The New Kidney Allocation The New Kidney Allocation SystemSystem

Gautham Mogilishetty, MDAssociate Professor of Medicine

Division of Nephrology and Transplantation

University of Cincinnati Medical Center

Disclosures

I have no disclosures relevant to this presentation

PerspectivePerspective (as of 8/28/15; Source: UNOS.org)

• There are currently 133,721 people waiting for lifesaving organ transplants in the U.S.Of these, 108,915 await kidney transplants.

• In 2014, 17,109 kidney transplants took place in the U.S. Of these,

11,570 came from deceased donors and

5539 came from living donors.

PerspectivePerspective (as of 8/28/15; Source: UNOS.org)

– On average: • Nearly 3150 new patients were added to the

kidney waiting list each month in 2014.• Every 15 minutes someone is added to the

kidney transplant list • 14 people die each day while waiting for a life-

saving kidney transplant

– In 2012, 5,209 patients died while waiting for a kidney transplant.

The Gap Continues to WidenThe Gap Continues to Widen(All organs = 122,352; Kidney = 101,055; Liver = 15,159; Pancreas = 1,050)

Kidney

Source: http://optn.transplant.hrsa.gov/media/1049/organshortage.png

All organs = 122,352; Kidney = 101,055; Liver = 15,159

2012 Annual Report

US is divided into 11 geographic US is divided into 11 geographic regions OPTN/UNOSregions OPTN/UNOS

PREVIOUS NATIONAL DECEASED-PREVIOUS NATIONAL DECEASED-DONOR KIDNEY ALLOCATION POLICY DONOR KIDNEY ALLOCATION POLICY • Kidney by age- SCD, ECD and DCD• Deceased-donor kidneys are allocated by

blood group • Geographic sequence of kidney allocation-

kidneys are allocated locally first, then regionally, and then nationally.

• Mandatory sharing of zero-antigen-mismatched kidneys

• Kidney payback

Previous Points SystemPrevious Points System• Waiting time-begins when an active candidate listed- 1

point for every year.• Sensitized candidates-CPRA of 80% or greater assigned 4

points • Quality of Antigen Mismatch-DR locus 2 points if there are no DR mismatches 1 point if there is 1 DR mismatch

• Pediatric Kidney Transplant Candidates-4• Prior Living Organ Donor- 4• Medical Urgency – no points

WHY DO WE NEED A NEW WHY DO WE NEED A NEW SYSTEM?SYSTEM?( Went into effect 12-2014)( Went into effect 12-2014)

Higher than necessary discard ratesImproved graft survival rates with unrealized graft years as well as unnecessarily high re-transplant ratesVariability in access to transplants for candidates with certain blood types, sensitization levels, and geographic locations

Kidney Allocation Score (KAS)Kidney Allocation Score (KAS)• Three concepts to determine a candidate Kidney Allocation Score (KAS):

• 1. Dialysis Time (DT): Time spent on dialysis allows candidates to gain priority over the period they receive this treatment, adding the essential element of justice into the allocation system.

2. Life Years from Transplant (LYFT): Determines the estimated survival that a recipient of a specific donor kidney may expect to receive versus remaining on dialysis. LYFT is primarily a measure of utility.

3. Donor Profile Index (DPI): Provides a continuous measure of organ quality based on clinical information, providing a better metric for deciding which organs are appropriate for which candidates.

• LYFT, DPI, and DT are incorporated so that kidneys are matched to candidates based on the expected survival of both the kidney and the recipient.

Preview of Expected Preview of Expected Outcome form the new KASOutcome form the new KAS

New system forecasted to result in:Approximately 8,000 additional life years gained annuallyImproved access for moderately and very highly sensitized candidatesImproved access for ethnic minority candidatesComparable levels of kidney transplants at regional/national levels

Major Allocation ComponentsMajor Allocation Components

• Replaces SCD/ECD with KDPI• Add longevity matching• Increased priority for sensitized candidates/cPRA sliding

scale• Include pre-registration dialysis time

• Incorporated A2/ A2B to B

• Base pediatric priority on KDPI• Remove payback system• Remove variances

SCD and ECD ?

