Kidney Paired Donation Michael A. Rees, M.D., Ph.D.

Ohio Solid Organ Transplantation Consortium OSOTC - Audrey B. Bohnengel, Ph.D. Children’s Hospital Cincinnati - Maria H. Alonso, M.D. Cleveland Clinic - David Goldfarb, M.D. Ohio State University - Mitchell L. Henry, M.D. Miami Valley Hospital - Scott Johnson, M.D. University Hospital Cleveland - Mark Aeder, M.D. University of Cincinnati - E. Steve Woodle, M.D. Akron City Hospital (Summa) - Tanmay Lal, M.D. Anchor Enterprises - Alan Rees University of Cincinnati Johnathan Kopke University of Cincinnati - Johnathan Kopke

Other Contributors Harvard - Alvin Roth, Ph.D. Boston College - Tayfun Sönmez, Ph.D. University of Pittsburgh - Utku Ünver, Ph.D. Carnegie Mellon University - Tuomas Sandholm, Ph.D. Carnegie Mellon University – David Abraham, B.S. Johns Hopkins University - Robert Montgomery, M.D, D. Phil. Johns Hopkins University- Dorry Segev, M.D. Johns Hopkins University - Dorry Segev, M.D. Johns Hopkins University - Sommer Gentry, Ph.D. Columbia University - Lloyd Ratner, M.D. Massachusetts General Hospital - Frank Delmonico, M.D. University of North Carolina - Ken Andreoni, M.D.

A Kidney Paired Donation Donor A Donor B Recipient A Recipient B X X

A Paired Kidney Donation

Strategy 100 donor - recipient pairs generates 4,950 potential paired exchanges.

Potential Donations = n(n-1)/2

Number of Pairs Required

Registrations per prior LRDs R = 0.114

Point System 1.Wait time 2.Distance 3.Recipient vs. Donor Age Disparity 4.Donor vs. Donor Age Disparity 5.HLA Match 6.Pediatric Bonus 7.PRA Bonus 8.CMV/EBV Bonus 9.Blood Group A/B Bonus CategoryPoints 3+ 5/ /2 6 2/2 6

Data Entry Screens

Medical Reviewer Screens

All medically feasible matches from 41 pairs

Optimizing matching of 8 pairs

Number of transplants versus quality of the match 4 matches - 50 points3 matches - 60 points

2-way Solution

3-way Solution

4-way Solution

Multiple Approach Solution

Overall Crossmatches to perform

With 3 x-matches positive

All but one 2-way match lost

Results to Date The Alliance for Paired Donation incorporated in August 2006 and began enrolling transplant centers in October Currently over 70 transplant programs in 24 states participate and over 30 more are considering partnering with the APD. Since March 2007, the APD has performed 32 paired donation transplants with 2 more scheduled. In the January match run there were 145 pairs and we have found potential matches for 22 patients involving 12 transplant centers.

Results to Date Registered pairs ABOi = 60%, 40% crossmatch incompatible. Registered candidates: PRA % in 36%, 10-79% in 32 % and <10% in 29% First 32 transplant recipients PRA % in 22%, 50-79% in 19%, 25-49% in 22% and <25% in 38%. Overall, 41% of the transplanted recipients had a PRA > 50%. Registered candidates blood type: O in 53%, A in 25 %, B in 18% and AB in 4%. First 32 transplant recipients blood type: O in 38%, A in 41 %, B in 19% and AB in 3%. Donor blood type was O in 38%, A in 41%, B in 14% and AB in 8% of the first 32 donors.

The Never-Ending Altruistic Donor Michael A. Rees, M.D., Ph.D.

Paired Donation: Incompatible but willing living donors

The square cannot give to the circle

The circle cannot give to the square

Paired Donation: The square gives to the square, the circle to the circle

What if not done simultaneously?

Reneging is possible – with loss of the “bargaining chip” of the incompatible donor’s kidney

Common Situation: Not Reciprocal incompatibility

Altruistic Donor Chain

What if not done simultaneously?

Reneging is possible – but the “bargaining chip” of the incompatible donor’s kidney is not lost. Therefore simultaneous procedures are NOT required.

Simultaneous Altruistic Donor Chain Deceased Donor Waiting List

Never-ending Altruistic Donor Start a new Altruistic Chain

Never-ending Altruistic Donor continues

Never-ending Altruistic Donor

The First Never-Ending Altruistic Donor Chain

Optimizing NEAD chain matching Each circle represents an incompatible donor/recipient pair

Who can donor 1 give to?

Who can donor 1 give to?

Who can donor 1 give to?

Who can donor 1 give to?

Who can donor 1 give to? st

Who can donor 1 give to? st 2 nd

Who can donor 1 give to? st 2 nd 3 rd

Who can donor 1 give to? st 2 nd 3 rd 4 th

Only pair 4 can give back

Can we do better? st 2 nd 3 rd 4 th

All possible matches for pair

All possible matches for pair

All possible matches for pair

All possible matches for pair

All possible matches for pair st

All possible matches for pair st 2 nd

All possible matches for pair st 2 nd 3 rd

All possible matches for pair st 2 nd 3 rd 4 th

The 4 th best choice for both th

Optimizing NEAD chain matching Each circle represents an incompatible donor/recipient pair

Imagine that an altruistic donor gives to pair one AD

Pair one’s donor converted to an “altruistic donor” AD

Pair one has four possible choices st 2 nd 3 rd 4 th AD

Pair one’s converted “altruistic donor” can now give to pair st AD

Pair twelve’s donor converted to an “altruistic donor” st AD

Pair twelve’s donor gives to the best possible match st AD 1 st

Pair eight’s donor converted to an “altruistic donor” st AD 1 st AD

NEAD chain matching improves both quantity AND quality of matches st AD 1 st AD 1 st

Our Second NEAD chain

3 states, 3 time zones, 3 transplants