pediatric lung transplant is rare and questioned the need for the changes related to pediatric lung transplant.

Region 3 | 09/10/2021

Region 3 sentiment: 2 strongly support, 9 support, 4 neutral/abstain, 0 oppose, 0 strongly oppose. Region 3 supported this proposal. One attendee commented they favor giving prior living donors more weight, although living lung donors are rare. Another attendee supported the proposal but stated the policy will change the profile of the patients being transplanted and will require the SRTR to develop a new risk stratification for the patient population. The attendee added they believe this will unlikely change regional transplant rates because the location of organs is not necessarily an important factor for large volume centers. This attendee also questioned if, relative to exceptions, this is a permanent, "indefinite" exception applicable in all situations, especially when clinical issue may improve in a couple of weeks with medical management.

David Homann | 09/10/2021

I think the proposed allocation system is fair and takes into consideration several factors that are currently overlooked. I also believe the proposed system will reduce the wait time for those critically in need of lungs. I feel blessed to have received my lungs and hope that others in need can be equally blessed.

Region 2 | 09/10/2021

• Region 2 sentiment: 7 Strongly Support, 17 Support, 4 Neutral/Abstain, 0 Oppose, 0 Strongly Oppose • Comments: Members of the region supported the proposal. A few members had comments about post-transplant outcomes at 5 years. Five years could be challenging, but 3 year post transplant outcomes could be more attainable. One member noted that 3 year post transplant outcomes are better understood and modeled by the SRTR and these outcomes are reported publicly. It was also noted that clarification is needed for multi-organ patients and how the proposed model will impact how lungs (vs. the non-lung organs) are prioritized for allocation. Additionally, information on whether ECMO Bridge will be incorporated into waitlist and post-transplant mortality models is needed. Another member disagreed with the LAS deprioritizing of prior living donors. Although rare, such candidates should be given priority similar to pediatric candidates. It was also suggested that there should be a sliding scale for pediatric priority; there is not much difference between an 18 year old and a 20 year old.

Living Donor Committee | 09/09/2021

The OPTN Living Donor Committee thanks the OPTN Lung Transplantation Committee for their efforts in developing this proposal and the opportunity to comment. The Committee applauds the proposal’s inclusion of prior living donor priority as a new attribute of lung allocation and strongly supports providing PLD priority for all living donors. The Living Donor Committee has discussed the prior living donor priority question at length and concurs with the Lung Committee's conclusions that prioritizing prior living donors is both medically and ethically justified. We further concur with the Lung Committee's discussion of and conclusion about "sound medical judgment" in connection with this issue that is so important to living donors, their families, and the transplant system. Living donors make a selfless decision to put their health at risk to improve the life of another human being. Though living donation is relatively safe, there is still intrinsic risk associated with organ donation as outlined in OPTN living donor policy, and a lack of systematic collection of data about long-term outcomes. Additionally, as the practice of living donation grows, the Committee recognizes the potential for still unknown risks to be associated with donation. Living donors contribute to the transplant system by donating to one wait listed patient and in doing so, enable transplantation of another waitlisted patient when a deceased organ next becomes available. The Committee supports the societal value of reciprocity to make a donor whole and sending a message to the public that the system values living donors. Additionally, PLD priority offers support and assurance to the donor and the donor’s families that the system will take care of them should they ever need a transplant. The Committee strongly supports adding PLD Priority to lung allocation and providing the same level of priority to all prior living donors as proposed.

Anonymous | 09/02/2021

I think kids should be given the highest chance of receiving a gift. Then by need and health of recipient . Post is all up to the recipient and how they protect that gift of life

Anonymous | 08/30/2021

I know that the committee has a lot of information and considerations to take in for this policy. What I think is important. 2yr survival—This makes better ethical sense with the ultimate gift of life. Lets do our best to keep our lung transplant patients going a longer period of time. Candidate biology- Lung that fit into one patient may not be suitable to anyone on else on the list. Lets make sure that size is taken into account and PRA HLA avoids. Efficiency- Time flying to donor hospital, time transporting, ischemia time. All matters. Proximity matters.

Anonymous | 08/30/2021

Region 5 sentiment: 8 strongly support, 10 support, 10 neutral/abstain, 0 oppose, 0 strongly oppose. Region 5 supports the proposal to Establish the Continuous Distribution of Lungs. A member questioned why there needs to be a weight given for travel efficiency and proximity – the member believed that weighted just the geographic distance is sufficient. Another member supported the proposal but was surprised to see the one-year wait list factor. The member believes that if a patient can wait one year for the transplant then the patient doesn’t have an urgent need for the transplant. A member suggested that outcome measurement should be expanded to five years post-transplant. A member suggested that medical urgency should be weighted more than just 25 points. A member stated that it’s important to acknowledge and utilize other groups that focus on data and modeling to help make decisions – for example, to look at optimal level of priority to give attributes like cPRA and make sure there aren’t unintended consequences. A member suggested to think about center effect and center specific metrics that may influence allocation policy. A member pointed out that since many transplant centers do not enter unacceptable antigens for lung recipients, the modeling for cPRA may not be accurate. The member suggested using kidney cPRA data to do the modeling. A member suggested to consider higher points for supersensitized (>90% CPRA) candidates – to consider sensitization (at least >90% CPRA) status factored for waitlist mortality and post-tx outcome points. A member stated that they agree that post-transplant outcomes should be a part of the score and that the value for a listed patient should be the center data rather than the average national data. A member supported the proposal but pointed out that post-transplant survival scores, for pediatric candidates, should be re-evaluated over time (potentially every 3-5 years).

