# High Implementation Adherence to Lenalidomide in Multiple Myeloma

## TL;DR

Most multiple myeloma patients take lenalidomide as prescribed, but older patients and those without support may need extra help to stay on track.

## Contribution

This study provides novel real-world data on lenalidomide adherence using electronic monitoring in multiple myeloma patients.

## Key findings

- 75% of patients perfectly adhered to the 21/7-day lenalidomide on/off cycle.
- Only 4% of patients had dose adherence below 90%.
- Older age and lack of support were linked to lower adherence.

## Abstract

Taking oral cancer medicines exactly as prescribed is important because it directly affects how well patients do. Lenalidomide is a common oral treatment for people with multiple myeloma, given in cycles of three weeks on the drug and one week off. However, little is known about how closely patients follow this schedule in real life. In this study, we used electronic devices that record when each pill is taken to carefully track how patients used lenalidomide over time. We found that most patients followed their treatment plan very well, with many taking all of their prescribed doses correctly. Older age and lack of support were linked to lower adherence. These findings suggest that most patients are able to take lenalidomide as prescribed, but extra attention may be helpful for older patients or those without support. This information can guide doctors in improving treatment outcomes.

Background and Purpose: Adherence to oral anticancer therapy correlates with outcome. Lenalidomide (LEN) is an oral mainstay treatment for multiple myeloma (MM), administered in 21-day/7-day (on/off) cycles. Data on LEN adherence is limited. Electronic monitoring (EM) represents the most reliable adherence assessment method. Experimental Approach: We conducted a prospective observational study using electronic medication event monitoring (MEMS®) in lenalidomide-naïve multiple myeloma patients to quantify adherence during on/off cycles and identify patterns of non-adherence in real-world practice. On and off cycles were determined semi-automatically. Implementation adherence was calculated as the proportion of prescribed drug taken, during each on cycle and across all on cycles. Daily adherence predictors were analyzed using logistic regression with generalized estimating equations. Key Results: Eighty-five patients were included. Median age was 68 years, 66% received LEN as a second-line treatment, 75% of patients perfectly adhered to the recommended 21/7-day on/off cycle. Median implementation adherence was 100%. Only 4% of patients had a proportion of doses taken below 90%. All doses were taken by 51% of patients, while 9% missed ≥4 doses. Among the 13 predictors investigated, only age under 80 and participation in a support group were statistically significant. Conclusions: this novel assessment of LEN adherence in MM patients demonstrated high implementation adherence and cycle duration compliance.