Kidney Week

Abstract: SA-PO998

Effect of Conversion from Tacrolimus to Cyclosporine on BK Viremia among Kidney Transplant Recipients: The TACCsA-SWITCH Study

Session Information

• Transplantation: Clinical - 4
  October 26, 2024 | Location: Exhibit Hall, Convention Center
  Abstract Time: 10:00 AM - 12:00 PM

Category: Transplantation

• 2102 Transplantation: Clinical

Authors

• Ali, Shaikha Rashid, St Joseph's Healthcare Hamilton, Hamilton, Ontario, Canada

Shaikha Rashid Ali, MD, MBBS

• Png, Hon Shen, St Joseph's Healthcare Hamilton, Hamilton, Ontario, Canada

Hon Shen Png, MBChB

• A. AlGhamdi, Abdullah Ashour, St Joseph's Healthcare Hamilton, Hamilton, Ontario, Canada

Abdullah Ashour A. AlGhamdi, MBBS

• Gangji, Azim S., St Joseph's Healthcare Hamilton, Hamilton, Ontario, Canada

Azim S. Gangji, MD

Background

There is no established treatment strategy for BK-polyomavirus (BKPyV) infection among kidney transplant recipients (KTRs) after initial reduction of immunosuppression. In vitro studies suggest an inhibitory role of cyclosporine on replication of BKPyV. We investigated effect of conversion of tacrolimus to cyclosporine (TAC-CsA switch) on BKPyV viral load (VL) among KTRs.

Methods

We conducted a retrospective cohort study with a pre-post study design investigating effect of TAC-CsA switch among KTRs with persistent BKPyV-VL of more than 10,000 IU/ml (equivalent to 4 log₁₀IU/ml) for more than 3 months before TAC-CsA switch. We ensured 6 months of follow up after conversion, between 2020 to 2023. We calculated the slope of change for log-BKPyV-VL in log₁₀IU/ml/month using least-square method and compared the mean results before and after TAC-CsA switch.

Results

32 patients were included in the analysis. 25 (78.1%) patients had deceased kidney transplantation (KT), and 17 (53.1%) patients received anti-thymocyte globulin. Before TAC-CsA switch, 17 (53.1%) had a change of mycophenolate to leflunomide, 4 (12.5%) and 14 (43.8%) were given cidofovir and intravenous immunoglobulin, respectively. Median time from last immunosuppression adjustment/ therapy given prior to TAC-CsA switch was 112.5 (interquartile range (IQR) 225.75) days. At time of TAC-CsA switch, median BKPyV-VL was 321x10³ (IQR 2.49x10⁶) IU/ml, equivalent to median log-BKPyV-VL of 5.50 (IQR 1.39) log₁₀IU/ml. The mean slope of change for log-BKPyV-VL before and after TAC-CsA switch were 0.304 (95% confidence interval (CI) 0.139, 0.469) and -0.279 (95% CI -0.353, -0.204) log₁₀IU/ml/month respectively. Mean difference between the slopes before and after TAC-CsA switch was -0.583 (95% CI -0.807, -0.358) log₁₀IU/ml/month (p < 0.001). 21 (65.6%) patients achieved log-BKPyV-VL improvement of at least 0.2 log₁₀IU/ml/month (equivalent to 16 fold VL reduction in 6-month period) after TAC-CsA switch.

Conclusion

TAC-CsA switch is a useful strategy for difficult to treat BKPyV viremia among KTRs.