1066P - Potential effects of olanzapine: Enhancing the immune response to PD-1/PD-L1 inhibitors

Background

Immunotherapy (at present, it is mainly the use of immune checkpoint inhibitors such as PD-1/PD-L1 inhibitors) has become the fourth pillar of tumor treatment after surgery, chemotherapy and radiotherapy, but only about 20% of people benefit from it. In recent years, it has been shown that psychological stress can lead to poorer immunotherapy outcomes. Thus whether the use of antipsychotics can influence the efficacy of immunotherapy is a question worth exploring. Olanzapine, an atypical benzodiazepine antipsychotic, has traditionally been used to improve patients' moods. It is also effective in relieving adverse effects such as chemotherapy-related nausea and vomiting (CINV) and loss of appetite in tumor patients.

Methods

This study retrospectively analyzed tumor patients using PD-1/PD-L1 inhibitors at the Second Affiliated Hospital of Nanchang University in China from 2017-2022 (n=1933), with 99 patients using olanzapine and 1,834 patients not using it. Patients using olanzapine after removal by exclusion criteria served as the experimental group (n=46), and patients not using olanzapine after PSM (1:1 propensity score matching) served as the control group (n=46). Rurvival between the two groups of patients was analyzed.

Results

Olanzapine use was associated with better immune outcomes. Compared to patients not using olanzapine, patients taking olanzapine (HR=2.599,95%CI:1.423 to 4.748, p=0.002) had better objective remission rate (ORR), performance (21.73% vs 36.95%), and longer median overall survival (OS; 10 months vs 70 months, p=0.001).

Conclusions

This study suggests that the use of olanzapine may improve the overall survival of patients treated with PD-1/PD-L1 inhibitors, showing better immune response power.

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.