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Update on Continuous Distribution of Kidneys and Pancreata

eye iconAt a glance


In December 2018, the OPTN Board of Directors approved the continuous distribution framework for allocation of all organs. Continuous distribution will rank waiting list candidates based on points related to various factors, such as medical urgency, post-transplant survival, candidate biology, patient access, and placement efficiency. Continuous distribution will remove the hard boundaries built into the current framework to increase equity for patients and transparency in the system.

This concept paper provides an overview of the project’s development process and progress, and offers next steps for continuous distribution of kidneys and pancreata. The paper also requests community feedback that will assist the Kidney and Pancreas Committees’ work.

Supporting media


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Progress so far

  • From September 2020 – January 2021, the Kidney-Pancreas Continuous Distribution Workgroup worked to identify goals and key attributes related to kidney and pancreas transplantation.

Proposed concept

  • Continuous distribution will replace the current classification-based allocation system with a points-based allocation system. A points-based framework assigns a composite allocation score to each candidate.
  • A candidate’s composite allocation score will determine the order that organs are offered to candidates. 
  • A candidate’s composite allocation score will consider a combination of donor and candidate characteristics including candidate medical urgency, post-transplant survival, candidate biology, patient access, and placement efficiency.

Anticipated impact

  • What it's expected to do
    • Provide a more equitable approach to matching candidates and donors.
    • Remove hard boundaries that prevent candidates from being prioritized higher on the match run
    • Establish a system that is flexible enough to work for each organ type
  • What it won't do
    • This paper is not a proposed policy change, but will help the Kidney and Pancreas Committees develop a future policy proposal.


  • Proposed attributes for the composite allocation score
  • Additional attributes that should be included
  • Weight of attributes in final composite allocation score
  • Best ways to convert current system into points-based framework

Terms to know

  • Attribute: Attributes are criteria we use to classify then sort and prioritize candidates. For example, in kidney allocation, criteria include medical urgency, blood type compatibility, HLA matching, and others.
  • Composite Allocation Score: A composite allocation score combines points from multiple attributes together. This concept paper proposes the use of composite allocation scores in a points-based framework.
  • Rating Scale: A rating scale describes how much preference is given to candidates within each attribute.
  • Weights: Weights reflect the relative importance or priority of each attribute toward our overall goal of organ allocation. Combined with the ratings scale and each candidate’s information, this results in an overall composite score for prioritizing candidates.

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eye iconComments

OPTN Histocompatibility Committee | 10/01/2021

The OPTN Histocompatibility Committee appreciated the opportunity to review this proposal, and is supportive of the efforts of the OPTN Kidney and Pancreas Committees.

Transplant Families | 09/30/2021

Transplant Families appreciates the opportunity to offer the recipient parents and their family's perspective. We would like to echo much of what the Pediatric Committee and Sharon Bartosh stated above. We believe that in order to not disadvantage children KDPI must be revisited. We are also curious if the new system will address teens who are listed as a pediatric priority and what happens to them if they turn 18 while on the waiting list. This age group already has so much to take over the minute they become adults. We have an opportunity to help them by making sure they keep this priority. Thank you.

Anonymous | 09/30/2021

The Ethics Committee appreciates the work of the Kidney and Pancreas Transplantation Committees in developing this document and for the opportunity to comment on it. A member suggested emphasizing allocation through living donation in the continuous distribution framework to address the organ shortage. A member suggested providing clearer guidance on how the prioritization of multi-organ transplants versus single organ transplants will play out in this allocation framework. A member cautioned that with the change in allocation from regions to nautical miles and now to continuous distribution, it creates potential for the community to lose trust in an ever-changing system. The Ethics Committee is eager to see what the system revision process will look like and suggests an emphasis on patient justice and autonomy. The Committee suggests risk adjusting for disadvantaged groups, specifically those who are geographically far from a transplant center or those groups that do not have insurance. Risk adjustment will also be necessary for transplant centers that are geographically far away from airports with consideration given to how the location will affect its access to donor organs. There was also a suggestion to implement safeguards to prevent kidneys with a high KDPI from being repeatedly offered to the same population. Overall, the Ethics Committee is appreciative of the opportunity to provide feedback and is looking forward to the next phase of this project.

MDPC The Living Legacy Foundation | 09/30/2021

MDPC appreciates the work that the Committee has invested in Continuous Distribution. The increased workload and workflow for OPO’s, Transplant Centers, and HLA labs to evaluate kidney and pancreas offers has been substantial and is expected to increase more with broader allocation. Broader sharing policies require OPOs to expedite allocation post-recovery, due to the volume of patients on the match run being so large; allocating per the match increases CIT while decreasing the likelihood of placement with each decline. Variability in criteria for biopsy and pulsatile perfusion has led to challenges in acceptance and re-allocation of kidneys. Universal systems for virtual crossmatch and consistent practice among OPO’s for blood crossmatch are important considerations in efficient allocation systems. MDPC supports innovation in predictive analytics to match organs available with transplant programs who have a high likelihood of accepting an organ based on past acceptance practices. Prioritizing patients according to ETPS favors patients who are expected to have better outcomes provides stewardship of the gift of donation from the donor family. MDPC favors the utilization of organs from donors that would have higher risk for long term graft/patient survival with recipients that would benefit from transplant versus the risk of not receiving a transplant. Consideration of a points system that includes hard to place kidneys could improve utilization. Due to the smaller number of pancreas transplant programs, the logistics of coordinating pacreata recovery can have an impact on pancreas utilization. Transportation of pancreata in broader sharing has had an impact on CIT and utilization. MDPC would like to see more data on possible allocation changes before the committee agrees to specific weights on each variable, and more data on the impact of multi-organ allocation in Continuous Distribution.

