Lenalidomide will be administered orally

Overall Survival (OS), measured from the date of from randomization to the date the subject's death

The EORTC QLQ-C30 is a 30-item questionnaire containing both single and multi-item measures. These include five functional scales (Physical, Role, Cognitive, Emotional, and Social Functioning), three symptom scales (Fatigue, Pain, and Nausea/Vomiting), a Global Health Status/ Quality-of-Life (QoL) scale, and six single items (Constipation, Diarrhea, Insomnia, Dyspnea, Appetite Loss, and Financial Difficulties). The scores ranges from 0-100, a high score for functional scales and for Global Health Status/QoL represent better functioning ability or Health-Related Quality-of-Life (HRQoL), whereas a high score for symptom scales and single items represents significant symptomatology.

The EQ-5D-5L is a 5 item questionnaire that assesses 5 domains including mobility, self care, usual activities, pain/discomfort, and anxiety/depression plus a visual analog scale rating "health today"

The MySIm-Q is a disease-specific PRO assessment complementary to the EORTC-QLQ-C30. It includes 17 items resulting in a symptom subscale and an impact subscale. The recall period is the "past 7 days", and responses are reported on a 5-point verbal rating scale.

The PRO-CTCAE Measurement System characterizes the frequency, severity, interference, and presence/absence of symptomatic toxicities. The PRO-CTCAE Item Library includes 124 items representing 78 symptomatic toxicities drawn from the CTCAE

PGIS is a 1 item questionnaire that evaluates patients' health and assesses if there has been an improvement or decline in clinical status