How close are we to transplanting animal organs into people?Can animal organs save people on the transplant list?
or, simply: Can animal organs save people on the transplant list?or, precisely: How close are we to transplanting animal organs into people?
Gene-edited pig organs have kept people alive for months; the open question is whether they can replace human donors for years, not weeks.Thousands die waiting for organs. Gene-edited pig kidneys and hearts could close the gap — if they last.
Controlled trials, sparse outcomes — EXPAND targets 50 participants, but no cohort-level 24-week survival distribution has yet been posted; 271 days remains the completed record. Next up — EXPAND primary completion target (expected Oct 2028).
Four tests between here and the goal
Each threshold is a falsifiable claim with a named next test. We move the meter only when a result is public.
The record behind the verdict
Major events set large; context events set small but never hidden. Everything below the TODAY rule is a schedule, not a result.
Borrowed Organs, Blind Immunity
Borrowed Organs, Blind Immunity begins with first vascular organ attempts. The result established the next question for the field.
Primate Grafts and Rejection
Primate Grafts and Rejection moved the field from chimp kidneys reach nine months to baby fae survives 21 days. The results narrowed the next question without closing it.
Virus Risk Meets Gene Editing
Virus Risk Meets Gene Editing moved the field from pig retrovirus infects human cells to who sets trial principles. The results narrowed the next question without closing it.
Preclinical Barriers Begin Falling
Preclinical Barriers Begin Falling moved the field from crispr disables 62 perv copies to life-supporting hearts pass six months. The results narrowed the next question without closing it.
Humans Enter Controlled Trials
Humans Enter Controlled Trials moved the field from gene-edited kidney enters human body to expand primary completion target. The results narrowed the next question without closing it.
Events outside the declared eras
Events outside the declared eras begins with lifetime surveillance horizon. The result established the next question for the field.
Why the meters read the way they do
The learning curves and comparisons that justify each threshold's percentage. Every series is measured, with the source event linked in the timeline above.
The survival staircase
The climb to a line
NOTE — This carries forward the candidate node's recommended metric. Values are individual cases, not a survival curve: compassionate-use recipients differed sharply in illness, donor edits and immunosuppression. Stewart's 250-day point is a published minimum while ongoing, not a final outcome. The one-year line is an editorial near-term goal; the candidate node's ten-year mature benchmark is deliberately not plotted because it is aspirational, not a dated forecast. Brain-dead-body experiments are excluded because they cannot establish recipient survival or durable clinical independence from dialysis.
If the remaining tests pass
Downstream capabilities, drawn dashed because they depend on results not yet in.
Where every number comes from
- International Xenotransplantation Association 2025 position paperpmc.ncbi.nlm.nih.gov
- FDA xenotransplantation guidancefda.gov
- ClinicalTrials.gov EXPAND record NCT06878560clinicaltrials.gov
- NYU Langone EXPAND trial launchnyulangone.org
- AP report on the 271-day completed recordapnews.com
- eGenesis EGEN-2784 IND clearance and patient updateegenesisbio.com
- NYU Langone 61-day immune-mapping studynyulangone.org
- University of Maryland lessons from the first pig-heart recipientmedschool.umaryland.edu
- Science paper on multiplex PERV inactivationpubmed.ncbi.nlm.nih.gov
- Historical review of cross-species organ transplantationpmc.ncbi.nlm.nih.gov