Adstiladrin
nadofaragene firadenovec · IFN-alpha2b (adenovirus, intravesical)Neutralizing anti-adenovirus and anti-IFNa2b antibodies in most high-dose monkeys, persisting through observation period
Imlygic: which risks did reviewers probe?
talimogene laherparepvec · GM-CSF (oncolytic HSV-1)
Immune & cytokine safety
Lethal disseminated HSV infection in immunodeficient mice (up to 20% nude, 100% SCID); immunocompetent mice tolerated doses
“Lethal systemic viral infection was observed in up to 20% of nude mice (primarily deficient in T lymphocyte function) and 100% of SCID mice (devoid of both T and B lymphocytes).”
Biodistribution & persistence
Low-level viral DNA at injection site, blood and urine 24 h after 5th SC dose in mice; cleared by later timepoints
“Viral DNA was detected at low levels in the injection site, blood and urine at 24 hours following the administration of the 5th injection of the product.”
Modality-specific risk
HSV-1 replication-competent virus: neurotropism/latency, dissemination in immunodeficient hosts, transmission to unintended recipients
“even though ICP34.5 has been removed from the viral genome, the virus still has some affinity for nervous system tissue.”
Anti-drug antibodies: animals
Significant serum anti-HSV antibodies in treated tumour-bearing mice by day 27, similar with or without the GM-CSF gene
“Significant levels of serum HSV antibodies were seen in treated animals on day 27. Antibody levels were similar in the talimogene laherparepvec and hGM-CSF deficient talimogene laherparepvec treated groups.”
Anti-drug antibodies: patients
Anti-GM-CSF antibody response not reported in clinical trials; listed as theoretical important potential risk
“Talimogene Laherparepvec-mediated anti-GM-CSF Antibody Response is therefore considered an important potential risk in the RMP based on theoretical concerns as this event has not been reported in clinical trials.”
Same question, other gene therapies
Beqvez
fidanacogene elaparvovec · Factor IXAnti-hFIX and anti-capsid antibodies in most NHPs, rising over time, correlated with declining hFIX
Casgevy
exagamglogene autotemcel · BCL11A enhancer (CRISPR-Cas9, ex vivo HSC)In vitro innate immune (type I IFN) assay showed no activation, but FDA deemed it uninterpretable (positive control failed)
Elevidys
delandistrogene moxeparvovec · Micro-dystrophinAnti-AAV antibodies in mice; NHP: capsid/transgene T-cell responses, liver enzymes, anaphylaxis on redosing with rituximab/sirolimus
Fayuvi
rebisufligene etisparvovec · SGSH (AAV9)Immunogenicity greater against AAV9 capsid than hSGSH transgene, proportional to dose
Genglycos
pariglasgene brecaparvovec · G6PC (AAV8)Anti-AAV8 nAbs in all dosed mice and NHPs; AAV8 T-cell responses in mice; sporadic cytokine elevations; juvenile immune stimulation
Glybera
alipogene tiparvovec · LPL (AAV1)Neutralising anti-AAV1 capsid antibodies blocked readministration; no CD8+ T cells in infiltrates; no anti-LPL antibodies
Hemgenix
etranacogene dezaparvovec · Factor IXAnti-AAV5 capsid IgG persisting 6 months; anti-hFIX antibodies in 5/12 NHPs reducing FIX levels
Itvisma
onasemnogene abeparvovec (intrathecal) · SMN1 (AAV9, intrathecal)Mononuclear cell inflammation in NHP neural tissue; clinically all patients developed high anti-AAV9 titers, anti-SMN in ~7%
Kebilidi
eladocagene exuparvovec · AADCDose-dependent anti-AAV2 capsid ADA in rats; no effect on biodistribution or expression; anti-AADC not assessed
Lenmeldy
atidarsagene autotemcel · ARSA (LVV, ex vivo HSC)No anti-ARSA antibodies or adverse neurobehavioral effects in mice; anti-ARSA antibodies in 15% of patients clinically
Luxturna
voretigene neparvovec · RPE65Anti-AAV2 capsid antibodies (dogs, pre-exposed NHPs); minimal T-cell responses; mild ocular inflammation on re-administration
Otarmeni
lunsotogene parvec · OTOF (AAV, intracochlear)All monkeys anti-AAV1 NAb positive by week 27, no anti-otoferlin antibodies; NAbs not associated with safety signal; minimal cochlear infiltrates
Papzimeos
zopapogene imadenovec · HPV6/11 antigens (gorilla adenovirus)Intended HPV-specific CD8+ T-cell IFN-gamma/TNF-alpha responses; in silico screen shows low off-target human protein reactivity
Roctavian
valoctocogene roxaparvovec · Factor VIIIAnti-AAV5 antibodies in all species; anti-hFVIII antibodies cross-reacting with murine FVIII caused bleeding phenotype (species-specific)
Tudriqev
vusolimogene oderparepvec · GALV-GP + GM-CSF (oncolytic HSV-1)No test-article-related adverse findings in tumor-bearing mice; RNAseq showed immune infiltration/inflammation genes in injected tumors
Vyjuvek
beremagene geperpavec · COL7A1 (HSV-1, topical)Minimal to slight lymphoid hyperplasia in spleen and lymph nodes consistent with inflammatory response to vector
Waskyra
etuvetidigene autotemcel · WAS (LVV, ex vivo HSC)No dedicated immunotox studies; no anti-WASP antibodies in 27 treated patients
Zevaskyn
prademagene zamikeracel · COL7A1 (RV-modified keratinocyte sheets)Clinical only: transient anti-Col7 antibodies in 2/7 Phase 1/2a subjects; no systemic immune responses in Phase 3
Zolgensma
onasemnogene abeparvovec · SMN1Systemic inflammatory response in mice; capsid/transgene immunity proposed for atrial thrombosis; NHP antibodies to vector and transgene
Zynteglo
betibeglogene autotemcel · HBB T87Q (LVV, ex vivo HSC)No immunotoxicity studies; immunogenicity of beta-A-T87Q-globin not anticipated; patients immunosuppressed by busulfan
Kresladi
marnetegragene autotemcel · ITGB2 (LVV, ex vivo HSC)Not stated in public reviews
Lyfgenia
lovotibeglogene autotemcel · HBB T87Q (LVV, ex vivo HSC)Not stated in public reviews
Skysona
elivaldogene autotemcel · ABCD1 (LVV, ex vivo HSC)Not stated in public reviews
Strimvelis
autologous CD34+ cells transduced with ADA (no INN) · ADA (gamma-retroviral, ex vivo HSC)Not stated in public reviews