Login to Access Video or Poster Abstract: MP57-06
Sources of Funding: none

Introduction

The clinical benefit of enzalutamide for castration-resistant prostate cancer (CRPC) is its high efficacy and favorable safety profile. Subjective symptoms such as fatigue and appetite loss, which are common adverse effects (AEs) for enzalutamide, tend to be underestimated in clinical trials and may lead discontinuation of enzalutamide.  Recently, attention has been directed at  patient reported outcomes (PROs) as self-administrated assessment in the health-related quality of life (HRQoL) evaluation of cancer patients. The identification of PROs by questionnaires for subjective AEs are important in the clinical practice for their impact on HRQoL and may be different from doctor reported outcomes (DROs).

Methods

Fifty-eight CRPC patients (39 pre and 19 post docetaxel) treated with enzalutamide were assessed by PROs for subjective AEs at the time of the medical visit.

Results

Although 44 and 40 of 58 patients reported fatigue and appetite loss by PRO, only 32 and 24 patients had G1 or over fatigue and appetite loss by doctor reported outcomes (DROs) (Table. 1). Eighteen patients needed the dose reduction or interruption by fatigue or appetite loss and 14 of 18 patients, their subjective symptoms were improved quickly and they can continue to take without AEs (Fig. 1). Surprisingly, the patients who needed the dose reduction of enzalutamide had longer time to treatment failure (Fig.2).

Conclusions

The DROs assessment of subjective AEs of enzalutamide differed from the PRO assessment. The prompt dose reduction of enzalutamide in response to the PRO assessment improved the symptoms and prevented dropping out due to AEs. PRO assessment is a useful tool to rapidly identify AEs which can lead to prompt dose modification,  decreased patient drop out  and improved outcomes to Enzalutamide treatment.

Funding

none