Anonymous | 08/27/2021

5 strongly support, 13 support, 2 neutral/abstain, 0 oppose, 0 strongly oppose. Region 4 supported this proposal. One attendee commented OPOs should have discretion when allocating multi-organs as they increase the number of DCD donors and situations with resources and logistic restraints. Having discretion without running into policy constraints is important to maximize the donor gift. Any flexibility for OPOs around a cutoff point is worth some serious consideration. Another attendee stressed the importance of monitoring the system once implemented to make sure the weighting is correct. One attendee commented that proximity efficiency makes sense, but they would be concerned that travel efficiency becomes a slippery slope into cost as a factor for what should remain primarily a clinical decision regarding CAS. Another attendee commented that they particularly like the 1:1 relationship between waitlist death and long-term survival, and use of a longer-term survival component than one year. One attendee commented that they are excited to see this work. They went on to comment that as we seek to maximize lung placement, this appears to improve the opportunity to get to the patient most in need while providing reasonable balance of the logistics, travel, and timing. Finally, an attendee commented that they support the CAS and it is a major advance over LAS. They went on to recommend the committee consider changing "height" to "lung volume."

dawn freiberger | 08/25/2021

Hi, I am mostly in agreement with this proposal. My only concern is the aspect of long term survival benefit as being part of the consideration. It is very difficult to predict long term survival in this population. If a center opts to list a patient, they have likely taken this both short term and long time survival into consideration to the best of their ability. There is so much that goes into a patients outcomes aside from just medical issues such as adherence, social issues, etc. These considerations are not part of the LAS system because they are subjective, and unpredictable as are many of the medial issues. Hopefully the individual transplant programs consider all of these issues along with medical aspects before deciding to move forward with listing a patient. thank you

Andrew Flescher | 08/19/2021

This was a detailed, clear paper and I appreciate the substantial thought which went into it. The committee did not punt, but came down with clear articulation of how attributes should be weighted and why. It caught my attention, as I am sure it did many, that medical urgency now carries the same weight as post transplant outcomes, whereas before it carried double. My concern is that this might (1) exacerbate hardships experienced by already vulnerable populations, e.g., those in the most dire straights medically (which is a population which historically overlaps with disadvantaged or underserved groups) and (2) provide further impetus for practitioners to engage in outcomes-based, or "stats-driven" medicine. A more minor concern is that this move might also induce gaming of the system, despite efforts to be transparent. From double to equal seems to be a big leap. Perhaps, therefore, more justification than currently appears should go into explaining the proposed modification. I am especially interested in the extent to which this move was based on community feedback. Was the move made because of its feedback, or despite it? If the latter, on what other basis?---Andy Flescher, Vice Chair of the Ethics Commitee

Anonymous | 08/13/2021

It appears that this proposal puts pediatrics at the top of the list each and every time. Has there been any national survey or discussion related to pediatric patients being first in every line? I'm not saying I' against it, I'm just asking the question, and to be transparent, feel the question should be asked before such a proposal is passes. Again, list the Continuous Distribution of Kidney & Pancreas, this is extremely complicated to understand because of so many factors. Being able to explain it to patients so they understand is critical. Transparency in organ distribution is iperative.

PADV | 08/10/2021

It would be helpful to see what a test match run would look like under the proposed weighting. With only 10% of points allocated to efficiency, one may estimate that a donor match run from the east coast could be populated now by a larger number of centers from across the entire US ( vs the number within the 500nm radius from the donor hospital currently). This alone will cause inefficiencies in the organ offer process particularly if transplant centers do not utilize current screening criteria effectively. The list may be saturated with patients for whom the tx center is truly not interested in donors from a far distance and may have other medical comorbitites that are incompatible with their recipient. Screening filters for thoracic organs are currently inadequate and may not offer a transplant center the granular information to effectively screen donors. Traditionally these center and patient screening tools are set to the widest parameters. Better screening tools and rules requiring their utilization need to be developed to advance this policy goal. Simply thinking that centers will adapt and utilize these tools voluntarily is inconsistent with historical practice and needs to be addressed. Also under this weighting consideration outlined in the policy high soring candidates will be entertaining multiple organ offers now simultaneously. This is good for an individual candidate but needs to be weighed against the potential detriment of the overall system. We have experienced with other broader organ sharing, frequent late organ declines by transplant centers and frequent reallocation of organs. The case time for organ donation has doubled since 2008 from a median of 24hrs to currently lasting 48hours. Allocation policy that makes the matching of donors and recipients more complicated by adding more centers into the mix needs to be balanced with providing the OPOs the rules and the tools to make the process more efficient. Policies around acceptance of only one organ per candidate and defining the terms of acceptance of an organ need to be addressed prior to the implementation of any new allocation policy. We are fully supportive of the continuous distribution model but OPOs desperately need state of the art tools and transplant center accountability in acceptance behavior to make the system more efficient. The process of offering and accepting organs needs desperate overhaul to allow us to be better stewards of these precious gifts. I urge the committee to ensure these rules and tools are in place prior to any policy implementation and not just a future promise.