Bispecific antibodies differ in their non-relapse mortality, driven largely by infection

Design

Systematic review and meta-analysis plus FAERS pharmacovigilance analysis

Population

Patients with relapsed or refractory myeloma or lymphoma on licensed bispecific antibodies

Primary outcome

Non-relapse mortality; secondary CRS, ICANS, infection and death

Effect

Highest toxicity and NRM signals with teclistamab and glofitamab; lowest with mosunetuzumab

A systematic review and meta-analysis of trial data, paired with an analysis of the US FDA Adverse Event Reporting System, compared non-relapse mortality — death from anything other than the cancer — across T-cell-engaging bispecific antibodies licensed for relapsed myeloma and lymphoma.

Teclistamab carried the heaviest burden in both sources: the most neurotoxicity (ICANS), more grade 3 or worse infections, and a non-negligible non-relapse mortality. Glofitamab had raised reporting odds for non-relapse and overall death. Mosunetuzumab showed lower toxicity estimates across both methods.

The mechanism is predictable: indefinite dosing with neutropenia, B-cell aplasia and low immunoglobulins leaves patients exposed to infection for as long as treatment continues. Pharmacovigilance reporting odds cannot give true incidence, and the products are used in different populations, so these are signals rather than head-to-head comparisons.

• Check immunoglobulin levels regularly in patients on bispecific antibodies and consider replacement when low
• Use antimicrobial prophylaxis as recommended for each product
• Monitor for neurotoxicity particularly early with teclistamab
• Treat fever on bispecifics as possible serious infection, not only cytokine release
• Discuss treatment duration — toxicity accumulates with indefinite dosing

Why it matters

Toxicity from these drugs accumulates for as long as they are given, which most protocols leave open-ended.

Don't overread it

FAERS reporting odds are signals, not incidence, and products were used in different populations; this is not a head-to-head comparison.

The statistics, in plain English

A reporting odds ratio compares how often an event is reported with one drug versus others in a spontaneous reporting database; it shows disproportion, not how often the event actually happens.

Read the rest in the app

You have read your two free briefings this month. The app carries all 27 specialties, every morning, free — and this finding is waiting in it.

Get Daily Doctor — free

Scan to keep reading on your phone. No account needed to start.