Anonymous | 09/30/2021

Comments: Region 11 supported this proposal. One attendee commented that social determinants of health care have to be incorporated into these policies. Another attendee commented that the committee should reconsider higher KDPI and hard to place kidneys so that they are allocated efficiently. One attendee commented that getting difficult to place kidneys placed might disadvantage rural centers who have transportation issues; committee should take transportation into consideration. Two attendees recommended that the committee revisit the cost of broader sharing when developing policy. One attendee recommended using points to help place those hard-to-place kidneys because we are not maximizing the placement and outcome of those organs and would ask the community for innovative ideas. Finally, one attendee supported continuous distribution.

Anonymous | 09/30/2021

The Ad Hoc Disease Transmission Advisory Committee (DTAC) appreciates the opportunity to provide feedback on this concept paper and overall supports the Kidney and Pancreas Committees efforts to move toward continuous distribution. 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 committee should consider this in developing its continuous distribution policy proposal, and also consider education or guidance on screening of donors to minimize communication issues about test results for areas with differences in endemic testing.

Anonymous | 09/30/2021

The Pediatric Committee thanks the OPTN Kidney and Pancreas Committees for the opportunity to review their Continuous Distribution of Kidneys and Pancreata concept paper. The Committee provides the following feedback: The Committee expressed the importance of engaging the community in a community-wide exercise, like the Lung Committee did, to help prioritize attributes against each other. The Committee expressed concern about the use of kidney donor profile index (KDPI) as a predictor for outcomes in pediatric patients. There’s evidence that KDPI has an age related inflection point among late teenage donors, which means that pediatric candidates aren’t getting access to kidneys from high quality pediatric donors. A member posed the question whether KDPI should be used for pediatric candidates and whether the cut off at 35% should be the same for pediatric recipients. The Committee suggested considering alternatives to KDPI or analyze whether an alternative may be achievable based on existing data. A member noted an equation had been developed for pediatric donor kidneys, which included weight percentiles, height percentiles, and whether the kidneys were being used as en bloc. Data showed that this equation out predicted KDPI in terms of outcomes. The Committee also suggested focusing on en bloc kidneys as an area to improve access for pediatric candidates.

Anonymous | 09/30/2021

The Minority Affairs Committee appreciates the opportunity to provide feedback on Update on Continuous Distribution of Kidneys and Pancreata from the Kidney and Pancreas Transplantation Committees and provides the following comments: A member clarified that the efficient management for organ placement refers to operationalizing kidney offers from an allocation standpoint and that this aims to decrease cold ischemic time. A member suggested that longevity matching should play a larger role in the continuous distribution model. A member asked the sponsoring committees to consider the geographic difference of Puerto Rico and Hawaii as they develop the model, given that they are non-contiguous areas which may have idiosyncratic geographic and organ allocation considerations. A member requested clarification on how HLA DR matching would be considered in a revised allocation system. Another member confirmed the Living Donor Committees’ involvement with this project and highlighted the importance of prioritization for prior living donors.

Transplant Coordinators Committee | 09/29/2021

The Transplant Coordinators Committee (TCC) appreciates the work of the Kidney and Pancreas Transplantation Committees in developing this document and for the opportunity to comment on it. A member suggested including DR matching within candidate biology. A member cautioned that adding too many sliding scale points could potentially impede equal access and emphasized the necessity to balance equity with quality of life. A member highlighted the importance to ensure that pediatric candidates are not receiving offers for kidneys with a high KDPI. A member expressed concern that placement efficiency points would disadvantage recipients in less populated areas and suggested considering population density in this attribute. A member questioned the role in standardization for placement efficiency across organ systems especially in terms of its impact on multi-organ candidates. A member emphasized the importance of widespread education on this policy change for both transplant staff and patients. A member suggested developing an interactive visual tool where transplant center staff can enter a patient’s various attributes to educate them and do informed consent. Overall, the TCC is supportive of the direction that the Kidney and Pancreas Transplantation Committees are going and is appreciative of the opportunity to provide the transplant coordinator perspective.

American Society of Transplant Surgeons | 09/29/2021

The American Society of Transplant Surgeons (ASTS) strongly supports efforts to move to a continuous allocation system with the goal to increase distribution of organs while providing system transparency. However, we oppose this proposal with the concern that it is too broad and too vague to provide specific feedback. It is unclear to us how this enormously complex, even arcane, re-engineering of the entire allocation system would advance the key strategic goal of increasing the number of transplants performed. It is unclear how this project would increase the efficiency of the transplant system, improve access for candidates, improve post-transplant outcomes, or increase organ utilization. The policy’s concept proposes to use variables to construct and weight allocation that is believed to improve equity for specific populations but would also seem to be synonymous with decreasing access for other populations. This and the likelihood of other adverse unintended consequences seems extremely high. Until the OPTN provides a more cogent explanation of the reasons the community should embark on this journey, we refrain from making any recommendations at this time. We need more information on the goals of this project and a clear explication of how moving to continuous distribution would advance critical strategic goals. We encourage the OPTN to provide a clearer statement of goals, intent, and rationale for this project, as well as tools to help us understand the implications of such a radical shift in the allocation system.

