Adstiladrin
nadofaragene firadenovec · IFN-alpha2b (adenovirus, intravesical)Neutralizing anti-adenovirus and anti-IFNa2b antibodies in most high-dose monkeys, persisting through observation period
Elevidys: which risks did reviewers probe?
delandistrogene moxeparvovec · Micro-dystrophin
Immune & cytokine safety
Anti-AAV antibodies in mice; NHP: capsid/transgene T-cell responses, liver enzymes, anaphylaxis on redosing with rituximab/sirolimus
“increased antibody titers against AAVrh74 vector capsid from Weeks 5 to 12, increased cellular immune response against AAVrh74 vector capsid and micro-dystrophin at Week 2 compared to baseline”
Biodistribution & persistence
Systemic; highest in liver, then adrenal, aorta, heart, muscle; low in testes; shedding in urine/feces/plasma cleared by Day 44
“Systemic ELEVIDYS distribution was observed, with the highest vector levels in the liver, followed by the adrenal gland, aorta, heart, muscle, and esophagus.”
Modality-specific risk
AAV capsid immunity and liver/muscle inflammation; germline transmission; AAV integration (deemed low)
“The potential for the histopathology findings in the liver, heart, and skeletal muscles to be related to test article could not be determined due to the lack of a control group.”
Anti-drug antibodies: animals
Anti-AAV antibodies rose in WT and mdx mice by Weeks 3-4 and plateaued by Weeks 20-25
“Increased anti-AAV antibodies were observed in C57BL/6J and mdx mice administered SRP-9001 at ≥1.3 x 1014 vg/kg compared to baseline when assessed at Weeks 3 or 4, and plateaued by Weeks 20 or 25.”
Anti-drug antibodies: patients
Elevated anti-AAVrh74 total binding antibodies in all 156 patients after infusion
“Across clinical studies evaluating a total of 156 patients, elevated anti-AAVrh74 total binding antibodies titers were observed in all patients following a one-time ELEVIDYS infusion.”
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)
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
Imlygic
talimogene laherparepvec · GM-CSF (oncolytic HSV-1)Lethal disseminated HSV infection in immunodeficient mice (up to 20% nude, 100% SCID); immunocompetent mice tolerated doses
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