Table 5.

Factors considered in selection of patients for first clinical trials of pig kidney xenotransplantation

Age 55–65 yr. As the anticipated period of pig graft survival remains uncertain, younger patients, who are more likely to survive until a suitable allograft becomes available, should perhaps be excluded from the initial trials.

No significant health problems except ESKD. A patient with a pig xenograft may possibly (1) require more immunosuppressive therapy than one with an allograft, and (2) may need to return to chronic dialysis, which may be associated with a higher morbidity than initially. It is therefore important that the patient should have no other health problems except ESKD. A patient with isolated polycystic kidney disease might be a preferred candidate.

Blood type B or O, as these patients spend longer on the waiting list for a deceased human donor kidney.

No anti-HLA antibodies (to avoid any risk of cross-reactivity of anti-HLA antibodies with swine leukocyte antigens).

Supported by dialysis, but for <12 mo. Initiation of dialysis will confirm to the patient and his/her family that ESKD has advanced sufficiently to warrant kidney transplantation, but the period of dialysis has not been so long to be associated with complications or lead to general debility.

Fulfill all other criteria for allotransplantation, e.g., absence of potentially life-threatening infections or malignant disease.

Vascular access may be problematic, or is likely to become limited.