Evaluation of Conversion to Extended-Release Tacrolimus in Abdominal Organ and Thoracic Transplant Recipients
1Pharmacy, Temple University Hospital, Philadelphia, PA, 2Pharmacy, Temple University School of Pharmacy, Philadelphia, PA
Meeting: 2021 American Transplant Congress
Abstract number: 930
Keywords: Dosage, Immunosuppression, Pharmacokinetics
Topic: Clinical Science » Kidney » Kidney Immunosuppression: Novel Regimens and Drug Minimization
Session Information
Session Name: Kidney Immunosuppression: Novel Regimens and Drug Minimization
Session Type: Poster Abstract
Session Date & Time: None. Available on demand.
Location: Virtual
*Purpose: An established approach for conversion from immediate-release tacrolimus (IR TAC) to extended-release tacrolimus (LCPT) in kidney transplantation exists, but is lacking in other organ populations. Due to recent shortages of IR TAC, an increase in use of LCPT is seen in all organ populations. To broaden our understanding of the optimal approach in converting from IR TAC to LCPT, the purpose of this study is to identify differences in conversion ratios amongst all organ populations compared to current conversion recommendations.
*Methods: One hundred twenty-four transplant recipients were included (43 kidney, 8 kidney/pancreas, 6 liver, 17 heart, and 50 lung). The primary outcome was the conversion ratio from IR TAC to LCPT required to achieve therapeutic TAC trough levels. Secondary outcomes included pre-conversion IR TAC dosage, LCPT dosage at time of therapeutic TAC trough level, and serum creatinine (SCr) at time of therapeutic TAC trough level.
*Results: Mean age at transplantation was 59.9 + 11.8 years. A lower mean age and a higher percentage of African American and Hispanic patients were noted in the abdominal organ transplant (AOT) population compared to the thoracic transplant population. Ethnicity was self-reported. At conversion, 72% of patients were at a therapeutic TAC trough level. The mean conversion ratio at time of conversion from IR TAC to LCPT was 1:0.91 for all organ populations. At the time of achieving therapeutic TAC trough levels, the mean conversion ratio required to reach therapeutic TAC trough level was 1:0.91 with lower median conversion ratios required in thoracic transplant recipients (1:0.81 for heart and 1:0.79 for lung) compared to AOT recipients (1:1 for kidney, 1:1 for kidney/pancreas, and 1:0.95 for liver). A longer than desirable time to reach therapeutic level was noted which may be due to varying frequency in checking TAC trough levels. No notable changes in mean SCr at conversion to time to achieve therapeutic level were observed (1.46 mg/dL vs. 1.57 mg/dL).
| All Patients (N= 124) | Kidney (N= 43) | Lung (N= 50) | Heart (N= 17) | Kidney/Pancreas (N= 8) | Liver (N= 6) | |
| Age (years), mean + SD | 59.9 + 11.8 | 57.1 + 11.5 | 65.3 + 8.8 | 61.4 + 10.7 | 45.3 + 13.2 | 54.8 + 12.4 |
| Ethnicity, n (%) White; Black; Hispanic | 62 (50); 46 (37); 14 (11) | 11 (26); 22 (51); 8 (18) | 39 (78); 9 (18); 2 (0.04) | 9 (53); 7 (41); 1 (0.06) | 0 (0); 5 (63); 3 (38) | 3 (50); 3 (50); 0 (0) |
| Mean pre-conversion IR TAC daily dose (mg/day), mean + SD | 6.73 + 4.27 | 6.72 + 3.82 | 6.64 + 4.39 | 5.32 + 2.88 | 8.12 + 6.83 | 9.75 + 4.86 |
| Median initial conversion ratio (IR TAC : LCPT), mg : mg | 1 : 0.9 | 1 : 1 | 1 : 0.8 | 1 : 0.8 | 1 : 1 | 1 : 1 |
| Median conversion ratio at time of achieving therapeutic TAC trough level (IR TAC : LCPT), mg : mg | 1 : 0.89 | 1 : 1 | 1 : 0.79 | 1 : 0.81 | 1 : 1 | 1 : 0.95 |
| Mean LCPT dose, (mg/day), mean + SD At conversion; Post-conversion at therapeutic TAC trough level | 6.09 + 4.23; 5.95 + 4.06 | 6.61 + 4.45; 6.49 + 4.04 | 5.5 + 3.51; 5.29 + 3.54 | 4.5 + 2.51; 4.34 + 2.38 | 8.25 + 7.17; 8.5 + 7.11 | 9 + 5.37; 8.83 + 7.5 |
| Time to achieve therapeutic level (days), mean | 49.9 | 68.7 | 24.3 | 55.8 | 54.3 | 108.1 |
*Conclusions: Our findings suggest that different dosing conversion requirements may be warranted depending on the type of organ transplant received. A higher percentage of African American and Hispanic patients in the AOT population may have led to higher dosing requirements of LCPT in this cohort. Organ type, age, and ethnicity should be taken into consideration when determining conversion ratios from IR TAC to LCPT. Further prospective research is needed to confirm these findings.
To cite this abstract in AMA style:
Diamond A, Agarwal N, Younas A, Sifontis N, Au J, Ruggia-Check C. Evaluation of Conversion to Extended-Release Tacrolimus in Abdominal Organ and Thoracic Transplant Recipients [abstract]. Am J Transplant. 2021; 21 (suppl 3). https://atcmeetingabstracts.com/abstract/evaluation-of-conversion-to-extended-release-tacrolimus-in-abdominal-organ-and-thoracic-transplant-recipients/. Accessed June 23, 2025.« Back to 2021 American Transplant Congress