View attachment from American Society of Transplant Surgeons

Association of Organ Procurement Organizations | 09/29/2021

AOPO appreciates the opportunity to comment on the update to the concept document for implementation of continuous distribution for kidney and pancreas allocation. We continue to support this framework as an effective way to incorporate and balance multiple medical and efficiency-based factors in a manner that is patient-focused. Continuous distribution will also provide future flexibility by allowing the OPTN to be responsive in its ability to adjust and change the relative rating of variables over time as organ distribution evolves. AOPO strongly urges the OPTN to consider all relevant factors when developing components of the allocation score for kidney and pancreas allocation. AOPO appreciates the ability to participate in the policy development process and views the ultimate goal of this work as ensuring fair distribution of available organs while maximizing transplantation for the patients most in need. Finally, AOPO would like to stress the importance of the OPTN continuing its work through the identified strategic policy priority to develop and implement policies, process and systemwide tools designed to improve the efficiency of the matching process. This work towards a more efficient system is crucial to support the full value of any allocation framework by facilitating maximum utilization of transplantable organs.

American Society of Transplantation | 09/29/2021

The American Society of Transplantation is generally supportive of this proposal. We recognize that the sponsoring committees have an incredibly complex and arduous task to bring this all together and commend them for their thoughtful and deliberate approach. We offer the following responses to specific questions posed by the sponsoring committees: What other factors should be incorporated into the allocation of kidneys and pancreata within a continuous distribution framework? Do you agree with the Workgroup’s recommended attributes? Are there additional attributes of the current system you would recommend? And what additional attributes would you recommend for consideration as part of a future application? Some other attributes that were discussed and could be considered and given priority points are: patient compliance/adherence, financial factors, multiorgan transplant, and Age > 65 (give preference to elderly who have been disadvantaged previously). Some groups of patients (e.g. patients with diabetes) may be disadvantaged as they may be perceived to have lowest expected survival, and therefore they may be assigned lowest allocation composite score. However, timely kidney transplant may be especially important for these patients as they suffer from high mortality risks on dialysis. The Workgroup asks for community feedback on the shapes of rating scales for each attribute (ex. linear, non-linear, binary, etc.). Additionally, the Workgroup welcomes feedback on how each attribute should be weighted in the composite allocation score. We believe that the simulation models should be developed based on different attributes (with varied scales and weights assigned) to see which models would provide the desired outcomes.?These models should not only predict which groups would benefit but also which groups are predicted to lose. As suggested in the ethics white paper, there needs to be a means?of rapid, iterative lookbacks to see if the agreed-to model is achieving the desired outcomes and pulling the plug on models which aren't measuring up in reality. The examples of unintended consequences include, but are not limited to small centers losing out, increased?cold ischemia time compromising graft outcomes, decreased access for minorities). In addition, the attributes must be rated and weighed in the framework of what we want to achieve- which is to improve patient and graft survival, improve access for minorities, efficiency of system, reduce cost, and utility. In particular we note that measures of compliance or adherence should not be based on socioeconomic status as this could unfairly disadvantage the socially vulnerable. Accordingly, measured values for adherence should be well vetted and validated. Are there other measures of the efficient management of organ placement that should be taken into account in a points-based framework? The new system should not disadvantage patients listed at smaller transplant programs located in the rural/suburban parts of U.S. There is concern that smaller or rural centers could be disadvantaged within?this type of organ allocation system. As such, we request further information on how the sponsoring committees plan to monitor and prevent these potential unintended?consequences for patients listed at smaller, rural?centers. How much importance should be placed on waiting time in the continuous distribution framework? How does the community feel about the idea of waiting time inversion? Waiting time should be important. We are supportive of inverted waiting time which may help to decrease discard rates of high KDPI organs Which kidneys should pediatric patients receive priority points for? Which kidneys should pediatric patients not receive priority points for? And what are some alternatives to KDPI for directing organs to pediatric candidates? Considerations related to pediatrics raise two important issues regarding the current approach to continuous distribution: 1) aspects of the current allocation policies which prioritize subsets of organs (i.e. low KDPI, pediatric, DCD) to specific categories of recipients are not well captured in the proposed approach and 2) situations where a model driving one of the components of the score is not applicable to a subset of candidates (I.e. EPTS for pediatric recipients in this instance) have the potential to disadvantage that subset if not carefully considered. Specifically, this movement to a continuous distribution framework is meant to provide a more equitable approach to matching candidates and donors and to remove hard boundaries that prevent candidates from being prioritized higher on the match run.?We wish to emphasize how important it is to account for children in this system.? We do not have all of the answers but would suggest that children be placed into the model on a continuous distribution based on their age (younger with more priority and the oldest approaching adult priority). Another possibility would be to group children into categories (for example, 1-6 year-olds getting 3 points, 7-12 year-olds getting 2 points, 13-18 year-olds getting 1 point).? The basis for this differential in points would be related to the adverse effects of ESRD on growth and development being more substantial in the younger patients and the life of the patient and the graft.? One major concern is that this proposal does not give much detail as to how children will be allocated kidneys based on KDPI and there are faults with the current system. Currently children are prioritized for kidneys with a KDPI < 35 but this eliminates many kidneys from young donors from being offered to children. The KDPI determination was based on outcomes of adult and pediatric kidney donors transplanted ONLY into adult recipients. There are a lack of data to help determine if younger donors with KDPI > 35 would benefit children the same as an older donor with a KDPI 35 being offered to children. This would allow the transplant hospital to look at the offer from the peds donor and on an individual basis decide if the “match” was reasonable for the child. Any agreed upon CAS needs to be modeled thoroughly to determine pediatric specific outcomes within a new continuous distribution allocation framework prior to implementation. EPTS is currently not applied for pediatric candidates and the PCOP strongly feels that there is a need to either 1) introduce consistency of using EPTS for all recipients, or 2) factor this into the pediatric priority points.? In addition, there is still a concern in the pediatric community about multiorgan transplants taking away good quality kidneys from small recipients. We caution the use of the word “sickest” and stress that the main goal be maximizing the benefit of the donor organs rather than protecting the “sickest” patient. The sickest patients often have the worst outcomes. With the continuously increasing numbers of multiorgan candidates this needs to be addressed. Finally, specific to the phrase: “To be consistent with kidney allocation policy, the Workgroup favors including priority points for prior living donors in pancreas and kidney-pancreas continuous distribution as well.” We believe that exploring expansion even beyond pancreata is valuable here; that consideration should be given to all living donors (regardless of organ donated) having priority for transplantation across all organ types. We see this priority access to pancreas for former living kidney donors as opening the door to this broader consideration. Overall, we believe that prioritizing children bears close observation. We support the need for this to be revisited across other organs, as simply giving children higher priority isn’t always the best use of these organs. Should the initial implementation of kidney continuous distribution mirror current approach to longevity matching, by awarding points to EPTS Top 20 percent candidates for KDPI Top 20 percent kidneys? Or should a more sophisticated approach be considered? We believe that current longevity matching is appropriate We encourage the OPTN Kidney and Pancreas committees to think more broadly about these points in collaboration with the Ethics Committee and other organ specific groups.

