1844P - 3-year experience of the Belgian multidisciplinary immunotoxicity board (BITOX): A nationwide initiative of the Belgian Society of Medical Oncology (BSMO)

Background

With the increasing use of immune-checkpoint inhibitors (ICIs), immune-related adverse events (irAEs) are increasingly prevalent. The common exclusion of patients with dysimmune comorbidities from trials as well as the lack of long-term data on managing irAEs, make multidisciplinary collaboration on these highly variable and sometimes life-threatening toxicities essential. BITOX was founded in 2021 to share experiences and identify clinically relevant research questions and is the only national toxicity board to date.

Methods

BITOX is a biweekly virtual meeting between Belgian oncologists and organ specialists. Healthcare providers submit questions regarding diagnosis, management, and ICI safety in dysimmune patients via an electronic REDCap form, enhancing accessibility for physicians and facilitating registry establishment. In addition to the live discussion, a written advice is communicated to the submitter within 2 days. A retrospective analysis of the discussed cases was conducted.

Results

From March 2021 to March 2024, 246 submissions from 131 physicians have been discussed. Neurological (n=35; 14,4%) and rheumatological toxicity (n=32; 13,2%) were the most frequent irAEs discussed, with diagnostic questions prevailing in the first, and management questions in the latter category. Most patients were on anti-PD-1 monotherapy (n=111; 51.4%) and had dysimmune comorbidities (n=162; 65.9%). Regarding irAE management, escalation of immunosuppression was recommended in 26% of cases, whereas de-escalation was suggested in 51,8% of cases that were on multiple immunosuppressants prior to referral. To extend the reach of BITOX, multiple presentations were done, resulting in quarterly rises in submissions from physicians across all Belgian regions. Every physician submitted on average 1,85 cases.

Conclusions

The establishment of a national, virtual, multidisciplinary immunotoxicity board is shown to be feasible. It enhances multidisciplinary discussion of ICI-related problems in Belgium. Furthermore, the discussions highlighted lingering uncertainties regarding neurological and rheumatological irAEs, indicating the necessity for further research.

Clinical trial identification

Editorial acknowledgement

Legal entity responsible for the study

The authors.

Funding

BMS, MSD, Pfizer, Merck, Roche, AstraZeneca, Ipsen and Sanofi. Sponsorship paid to Belgian Society of Medical Oncology.

Disclosure

M. Verhaert: Non-Financial Interests, Institutional, Member of Board of Directors: BITOX; Financial Interests, Institutional, Speaker, Consultant, Advisor: Ipsen, MSD, Roche, Domus Medica, Pfizer, Jansen; Financial Interests, Personal, Research Grant, Registration number 1SH4A24N: Research Foundation Flanders. S. Aspeslagh: Financial Interests, Institutional, Advisory Board: MSD, Sanofi, Roche, BMS, Pfizer, Ipsen, Galapagos, Astellas. All other authors have declared no conflicts of interest.