Teclistamab-Cqyv side effects: what 2,117 FDA adverse event reports show
Drug class
Bispecific b-cell maturation antigen (bcma)-directed cd3 t-cell engager
Brand names
Tecvayli
Who reports
2,117 reports · 82% serious · 421 with death outcome · 47% female
Used for
TECVAYLI is indicated for the treatment of adult patients with relapsed or refractory multiple myeloma in combination with daratumumab and hyaluronidase-fihj in patients who have received at least one prior line of therapy, including a proteasome inhibitor and an immunomodulatory agent.
What it is
Teclistamab-cqyv, a bispecific B-cell maturation antigen (BCMA)-directed CD3 T-cell engager, is a humanized immunoglobulin G4-proline, alanine, alanine (IgG4-PAA) antibody. Teclistamab-cqyv is produced in Chinese Hamster Ovary (CHO) cells using recombinant DNA technology.
Boxed warning
CYTOKINE RELEASE SYNDROME and NEUROLOGIC TOXICITY, including IMMUNE EFFECTOR CELL-ASSOCIATED NEUROTOXICITY SYNDROME Cytokine release syndrome (CRS), including life-threatening or fatal reactions, can occur in patients receiving TECVAYLI. Initiate treatment with TECVAYLI step-up dosing schedule to reduce risk of CRS.
Causality screen of the 23 strongest signals
What the badges mean
- Labeled — boxed warning The term (or its clinical synonym) appears in the FDA boxed warning: causality is regulator-recognised and considered serious.
- Labeled adverse reaction The exact term appears in the label's warnings or adverse-reactions sections: a known, expected effect. The FAERS signal confirms the label rather than discovering anything.
- Labeled (related wording) The label describes this effect under different wording (e.g. 'neutropenia' for 'neutrophil count decreased'). Treated as known.
- Likely indication confounding The term appears in the label's indications: reports probably describe the disease being treated (or its progression), not a drug effect. Classic confounding by indication.
- Reporting / coding artifact An administrative, monitoring or exposure term (product issue, off-label use, 'test normal', overdose...). Not a biological reaction; a high PRR here reflects how reports are coded.
- Not in label — unassessed Not found in the label text, not an artifact pattern. This is a genuine candidate for a formal causality assessment (Bradford Hill / WHO-UMC); it has NOT had one here.
Strongest disproportionality signals
Flagged terms (PRR ≥ 2, χ² ≥ 4, n ≥ 10), ranked by PRR; infinite PRRs (no comparator reports) excluded. The EBGM column is a second, shrinkage-based estimate (MGPS) with its 5th percentile EB05 and the BCPNN IC025; a pair flagged by PRR alone is marked PRR-only and should be read as fragile. The strata column recomputes the PRR on serious reports only and flags pairs whose reports are unusually skewed by sex or come mostly from consumers rather than clinicians. 19 further terms are in the interactive explorer. Reaction links open the term's cross-drug page.
| Reaction | Reports | PRR 95% CI · ROR · χ²/p | EBGM EB05 · IC025 | Label screen | Serious-only & strata | Trial cross-check |
|---|---|---|---|---|---|---|
| Cytokine release syndrome | 508 | 271.1 251.0–292.9ROR 356.3 · χ² 132,876 / p <1e-300 | 261.2 EB05 242.7 · IC025 +7.6 3/3 methods agree | Labeled — boxed warning exact term | serious PRR 185.6 · 91% clinician | no trial data cached |
| Plasma cell myeloma | 123 | 31.2 26.3–37.1ROR 33.1 · χ² 3,564 / p <1e-300 | 31.0 EB05 26.7 · IC025 +4.5 3/3 methods agree | Likely indication confounding shares a disease stem with the indications wording | serious PRR 23.6 · 91% clinician | no trial data cached |
| Cytopenia | 32 | 26.6 18.8–37.5ROR 27.0 · χ² 760 / p 1e-167 | 26.1 EB05 19.4 · IC025 +3.7 3/3 methods agree | Labeled adverse reaction exact term | serious PRR 19.2 · 94% clinician | no trial data cached |
| Adverse reaction | 27 | 20.2 13.9–29.4ROR 20.4 · χ² 472 / p 5e-105 | 19.9 EB05 14.3 · IC025 +3.3 3/3 methods agree | Reporting / coding artifact | serious n=26 · 93% clinician | no trial data cached |