ASHI | 09/28/2021

The American Society for Histocompatibility (ASHI) and its National Clinical Affairs Committee (NCAC) appreciate the opportunity to comment on the ongoing efforts in the development of a continuous distribution framework for kidney and pancreas allocation, and the proposed use of the composite allocation score system in lieu of the current classification system with hard boundaries. ASHI is supportive of the initiative and welcomes the inclusion of donor-recipient HLA matching and candidates’ specific biological disadvantages with regards to histocompatibility (e.g. sensitization status, CPRA and blood type, etc.) as attributes for formulating the individual composite allocation scores to improve transplant access, safety and outcomes especially for the highly sensitized, difficult-to-match patient population.

Region 10 | 09/28/2021

Comments: The region had several suggestions for the committees to consider as they move forward toward Continuous Distribution. Several members highlighted the need for more data around possible allocation changes before the committees can settle on specific weights for each identified variable. The region’s biggest concern centered on how multi-organ allocation will factor into Continuous Distribution. One member stated that from the pediatric perspective, multi-organ transplants somewhat neutralize the pediatric priority, which they suspect was an unintended consequence. In the current system, pediatric candidates often miss out on kidneys that are used in multi-organ transplants. As the two committees move forward with Continuous Distribution they should collaborate with the Pediatric Transplantation Committee. Another member noted, the current allocation prioritizes kidney/pancreas ahead of all kidneys. This is important because the mortality on the wait list for kidney/pancreas is quite high and, if not allocated with a kidney, may lead to increased discard of usable pancreas allografts. The member supports kidney/pancreas candidates retaining higher priority over the kidney alone candidates in the new proposed Continuous Distribution allocation proposal. Lastly, another member raised the concern of the limited data that is available after the removal of DSA and Region from kidney and pancreas allocation earlier this year. When the committees look to submit their modeling requests they should include data from the past several years to account for such factors as post-transplant survival and longevity matching.

