P-35 An observational study of health-related quality of life (HRQoL) with electronic patient-reported outcome (ePRO) monitoring during nivolumab therapy for advanced gastric cancer as the 3rd or later line treatment: NIVO-G QoL study

Abstract

Nivolumab is the first immune checkpoint inhibitor that proves efficacy in advanced gastric or gastroesophageal junction cancer and is approved as the 3rd or later line treatment. However, the patients (pts)'s HRQoL has not been evaluated in this setting. We thus investigated how adverse events (AEs) affect HRQoL decline during nivolumab treatment and assessed the feasibility of symptom monitoring at home using the patient’s own smartphone. Eligible pts were aged ≧20 years with ECOG-PS of 0-2, diagnosed as advanced gastric cancer, and were scheduled to receive nivolumab every two weeks as the 3rd or later line treatment. Pts assessed symptomatic AEs by themselves with PRO-CTCAE and HRQoL with FACT-Ga weekly through ePRO system using pts’ own smartphones or rental devices. Objective AEs were evaluated with NCI-CTCAE v5 at the time of consultation. The observation period was 12 weeks. The primary endpoint was the association between each AE and HRQoL decline. The impact of AE deterioration on HRQoL decline was determined by the longitudinal data analysis using a general linear model. The response variable was FACT-Ga total score changes from baseline for each time point. Explanatory variables were FACT-Ga total score at baseline, time point, and composite grade of each AE based on PRO-CTCAE. After ePRO monitoring, the pts completed the questionnaire about its usability. Between April 2019 and April 2020, 30 pts were enrolled, out of which 29 were evaluable. Twenty pts had completed ePRO monitoring by the end of the observation period, of which 10 pts had still continued nivolumab. The median age of pts was 71 years, and 58% were male. 97% of the pts were PS 0-1 and treated after the third line of treatment. 37.9% of pts do not use their smartphones on a regular basis, and 52.4% were aware of the difficulty of using them. As a result, only 0.95% of the total timepoints were missing data due to no ePRO input, indicating good compliance. The median time until the definitive deterioration of the FACT-Ga total score was nine weeks (95%CI: 3-NA). AEs such as stomatitis (p<0.0001), dysgeusia (p<0.0001), pain (p<0.0001, malaise (p<0.0001, nausea (p=0.0006, depression (p=0.0011, insomnia (p=0.0035), loss of appetite (p=0.0047, shortness of breath (p=0.0052, and vomiting (p=0.0123) were associated with worsening HRQoL, but peripheral neuropathy, diarrhea, and constipation were not. For the questionnaire about the usability of ePRO, no pts answered “not satisfied”, but only 33.4% of pts were answered “satisfied”. While 33.4% of pts wanted to continue using ePRO, 22.2% did not. Symptom monitoring with ePRO revealed that certain AEs may be responsible for the decrease in HRQoL in pts with advanced gastric cancer during the 3rd or later line nivolumab treatment. Although compliance in the ePRO input was sufficient, there are still challenges in implementing it in daily practice to meet pts expectations.