| Neurotoxicity | 32 | 18.3 12.9–25.8ROR 18.5 · χ² 504 / p 6e-112 | 18.0 EB05 13.3 · IC025 +3.3 3/3 methods agree | Labeled — boxed warning exact term | serious PRR 12.9 · 91% clinician | no trial data cached |
| Respiratory tract infection | 36 | 13.7 9.9–19.0ROR 14.0 · χ² 412 / p 5e-92 | 13.4 EB05 9.9 · IC025 +3.0 3/3 methods agree | Labeled adverse reaction exact term | serious PRR 10.5 · ♀ 88% (drug 47%) · 94% clinician | no trial data cached |
| Clostridium difficile colitis | 12 | 11.2 6.4–19.7ROR 11.3 · χ² 101 / p 4e-24 | 9.5 EB05 5.2 · IC025 +2.0 3/3 methods agree | Not in label — unassessed | serious PRR 8.0 | no trial data cached |
| Cytomegalovirus infection | 17 | 10.1 6.3–16.3ROR 10.2 · χ² 131 / p 1e-30 | 8.9 EB05 5.6 · IC025 +2.2 3/3 methods agree | Labeled (related wording) related wording | serious PRR 5.9 | no trial data cached |
| Bacteraemia | 12 | 10.1 5.7–17.8ROR 10.1 · χ² 89 / p 2e-21 | 8.3 EB05 4.7 · IC025 +1.9 3/3 methods agree | Not in label — unassessed | serious PRR 7.1 | no trial data cached |
| Covid-19 pneumonia | 11 | 9.2 5.1–16.5ROR 9.2 · χ² 72 / p 1e-17 | 7.3 EB05 4.1 · IC025 +1.7 3/3 methods agree | Labeled (related wording) related wording | serious PRR 6.5 | no trial data cached |
| Infection | 112 | 7.7 6.4–9.2ROR 8.1 · χ² 649 / p 2e-143 | 7.5 EB05 6.4 · IC025 +2.6 3/3 methods agree | Labeled — boxed warning exact term | serious PRR 5.9 · 95% clinician | no trial data cached |
| Colitis | 26 | 6.8 4.7–10.0ROR 6.9 · χ² 124 / p 5e-29 | 6.2 EB05 4.4 · IC025 +2.0 3/3 methods agree | Not in label — unassessed | serious PRR 5.2 | no trial data cached |
| Neutropenia (low neutrophils (infection-fighting cells)) | 93 | 6.8 5.6–8.3ROR 7.1 · χ² 457 / p 1e-101 | 6.6 EB05 5.5 · IC025 +2.4 3/3 methods agree | Labeled — boxed warning exact term | serious PRR 4.9 · 92% clinician | no trial data cached |
| Product prescribing issue | 12 | 5.8 3.3–10.3ROR 5.9 · χ² 43 / p 2e-11 | 4.9 EB05 3.0 · IC025 +1.3 3/3 methods agree | Reporting / coding artifact | – | no trial data cached |
| Septic shock | 25 | 5.7 3.9–8.5ROR 5.8 · χ² 93 / p 3e-22 | 5.2 EB05 3.7 · IC025 +1.7 3/3 methods agree | Labeled adverse reaction exact term | serious PRR 4.0 · 96% clinician | no trial data cached |
| Injection site rash | 17 | 5.5 3.5–8.9ROR 5.6 · χ² 59 / p 8e-15 | 4.9 EB05 3.2 · IC025 +1.5 3/3 methods agree | Labeled (related wording) related wording | serious n=11 | no trial data cached |
| Clostridium difficile infection | 10 | 4.6 2.5–8.5ROR 4.6 · χ² 24 / p 4e-7 | 3.9 EB05 2.3 · IC025 +0.9 3/3 methods agree | Not in label — unassessed | serious PRR 3.4 | no trial data cached |
| Covid-19 | 79 | 4.4 3.6–5.5ROR 4.6 · χ² 207 / p 3e-47 | 4.3 EB05 3.6 · IC025 +1.7 3/3 methods agree | Labeled adverse reaction exact term | serious PRR 5.1 | no trial data cached |
| Neutrophil count decreased | 18 | 4.4 2.8–7.0ROR 4.4 · χ² 44 / p 2e-11 | 4.0 EB05 2.7 · IC025 +1.2 3/3 methods agree | Labeled — boxed warning synonym match | serious PRR 3.6 | no trial data cached |
| Bone pain | 25 | 4.2 2.9–6.2ROR 4.3 · χ² 58 / p 1e-14 | 3.9 EB05 2.8 · IC025 +1.3 3/3 methods agree | Labeled adverse reaction exact term | serious PRR 3.8 | no trial data cached |
| Injection site reaction | 24 | 3.5 2.3–5.2ROR 3.5 · χ² 40 / p 1e-10 | 3.3 EB05 2.3 · IC025 +1.0 3/3 methods agree | Labeled adverse reaction exact term | serious PRR 6.8 | no trial data cached |
| Adverse event | 30 | 3.2 2.3–4.6ROR 3.3 · χ² 44 / p 2e-11 | 3.1 EB05 2.3 · IC025 +1.0 3/3 methods agree | Reporting / coding artifact | serious PRR 3.4 | no trial data cached |
| Myelosuppression | 11 | 3.2 1.8–5.8ROR 3.2 · χ² 15 / p 7e-5 | 2.9 EB05 1.8 · IC025 +0.5 | Not in label — unassessed | serious PRR 2.2 | no trial data cached |
Trial evidence (ClinicalTrials.gov)
Most frequently reported reactions
By raw co-report count, regardless of disproportionality. Common terms here are often the illness itself or generic outcomes.