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

The OPO Committee appreciates the opportunity to provide feedback on the Kidney and Pancreas Transplantation Committee’s concept paper on Continuous Distribution of Kidneys and Pancreata and provides the following comments: One member recommended utilizing longer term outcomes than one-year post-transplant survival, particularly in terms of optimizing allocation for kidney and pancreas recipients. A member remarked that there should be a way to factor in hard to place kidneys, such as a prioritization that takes into consideration the centers accepting and transplanting these organs so that utilization can be improved would be impactful. The member added this is not only helpful to recipients, but to donor families as well, particularly for very young pediatric donors. One member shared that the recently implemented circles-based kidney allocation system has exponentially increased transactions with transplant centers and significantly stressed transportation systems. Transplant centers are increasingly using third party services to receive organ offers, leading to increased inefficiency. The member continued, noting that under broader sharing, there have been upwards of 6000 candidates in the 250 nautical mile (NM) circle on the match run. It is almost impossible to get through that many candidates in an equitable manner efficiently. The member concluded that OPOs need support from transplant centers to more efficiently allocate kidneys, and that DonorNet is inefficient. A member shared that their center has seen significantly reduced kidney offers since implementation of the circles-based distribution, and recommended adding some kind of recognition for veterans as an attribute. The member also noted that their military education is not appropriately considered in the demographic data collection for waitlist, and suggested including demographic questions for military service. The member explained that there should be some kind recognition for veterans with exposure to agent orange and other warfare chemicals, so there is some recognition of why these patients need transplant. One member commented that the hard boundaries aren’t serving patient populations well, particularly the use of nautical miles and the 250NM then national placement boundary. The member continued that education would be critical for patients, and added that there are barriers to broader sharing in differences in practices between transplant centers and inefficient courier systems. The member provided cross-matching as one such example of differing transplant center practices creating inefficiencies. Some centers will do retroactive and virtual cross matching, while others ask for blood samples. As an OPO, only so many donor blood samples can be taken and shared. The member remarked that these kinds of practices should be considered when potential recipients are from so many different transplant centers. Another member agreed that the blood sample issue is an obstacle to efficiency, particularly with unpredictable couriers. The new policy could build something in that would set a limit on the number of blood samples OPOs would be required to send. The member commented that prioritizing virtual crossmatch could be impactful, particularly investing in the knowledge and research required for virtual crossmatching on the transplant program side. A member shared that for efficient management of kidneys, pre-recovery focus in allocation is on equity and fairness, and following the match run. Transplant center behavior varies in terms of serious offer evaluation. Post-recovery, however, the member shared that after 5 or 6 transplant centers decline a kidney for all their candidates, the kidney can become difficult to place. The member continued that these allocation policies will increasingly push OPOs to expedite allocation post-recovery, simply because the volume of patients on the match run is too large. Particularly, transplant centers waiting until they’re primary and taking the full hour to evaluate, and then declining, increases the cold ischemia time on marginal kidneys, reducing their chances of placement. Another member commented that the idea of building in a way to prioritize centers that accept marginal kidneys would be very helpful. The Pancreas Committee Chair also noted that most of the continuous distribution discussion has focused on pre-procurement, and that the feedback to acknowledge and discuss post-procurement is very helpful. One member recommended a dynamic match run that adapts and prioritizes as an organ approaches cross clamp time or as cold time increases, so that there is more weight towards efficiency at a critical point to avoid organ discard. The member also noted that pancreas allocation has become more like liver allocation in terms of transportation timeframes, and recommended thinking about proximity points differently with pancreas and kidney-pancreas versus kidney alone. A member shared that circles-based geography presents its own inequities – the Pacific Northwest has a quarter of a circle and a sparse population, while Nashville has a complete circle in the middle of the country. The member continued that their centers have lost a large geographic area in the circles-based distribution, and that geography is not appropriately weighted. The member recommended that geography be considered as an area, rather than a line or a circle. One member recommended that the need for more air transportation, from a systems perspective, needs to be considered in broader allocation of kidney and pancreas in order to avoid increased discards.

Region 1 | 09/24/2021

A member commented that the ability to adjust the attributes in continuous distribution more nimbly is a major benefit of this system. One attendee mentioned a center’s acceptance of hard to place kidneys as something that the committee might consider while developing continuous distribution. A comment was made regarding the committee reviewing the current sliding scale of points for cPRA, especially those in the range of 90-96, to determine if the points reflect the true biological need of the candidate. Another attendee, referencing the age of recipients and the benefit they receive from transplantation, asked if the committee could consider more nuanced ways of weighting age of a recipient than EPTS. Another member stated that this process would benefit greatly from continued engagement with the community through more group discussions with an adequate amount of time allotted. A comment was submitted that the individual would like to see more data to confirm that continuous distribution will produce meaningful results.

American Nephrology Nurses Association (ANNA | 09/23/2021

ANNA supports

View attachment from American Nephrology Nurses Association (ANNA

Region 6 | 09/23/2021

An attendee appreciated the inclusion of pediatric considerations. Another commenter noted the workgroup may identify groups who are waiting for single kidney that need to be prioritized over multi-organ transplants. An attendee recognized the workgroup’s efforts to increase equity and access, but noted the ideas being discussed only seek to increase fairness for patients on transplant lists. The attendee added these concepts won’t help patients in areas where there is poor access to healthcare, and there needs to be advocacy for these populations. An attendee stated the OPTN should implement the recommended changes quickly.

