Letermovir prophylaxis falls short of reducing medication regimen complexity index (MRCI) over time in patients who underwent allogeneic haematopoietic stem cell transplantation (allo-HCT), according to a study.
“[O]ur study confirms a high medication burden among allo-HCT recipients, with notable increases in MRCI scores from admission to discharge and throughout the first-year post-transplant,” the researchers said. “These findings emphasize the need for proactive interventions to reduce medication regimen complexity in this vulnerable patient population.”
A total of 218 adults who underwent allo-HCT from 1 January 2016 to 31 October 2021 were included in this retrospective analysis. The researchers calculated MRCI scores at admission, discharge, day 100, 6 months, and 1-year post-transplant.
Of the patients, 67 received letermovir and 151 did not. The median MRCI scores were comparable at discharge after allo-HCT (23 vs 22; p=0.97), but at day 100, patients treated with letermovir showed significantly higher median scores than those who did not receive the study drug (59 vs 50; p=0.009). [J Oncol Pharm Pract 2026;32:973-978]
At 1 year following allo-HCT, MRCI scores did not significantly differ between groups (47 vs 41; p=0.12).
“Contrary to our hypothesis, the use of letermovir prophylaxis did not result in a decrease in medication regimen complexity over time,” the researchers said.
Complex regimens
“When comparing our MRCI findings to other patient populations, it becomes apparent that allo-HCT recipients require incredibly complex medication regimens,” they said.
For instance, an earlier study involving patients with advanced chronic conditions requiring palliative care reported a mean MRCI score of 38. In another study, a cohort of patients with end-stage renal disease showed a mean MRCI score of 42.3 in the first month after kidney transplant. [Eur J Hosp Pharm 2019;26:262-267; Kidney Int Rep 2020;6:128-137]
Furthermore, older adults with heart failure, adult patients with HIV, and adult patients with diabetes had lower mean MRCI scores (32, 21.8, and 23.0, respectively). [Clin Ther 2013;35:385-398.e1]
“In contrast, median MRCI scores immediately after allo-HCT in both study groups exceeded 45,” the researchers said. “This further underscores the substantial medication burden faced by allo-HCT recipients.”
Medication adherence
The current study did not examine medication adherence, making it difficult to determine the clinical implications of these MRCI scores or their association with nonadherence. However, previous studies found an association between MRCI and increased nonadherence, resulting in poorer clinical outcomes. [PLoS One 2021;16:e0252944; BMJ Open Diabetes Res Care 2019;7:e000685]
“Pharmacists can play a crucial role in reducing medication burden for these patients through their involvement in medication management and transitions of care,” the researchers said.
“Existing evidence already supports the value of pharmacists as part of a multidisciplinary HCT team, and incorporating MRCI as an additional measure can further validate their importance,” they added. [Biol Blood Marrow Transplant 2018;24:914-922]
“Future research considering potential confounding factors is needed to fully understand its impact,” the researchers said. “Our findings lay the groundwork for future investigations into the relationship between MRCI and clinical outcomes in this population.”
MRCI is used to describe the intricacy of medication regimens in patients deemed to have high medication burden. This tool considers several factors, including the number of medications, dosage forms, frequency of dosing, and additional administration instructions to generate a score summarizing the complexity of a patient’s medication regimen. [Ann Pharmacother 2004;38:1369-1376]
A high MRCI score suggests greater complexity and is associated with higher medication nonadherence, hospital readmissions, and health resource utilization. These clinical outcomes may compromise patient safety and add to economic burden. [Eur J Clin Pharmacol 2017;73:1475-1489; Ann Pharmacother 2018; 52:1117-1134; Ann Pharmacother 2018;52:862-867]