| Reaction | Reports | PRR 95% CI · ROR · χ²/p | EBGM EB05 · IC025 | Label screen | Serious-only & strata | Trial cross-check |
|---|---|---|---|---|---|---|
| Cytokine release syndrome | 508 | 271.1 251.0–292.9ROR 356.3 · χ² 132,876 / p <1e-300 | 261.2 EB05 242.7 · IC025 +7.6 3/3 methods agree | Labeled — boxed warning exact term | serious PRR 185.6 · 91% clinician | no trial data cached |
| Plasma cell myeloma | 123 | 31.2 26.3–37.1ROR 33.1 · χ² 3,564 / p <1e-300 | 31.0 EB05 26.7 · IC025 +4.5 3/3 methods agree | Likely indication confounding shares a disease stem with the indications wording | serious PRR 23.6 · 91% clinician | no trial data cached |
| Infection | 112 | 7.7 6.4–9.2ROR 8.1 · χ² 649 / p 2e-143 | 7.5 EB05 6.4 · IC025 +2.6 3/3 methods agree | Labeled — boxed warning exact term | serious PRR 5.9 · 95% clinician | no trial data cached |
| Neutropenia (low neutrophils (infection-fighting cells)) | 93 | 6.8 5.6–8.3ROR 7.1 · χ² 457 / p 1e-101 | 6.6 EB05 5.5 · IC025 +2.4 3/3 methods agree | Labeled — boxed warning exact term | serious PRR 4.9 · 92% clinician | no trial data cached |
| Covid-19 | 79 | 4.4 3.6–5.5ROR 4.6 · χ² 207 / p 3e-47 | 4.3 EB05 3.6 · IC025 +1.7 3/3 methods agree | Labeled adverse reaction exact term | serious PRR 5.1 | no trial data cached |
| Respiratory tract infection | 36 | 13.7 9.9–19.0ROR 14.0 · χ² 412 / p 5e-92 | 13.4 EB05 9.9 · IC025 +3.0 3/3 methods agree | Labeled adverse reaction exact term | serious PRR 10.5 · ♀ 88% (drug 47%) · 94% clinician | no trial data cached |
| Neurotoxicity | 32 | 18.3 12.9–25.8ROR 18.5 · χ² 504 / p 6e-112 | 18.0 EB05 13.3 · IC025 +3.3 3/3 methods agree | Labeled — boxed warning exact term | serious PRR 12.9 · 91% clinician | no trial data cached |
| Cytopenia | 32 | 26.6 18.8–37.5ROR 27.0 · χ² 760 / p 1e-167 | 26.1 EB05 19.4 · IC025 +3.7 3/3 methods agree | Labeled adverse reaction exact term | serious PRR 19.2 · 94% clinician | no trial data cached |
| Adverse event | 30 | 3.2 2.3–4.6ROR 3.3 · χ² 44 / p 2e-11 | 3.1 EB05 2.3 · IC025 +1.0 3/3 methods agree | Reporting / coding artifact | serious PRR 3.4 | no trial data cached |
| Adverse reaction | 27 | 20.2 13.9–29.4ROR 20.4 · χ² 472 / p 5e-105 | 19.9 EB05 14.3 · IC025 +3.3 3/3 methods agree | Reporting / coding artifact | serious n=26 · 93% clinician | no trial data cached |
| Colitis | 26 | 6.8 4.7–10.0ROR 6.9 · χ² 124 / p 5e-29 | 6.2 EB05 4.4 · IC025 +2.0 3/3 methods agree | Not in label — unassessed | serious PRR 5.2 | no trial data cached |
| Bone pain | 25 | 4.2 2.9–6.2ROR 4.3 · χ² 58 / p 1e-14 | 3.9 EB05 2.8 · IC025 +1.3 3/3 methods agree | Labeled adverse reaction exact term | serious PRR 3.8 | no trial data cached |
| Septic shock | 25 | 5.7 3.9–8.5ROR 5.8 · χ² 93 / p 3e-22 | 5.2 EB05 3.7 · IC025 +1.7 3/3 methods agree | Labeled adverse reaction exact term | serious PRR 4.0 · 96% clinician | no trial data cached |
| Injection site reaction | 24 | 3.5 2.3–5.2ROR 3.5 · χ² 40 / p 1e-10 | 3.3 EB05 2.3 · IC025 +1.0 3/3 methods agree | Labeled adverse reaction exact term | serious PRR 6.8 | no trial data cached |
| Injection site erythema (redness where injected) | 19 | 1.5 1.0–2.4ROR 1.5 · χ² 3 / p 0.044 | 1.5 EB05 1.0 · IC025 -0.2 PRR-only: not supported by EBGM or IC | Labeled (related wording) related wording | serious PRR 3.8 | no trial data cached |
Unlabeled candidate signals