Region 8 | 09/22/2021

Region 8 generally supports the progress of this update with the following feedback for policy development. A member pointed out that it is important to consider how donor biology will play a role moving forward, especially with pediatric candidates and that there needs to be consideration for pediatric prioritization. A member pointed out that this concept caused his institution to revisit concerns raised during the development of the lung continuous distribution. These concerns are: removal of separate allocation policies based on organ classification (here it is based on KDPI, in the lung policy it was adult vs. pediatric organs), and incorporation of a pediatric population that does not currently have survival models into an allocation scheme that includes them. A member stated that his institution supports this proposal overall but stated that there needs to be strong consideration on the ease of implementation for OPOs and transplant centers. This change will have major impacts to on-call requirements for transplant programs. Further, it is essential to consider ease of delivery of organs to the transplant center and potential increases to cost. A member pointed out that on the OPTN website presentation it was stated that "continuous distribution will provide organ offers to the sickest and best able to benefit from the transplant". Then the member asked, that based on the CAS, how is "sickest" defined since many factors are included in the CAS? Further, how will the current EPTS and KDPI systems be integrated into the continuous distribution framework (e.g., longevity matching). And will donors have a CAS also? The member suggested that there needs to be parity between quality of the donor offer and the candidate survival expectation for best use of the donor gift. A member stated that his institution respectfully asks the Committee to consider a factor for "rurality" of transplant programs as it considers kidney and pancreas allocation. The distance from procurement site alone does not consider commercial flight availability for the more rural transplant centers and the impact that may have.

Transplant Administrators Committee | 09/21/2021

The Transplant Administrators Committee (TAC) appreciates the opportunity to comment on this concept paper, and thanks the Kidney and Pancreas Committees for their work. A member said it is hard to comprehend how the composite allocation score will work for kidney since kidney candidates are not necessarily facing the same time constraints as a heart, liver, or lung candidate. TAC supports continued consideration by the Kidney and Pancreas Committees on how dialysis will factor into the composite allocation score, including how time on dialysis impacts individual patients. Additionally, a member suggested that the committees consider the administrative burden of tracking and reporting data related to the medical urgency attribute for kidney.

Anonymous | 09/15/2021

Comments: There was robust discussion during the meeting regarding CAS, KPDI, and SPK candidates. Several attendees voiced support for the CD framework. An attendee asked about the availability of data to assess pre-transplant mortality risk for solitary pancreas transplant candidates. Others expressed concern that there is the lack of literature to be able to establish a defined way to compare waitlist mortality and medical urgency for a solitary pancreas recipient to that of an SPK recipient. One attendee had concern regarding prioritizing the sickest patients as kidney/pancreas patients who are very sick and likely will not be able to undergo surgery and survive. Some attendees expressed the possibility to quantify hypoglycemic unawareness as an aspect of medical urgency for pancreas recipients. An attendee also asked the committee to consider how to mitigate inefficiencies and model the impact of continuous distribution on organ donation and especially cold ischemic time and discards. There was feedback on how this will impact pediatric patients. Specific concerns included how age will be considered, the priority accorded for dialysis time, priority for patients over age 18 who were listed before their 18th birthday, the types of kidneys (by KDPI or otherwise) that would be offered to pediatric patients and their priority for those kidneys, and how multi-organ and pediatric patients will be prioritized. There was also concern that CD should be carefully modeled to assess the impact on pediatric patients prior to implementation. One attendee also commented that protection for pediatric candidates should be underscored.

Region 9 | 09/14/2021

Members had several comments and feedback for the committees. One member commented that the timeline for this project seemed long and suggested doing whatever possible to expedite it. Several members voiced support for the project overall. A member commented that they hoped the cPRA scale will be more gradual and not jump up so severely at 98%. A member noted that determining the extent of non-primary organ offers to improve allocation efficiency and transplant center unnecessary work burden was needed. One member also remarked that there is much more work to be done on this project.

Region 3 | 09/10/2021

Many attendees had feedback for the committee and provided the following comments. KDPI is a poor predictor of organ quality. Will the committees try to come up with a better metric? The committees should ensure pediatric candidates registered before age 18 maintain priority with the transition. Organ offer filters should be equivalent to an organ refusal, and there should be no advantage for programs to use several organ offer filters. They are effectively preset criteria for refusing an organ sight unseen. It is difficult to get centers to accept KPs, particularly when cold time is increased due to transportation limitations. Commercial air is an OPO’s main, and sometime only, option. Issues with timely transportation need to be taken into consideration throughout the country, not just on the East and West coasts.

