Introduction: Transplant recipients are at elevated risk of COVID-19 infections. Pancreas transplant recipients (PTR) are an understudied group. We wanted to determine COVID-19 vaccination, infection, and breakthrough infection rates in PTR.

Materials and Methods: We performed a retrospective review of 176 PTR performed between 1/1/2014-2/1/2022. Summary data are presented as mean+/-standard deviation. Bivariate comparisons to evaluate characteristics associated with outcomes were performed using Fisher's exact test.

Results and Discussion: The mean age at transplant was 45.3+/-9.1 years, and the mean current BMI 27.9+/-5.6. There were 95 (53%) males, 90 (50.3%) were white, 68 (38%) black, 8 (4.5%) Asian, and 10 (5.6%) others. The majority were SPK recipients (140, 78%). During a mean of 1228+/-687 days of follow-up, there were 12 organ failures (8 P, 2 K, 2 SPK). Of patients who developed a COVID infection, only 2 (3%) patients died (with functioning grafts) from COVID infection. Both were fully vaccinated with 2 and 3 doses, respectively. A third patient died from unrelated causes. 138/176 (78%) PTR were fully vaccinated (>=2 doses of mRNA vaccine), 35 patients remain unvaccinated; 3 had only one dose of vaccine. Among the unvaccinated or partially vaccinated group, 13/38 (34%) patients developed COVID-19 infection. In vaccinated patients, 44/138 (32%) patients developed infections, at a mean of 160+/-94 days after the most recent vaccine dose prior to the infection, or 216+/-75 days after being fully vaccinated. Table 1 shows the distribution of infections by number of vaccines. Among post-transplant infections, 11 occurred during the ancestral wave; 7 during the alpha/beta/gamma wave (December 2020-May 2021), 7 during the delta wave (May 2021-December 2021), and 32 occurred during the omicron wave (December 2021-now).
Interestingly, among PTA and SPK recipients, 45 of 150 patients developed post-transplant COVID infection (30%), whereas in the PAK/other group, there were 12 infections in 26 recipients, for a rate of 46% (p=0.06).

Conclusion: In summary, PTR were vaccinated to a similar degree compared to the general population. Infection rates were similar between vaccinated and unvaccinated PTR. To date, COVID-19 infections occurred in about 33% of PTR. PAK and other/multiple re-transplant recipients had a higher rate of infection compared to recipients of a PTA or SPK. Vaccination alone did not prevent death in 2 recipients. Ongoing precautions, including masking, continue to be advisable.