These flagged terms were not found in the FDA label text and do not match an artifact pattern. They are the pairs that would merit a structured assessment (temporality, dose-response, biological plausibility, consistency across databases, trial or cohort evidence). The screen has not done that; string-matching misses label wording, and a strong PRR can still be stimulated reporting, co-medication, or the disease itself.
- Colitis — n=26, PRR 6.8
Want to assess one of these properly? The runbook describes the Bradford Hill / trial-evidence workflow used on the assessment page, and handoff_top1000_signals.csv lists the strongest unassessed pairs across all drugs.
Common questions
What are the most reported side effects of Teclistamab-Cqyv?
In FDA FAERS, the most frequently co-reported reaction terms for Teclistamab-Cqyv are cytokine release syndrome, plasma cell myeloma, infection, neutropenia, covid-19, respiratory tract infection. These are report counts, not rates: FAERS has no denominator, reporting is voluntary and uneven, and a term can be reported because of the illness being treated rather than the drug.
Does Teclistamab-Cqyv have an FDA boxed warning?
Yes. The current FDA label carries a boxed warning: CYTOKINE RELEASE SYNDROME and NEUROLOGIC TOXICITY, including IMMUNE EFFECTOR CELL-ASSOCIATED NEUROTOXICITY SYNDROME Cytokine release syndrome (CRS), including life-threatening or fatal reactions, can occur in patients receiving TECVAYLI. Initiate treatment with TECVAYLI step-up dosing schedule to reduce risk of CRS.
Do FAERS signals prove that Teclistamab-Cqyv causes these side effects?
No. A disproportionality signal (PRR, ROR) means a reaction is reported more often with this drug than with others in the database. That can reflect a real effect, but also the disease being treated, stimulated reporting after news or litigation, co-medications, or how reports are coded. Causality needs temporality, dose-response, biological plausibility, consistency across data sources and, ideally, trial or cohort evidence. This page screens each term against the FDA label and ClinicalTrials.gov results; it does not establish causation.
Sources & methods
- FDA label via openFDA (set ID 54e0f974-ccee-44ea-9254-40e9883cee1e, effective 20260310; matched on
openfda.generic_name.exact:"TECLISTAMAB-CQYV") - Bayesian shrinkage measures computed offline over all 1,317,300 cached pairs: BCPNN information component (IC, with Norén closed-form IC025) and MGPS empirical-Bayes geometric mean (EBGM, EB05) with a two-component gamma prior fitted by maximum marginal likelihood (α₁=0.57, β₁=0.02, α₂=1.42, β₂=0.70, w=0.17); unstratified
- FAERS pair statistics from the OpenPV build of 2026-09-14 (openFDA
count=aggregation, fieldpatient.drug.openfda.generic_name.exact, 42 reaction terms, min 3 co-reports); PRR/ROR with 95% CI, chi-square with Yates correction - Serious-only and stratified counts (serious:1, patient.patientsex, primarysource.qualification) from openFDA count queries; serious-only PRR uses the drug serious report total and the term global serious total (N_serious=11,882,979); strata shown only when n ≥ 20
- Seriousness and sex counts from openFDA
count=serious,patient.patientsex,seriousnessdeath
Page generated 2026-10-08. Label and PubChem text are retrieved automatically and may lag the current label; always check the current prescribing information. OpenPV is a beta research tool of the Open Source Medicine Foundation.