Region 2 | 09/10/2021

• Comments: Members of the region had a fair amount of feedback for the committees to consider as they progress with their Continuous Distribution work. It was noted that in service of ethics and efficiency, the committees should prioritize appropriate KDPI/EPTS matching in the evolving allocation system over a simple de-prioritization of patients with higher EPTS scores. If an older/higher KDPI donor is offered, perhaps additional consideration should be given to higher EPTS potential recipients on that match run to maximize organ and recipient survival parity, and thus efficient organ usage. If higher EPTS patients are de-prioritized regardless of the nature of the donor organ being offered, it will medically disenfranchise a large number of the patients we serve. It was also noted that the concept paper suggests that the current system would be changed from a timed system to a points system. This is somewhat disingenuous because points are certainly used in the current system. A future proposal could be strengthened if the hard boundaries that are referenced were clearly depicted in a few allocation runs. Members expressed concern about the increased number of organ offers seen with the newly implemented kidney and pancreas allocation policies. Moving forward the committees should consider ways to improve efficiency of organ allocation. One member noted that geography should have more points than proposed for lungs - it should account for at least 25% or more. Utilization, cost, and outcomes should be evaluated frequently and determine if improvements need to be made. In terms of efficiency, a member noted that donor assessment would be more fluid in a Continuous Distribution system. Another member questioned whether it is necessary to provide prior living donor points for pancreas candidates, since that would be a very rare occurrence. It was also noted that pediatric patients have a lot of years ahead of them and offering them points for best matched kidneys would help prolong their allograft lives and prevent sensitization to some extent. Another member noted that it would be more equitable to reconsider the pediatric designation to a youth designation and that for certain very young adults the allocation should gradually move down a scale as they age into more mature adulthood, perhaps with the scale ending at 25 years old. Lastly, patients at rural programs are disadvantaged by distance to a transplant program, but additionally, the program's distance and access to receiving shipped kidneys. Shipping distance may magnify CIT for rural programs due to logistical concerns. For example, rural kidney programs may not have close access to their own OPO where kidneys are pumped or biopsied. Rural centers may also have distant access to large airports that are utilized for shipping kidneys. With the new allocation system, kidneys are delayed by an additional 12 to 18 hours based on lack of flights. The member urges data collection, and eventually, adjustments to allocation variables if necessary, to reflect potential disproportionate effects of longer shipping distance on rural, disadvantaged patients.

Sharon Bartosh | 09/02/2021

Continuous distribution will replace the current classification-based allocation system with a points- based allocation system. A points-based framework assigns a composite allocation score to each candidate and that score will determine the order that organs are offered. The candidate’s CAS will consider a combination of donor and candidate characteristics including medical urgency, post- transplant survival, candidate biology, patient access, and placement efficiency. This movement to a continuous distribution framework is meant to provide a more equitable approach to matching candidates and donors and to remove hard boundaries that prevent candidates from being prioritized higher on the match run. This concept paper outlines proposed attributes for the CAS and asks for feedback from the transplant community regarding additional attributes that should be included, as well as weighting of attributes in final CAS score and best ways to convert the current system into points- based framework. It is unclear from the proposal how children will be handled within this system and whether they too will be allocated organs on the basis of their CAS. If they are also going to be given a CAS, it is my assumption that they will receive the same weighting for things such as blood type, sensitization, proximity and waiting time. The larger question is related to weight of age. Issues and concerns to consider from a pediatric standpoint are; 1. Weighting of age. Questions needing to be answered are; Should children be placed into the model on a continuous distribution of their age (younger with more priority and the oldest approaching adult priority) or should they be grouped into a few categories (for example; 1-6 yr olds getting xxx points, 7-12 yr olds getting xx points, 13-18 yr olds getting x point). The basis for this differential in points would be related to the adverse effects of ESRD on growth and development being more substantial in the younger patients. 2. Another question we as a community should weigh in on is “should children on dialysis get more priority compared to those listed for a pre-emptive transplant?”. Currently there is no distinction but perhaps we should examine this question. I would tend to favor having children on dialysis prioritized over children not yet on dialysis. I am actually not sure how this is handled on the adult side and whether an adult listed pre-emptively is treated the same as someone who is on dialysis with regard to priority. I presume the number of adults listed pre-emptively is relatively low whereas in the peds side it is a much higher proportion. 3. How will the new system deal with the current policy that allows for children listed prior to their 18th birthday but not being transplanted by their 18th birthday to retain their “pediatric priority” until transplanted. I would be in favor of maintaining this priority within the CAS. This issue will come up with all the pediatric organs since this continued pediatric priority after turning 18 crosses all the organs. 4. The proposal does not give much detail as to how children will be allocated kidneys on the basis of KDPI. Currently children are prioritized for kidneys with a KDPI < 35 but this eliminates many kidneys from young donors from being offered to children. the problem with KDPI in general is that the determination of KDPI was used from data sets that looked at outcomes of adult and pediatric kidney donors transplanted only into adult recipients. Pediatric recipients were not included. Soooo, we don’t have data to help determine how these younger donors with KDPI > 35 fare in children and our community’s suspicion is relatively well in most cases. The fix to this issue is a complete redo of the KDPI using all donors into all recipients. Short of a complete redo of KDPI, the pediatric community would advocate for continued priority for children of kidneys with a KDPI < 35 AND a version of age matching with increased weighting going to pediatric donors with KDPI > 35 being offered to children. This would allow the transplant hospital to look at the offer from the peds donor and on an individual basis decide if the “match” was reasonable for the child. 5. Any agreed upon CAS needs to be modeled thoroughly to determine how children will fare within a new continuous distribution allocation framework prior to implementation. 6. Will multiorgan allocation remain a hard boundary for children? The new proposed system does not address (as far as I can tell) the current prioritization of multiorgan candidates above pediatric candidates, sensitized candidates and prior living donor candidates. With the continuously increasing numbers of multiorgan candidates (see table in attachment) and the previously stagnant peds transplant volume (the new allocation system is resulting in more children being transplanted) this, in the opinion of the peds kidney transplant community, continues to be an allocation policy that needs to be addressed.

