1055P - Analysis of correlation between quality of life (QoL) results and survival outcomes in phase III clinical trials testing immunotherapy in metastatic cancers

Background

Multiple trials revealed that immunotherapy (IO) improved survival endpoints in several metastatic solid tumors. However, concomitant benefit in QoL outcomes has been less explored. Herein, we examined QoL results in phase III randomized controlled trials (RCTs) investigating IO in metastatic cancers and their correlation with OS and PFS outcomes.

Methods

We conducted a systematic review to search for articles of RCTs testing IO published in PubMed-indexed journals up to 12/2023. Only trials assessing IO in metastatic setting, reporting QoL results in primary or secondary publications and at least one survival outcome between OS and PFS were selected for analysis. For each RCT, we evaluated whether global QoL was “superior,” “inferior,” or with “non-statistically significant difference” in the experimental arm compared to the control arm. Also, we assessed whether OS and PFS were improved or not by experimental treatment. Fisher’s exact test was used for statistical analysis.

Results

Only 71 out of 140 identified RCTs (50.7%) respected selection criteria. Superior or inferior global QoL in experimental arm was found in 30/71 (42.3%) and 1/71 (1.4%) RCTs, respectively. No statistically significant difference between study arms was observed in the remaining 40/71 (56.3%) RCTs. Of note, we found a statistically significant association between QoL and OS improvements (p=0.0045). More in detail, this association was significant in trials testing IO alone (p=0.0097). Instead, QoL results did not positively correlate with PFS outcomes (p=0.46). Next, we found that experimental treatments led to superior QoL only in 30/59 (50.8%) trials with positive results and in 1/12 (8.3%) RCTs with negative results (p = 0.0090). Interestingly, 29/59 (49.2%) positive RCTs did not lead to QoL improvements.

Conclusions

Our study reveals a positive association of QoL results with OS outcomes in RCTs testing IO in metastatic cancers, particularly for trials testing IO alone. About half of positive trials, potentially leading to new drug approval, did not prompt QoL amelioration. These findings further emphasize the relevance of an accurate assessment of QoL in oncology clinical trials.

Clinical trial identification

Editorial acknowledgement

Legal entity responsible for the study

The authors.

Funding

Has not received any funding.

Disclosure

All authors have declared no conflicts of interest.