Revised Kidney Classifications:Revised Kidney Classifications:

•Previously, kidneys were classified as coming from either

- Standard Criteria Donor (SCD)

- Expanded criteria donor (ECD)

- Donation after Cardiac Death (DCD) •New System now uses:

- Standard Criteria Donor (SCD)

- Donation after Cardiac Death (DCD)

- Public Health Service High Risk (PHS)

OVERVIEW OF POLICY

Inclusion of Estimated Post Transplant Inclusion of Estimated Post Transplant Survival (EPTS) and Longevity MatchingSurvival (EPTS) and Longevity Matching

• Previous system did not include measure of potential longevity with transplant

• Considering longevity for some candidates could reduce the need for repeat transplants

• Four medical factors used to calculate EPTS score– Age– History of diabetes– Length of time on dialysis– History of prior transplant

OPTN/SRTR• SRTR established the score by analyzing the relationship

between characteristics of deceased donor kidney recipients and their survival times after transplant

• A candidate's EPTS score can range from 0% to 100%• The EPTS score is not used in allocation of kidneys from

donors with KDPI scores greater than 20%• The candidates with EPTS scores of 20% or less will

receive offers for kidneys from donors with KDPI scores of 20% or less before other candidates at the local, regional, and national levels of distribution

EPTS Calculator

How does it impact? How does it impact? • Candidates with lower EPTS scores tend to

be younger

• Diabetics tend to have higher EPTS scores

• Prior solid organ transplant

• Those having spent many years on dialysis

EPTS in tandem with KDPI

Early Returns – New KAS

Source: UNOS.org

Improved longevity matching in the new KAS

Longevity MatchingLongevity Matching

• Longevity matching will affect different regions and DSAs differently because of the effects of multi-organ transplants

• DSAs with active multi-organ transplant programs or large pediatric programs will absorb more of the KDPI < 20 donor kidneys

• Despite this, there appears to be an effect already (may be as much due to dialysis waiting time bolus effect)

Regional Sharing for KDPI>85%Regional Sharing for KDPI>85%• First level of allocation for KDPI>85% is

Local+Region• Determine which candidates may benefit from a

shipped KDPI>85% organ • Update acceptance criteria for imports• Get the kidney to a willing recipient with less cold

time – increase utilization of marginal kidneys

1.6%7.2%

12.5%17.8%

24.5%29.5%

36.3%

46.1%

55.0%

69.9%

91.5% 90.0% 89.0% 87.9% 86.6% 85.2% 83.7% 81.9%78.9%

76.3%71.9%

0%

10%

20%

30%

40%

50%

60%

70%

80%

90%

100%

Kidney Donor Profile Index (KDPI)

Discard rate

Graft Survival & Discard Rates by KDPI – Broader Sharing for High KDPI Kidneys

Gradual decline in graft survival, yet steep increases in kidney discard rates.

2-year graft survival

Source: Darren Stewart, UNOS Research

Waiting TimeWaiting Time

• The new KAS is still a primarily waiting time driven system

• Aside from “fairness”, a waiting time driven system was thought to increase predictability for candidates and allow transplant centers to better manage waitlist management and patient flow

Revised Waiting Time Revised Waiting Time CalculationCalculation

Previous policy begins waiting time points for adults at or after registration with:

o GFR<20ml/mino On Dialysis

Current policy awards waiting time points for dialysis time prior to registration:

o Applies to both pediatric and adult candidateso Better recognizes time spent with ESRD as the basis for priority

Policy for assigning waiting time points based on GFR remains the same:

o Waiting time points begin on date at or after registraion with GFR <20ml/min

Early Returns – New KAS

Source: UNOS.org

Early “bolus” effects of the new KAS – Dialysis Waiting Time Effect?

Early Returns – New KAS

Source: UNOS.org

Younger patients more likely to accumulate more dialysis time?

Changes to Immune Changes to Immune Sensitivity MatchingSensitivity Matching

• Sensitized candidates wait substantially longer due to biological challenges

• Some candidates are so sensitized, they require access to a larger pool of kidneys to find a match

• Current system will give national priority to individuals with cPRA 99-100%

Previous

Early Returns – New KAS

Source: UNOS.org

Early “bolus” effect of the new KAS

Modifications to Blood Type Modifications to Blood Type Subgroup MatchingSubgroup Matching

• Candidates with blood type B face biological challenges to matching

• Many blood type B candidates are ethnic minorities

• Current system will allow access for blood type B candidates to additional kidneys from donor with specific subtypes of blood type A

Unmodified Classification: Prior Living Unmodified Classification: Prior Living Organ DonorOrgan Donor

•Prior living organ donors receive the same level of priority as current policy

•Living organ donors get additional priority and 4 points with EVERY EVERY new registration

Modified Classification: Modified Classification: PediatricPediatric

• Prior policy prioritizes donors younger than 35 to candidates listed prior to 18th birthday

• Current policy will provide comparable level of access while streamlining allocation system

• Current policy will

– Prioritize donors with KDPI scores <35%

– Eliminate pediatric categories for non 1-ABDR KDPI >85%

• New KAS will challenge transplant centers to evolve their waitlist management strategies

• Predictability for candidates and transplant centers was an important consideration in the new KAS and was considered and balanced with multiple other objectives of the system

• The changes in candidate age, comorbidities and other medical factors present as much of a challenge to waitlist management, and the cost and burden on transplant centers needs to be considered in global decisions about staffing and reimbursement

SummarySummary