View attachment from Sharon Bartosh

Anonymous | 08/30/2021

A member commented that in order for continuous distribution to achieve equity the weighting of each variable will be important - an overweighting of longer distance compared to medical urgency will result in points given to more local patients than those most in need, which would be a step backwards. The member cautioned that the OPTN and committees should be extremely careful not to overweigh physical proximity of donor and recipient or to give too high a coefficient for distance in the overall score, especially for organs that can travel. A member expressed mixed feelings about the use of EPTS, since traditionally wait time has been given a very heavy preponderance for kidney allocation. A member suggested that in order to stratify candidates for medical urgency there needs to be a better predictive tool that can help educate members on the criteria and risk factors for death on the waitlist or progression of CAD or vacular disease that may preclude transplant or result in removal from the waitlist. EPTS is probably too blunt an instrument to predict post-transplant outcomes in order to prioritize and order candidates for transplants. But the member pointed out that EPTS may still be useful for donor/recipient matching. Several members support a non-linear distance formula since cold ischemic times do not correlate linearly with distance from organ donor to recipient location. Another member commented that the driving forces is what is best for the patients and pointed out that there is a cost to fairness and equity. A member expressed the need for a uniform system to do a virtual cross-match but that may be a topic for the Histocompatibility Committee. A member asked for more data on how kidney and pancreas donation effects the pediatric population. A member suggested that movement of the donor from their hospital of origin to a donor center can change placement efficiency and should be considered. The member believes that if there is commitment from the OPOs to have timely transport arranged, this could be minimized. Likewise, travel distance for tissues for physical crossmatches may be important. The member believes the continuous distribution scale should reflect components they have already agreed on as a community as being important: waitlist time, priority to high CPRA, proper pairing of low KDPI donors with those who will benefit the most, and distance from donor hospital to recipient center. This could be improved by a more continuous, fluid scale rather than the sharply defined cutoffs that currently exist, but should continue to reflect and prioritize those already debated topics. A member suggests that it will be very important to be consistent across KDPI categories for pediatric access - the lack of any pediatric priority for KDPI>35% prevents appropriate, efficient matching of small donors (pediatric donors) with small recipients (children) - it is not clear how this impacts discard rate but would be extremely helpful to evaluate SRTR data in more detail as part of this process to consider. Also important a member suggests considering that EPTS is not currently applied for pediatric candidates – there is a need to either introduce consistency of using EPTS for all recipients, or factor this into the pediatric priority points. In the lung continuous distribution proposal, the proposal assigns a standard number of "post-transplant survival" priority points to pediatric recipients because they were previously classified by Status and did not have scores calculated. To ensure system adaptability going forward, though, it may be preferable to have a calculate-able score that will apply to children as well instead of assigning a fixed post-transplant score that will not change despite trends in the overall score distribution.

Anonymous | 08/27/2021

Many attendees had feedback for the committee and provided the following comments: The committee needs to be careful about how they prioritize pancreas and kidney/pancreas candidates because very sick pancreas patients often do not benefit from a pancreas transplant. The committee should use different terminology rather than “sickest” for these patients. The plan to prioritize pancreata or combined pancreas/kidney transplant to the "sickest" patients seems counterintuitive in that neither transplant is life saving and it would seem more prudent to give less priority to these patients when they get sick with the exception of patients who are running out of dialysis access. The committee should proceed carefully with prioritization of patients and have a goal of maximizing the benefit of the donor organs. Committee will need to make sure that when prioritizing the “sickest” patients, that these types of patients are very well defined. It would be difficult to adjust kidney allocation for disease severity. Continuous distribution is a worthy goal, but must not be accomplished at the cost of utility and being good stewards of donor gifts. Pediatric priority and the geographic discrepancies in pediatric access to transplant needs to be carefully considered. Patient education will be needed. This is interesting work but we need to make sure it doesn’t get too complicated for patients. Having a complicated allocation system that is hard to understand could disenfranchise certain populations. It’s extremely important for patient education especially as allocation changes to medical factors and not wait time. Kidney allocation goes currently according to ETPS - which favors patients with better survival. Prioritizing sick patients (which might have higher ETPS) could collide with the ETPS based allocation.

Jason Rolls | 08/17/2021

Today's Regional Meeting featured a presentation by the KP Committee which described the evolving development of a widely continuous organ distribution model. Included were elements being considered in the determination of recipient priority for organ allocation in an evolved system. One of the elements mentioned concerned expected recipient post-transplant survival. In service of ethics and efficiency, I would ask the KP Committee to prioritize appropriate KDPI/EPTS matching in the evolving allocation system over a simple de-prioritization of patients with higher EPTS scores. If an older/higher KDPI donor is offered, perhaps additional consideration should be given to higher EPTS potential recipients on that match run to maximize organ and recipient survival parity, and thus efficient organ usage. If higher EPTS patients are de-prioritized regardless of the nature of the donor organ being offered, it will medically disenfranchise a large number of the patients we serve.

Anonymous | 08/13/2021

What is expected to be the overall national outcomes impact with these priorities? How are psychosocial/financial factors accounted for in the prediction models for longer term outcomes? We know those are both key factors in long term graft and patient survival. It also seems that with points for ease of distribution, this proposal advantages the wealthy and punishes the poor because the wealthy can multi-list in several areas to increase their accessibility. Lastly, and perhaps the most important, 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 imperative.