Adstiladrin
nadofaragene firadenovec · IFN-alpha2b (adenovirus, intravesical)No carcinogenicity studies with vector or novel excipient; weight-of-evidence assessment for a non-advanced cancer indication
Lenmeldy: what flexibility did regulators accept, and why?
atidarsagene autotemcel · ARSA (LVV, ex vivo HSC)
Flexibility accepted
DARTAcceptedBeyond the letter
No reproductive and developmental toxicity studies
Why: Ex vivo transduction with replication-incompetent vector; no bystander transduction or vector mobilisation observed in animals · Low-risk modality · Weight of evidence
“As the transduction of the cells occurs ex vivo, the risk for transduction of the gametes and consequently the risk from germline transduction is limited and rather theoretical.”
“The absence of dedicated studies addressing the reproductive and developmental toxicity can thus be agreed upon.”
CarcinogenicityAcceptedBeyond the letter
No standard carcinogenicity studies; tumorigenicity assessed in mouse transplantation studies and integration analyses
Why: Product characteristics and safety profile · Weight of evidence
“Carcinogenicity and developmental and reproductive toxicity studies were not conducted with OTL-200. These studies are not warranted based on the product characteristics and safety profile.”
GenotoxicityVerdict not stated
Insertional mutagenesis (immortalization assay, tumor-prone mice) tested with a GFP-expressing vector sharing the ARSA vector backbone
Why: GFP vector shares the same lentiviral backbone · Class precedent
“No evidence of insertional mutagenesis of the LVV backbone in an in vitro immortalization (IVIM) assay and no increase in tumorigenesis in vivo in a tumor-prone mouse model were demonstrated using a LVV expressing GFP, which shares the same LVV backbone as that of ARSA LVV.”
OtherVerdict not stated
Toxicity studies used murine HSPCs with total-body irradiation conditioning instead of clinical busulfan
Why: Total-body irradiation better tolerated than busulfan in mice
“Because TBI was better tolerated, the applicant used this regimen for pre-conditioning in the long-term toxicity studies. Clinically, busulfan instead of irradiation is used as a pre-conditioning regimen.”
Same question, other gene therapies
Beqvez
fidanacogene elaparvovec · Factor IXDefinitive 3-month monkey GLP toxicity study used a closely related predecessor vector, not the clinical product
Casgevy
exagamglogene autotemcel · BCL11A enhancer (CRISPR-Cas9, ex vivo HSC)No in vivo proof-of-concept study; no disease model for TDT or SCD, so engraftment and editing persistence studied in NSG xenotransplant mice
Elevidys
delandistrogene moxeparvovec · Micro-dystrophinNo developmental and reproductive toxicology studies
Fayuvi
rebisufligene etisparvovec · SGSH (AAV9)No genotoxicity or carcinogenicity/tumorigenicity studies; weight-of-evidence risk assessment instead
Genglycos
pariglasgene brecaparvovec · G6PC (AAV8)No carcinogenicity/tumorigenicity studies; justified by low integration risk of episomal AAV8 vector and literature
Glybera
alipogene tiparvovec · LPL (AAV1)Toxicity evaluated in a single species (wild-type mice) only
Hemgenix
etranacogene dezaparvovec · Factor IXSeveral toxicology studies used predecessor vector AMT-060 (wild-type hFIX) instead of the final product
Imlygic
talimogene laherparepvec · GM-CSF (oncolytic HSV-1)No genotoxicity studies; non-integrating HSV-1 episome
Itvisma
onasemnogene abeparvovec (intrathecal) · SMN1 (AAV9, intrathecal)No NOAEL in the pivotal intrathecal NHP study; DRG, spinal cord, nerve and brain findings at the clinical-equivalent dose
Kebilidi
eladocagene exuparvovec · AADCNo in vivo pharmacology studies with the product; in vitro human cell data plus published literature only
Kresladi
marnetegragene autotemcel · ITGB2 (LVV, ex vivo HSC)Clinical product not tested; surrogate murine Lin- HSPCs transduced with the clinical vector used for definitive toxicology and biodistribution
Luxturna
voretigene neparvovec · RPE65No reproductive toxicity studies; gonadal biodistribution in dogs and primates used instead
Lyfgenia
lovotibeglogene autotemcel · HBB T87Q (LVV, ex vivo HSC)No traditional carcinogenicity studies; insertional mutagenesis assessed by in vitro immortalization assay and integration site analysis
Otarmeni
lunsotogene parvec · OTOF (AAV, intracochlear)No genotoxicity or carcinogenicity/tumorigenicity studies; tumorigenicity risk to be assessed in a postmarketing study
Papzimeos
zopapogene imadenovec · HPV6/11 antigens (gorilla adenovirus)Definitive repeat-dose toxicology study non-GLP, in wild-type mice only; murine antigen processing likely differs from human
Roctavian
valoctocogene roxaparvovec · Factor VIIINo carcinogenicity or tumorigenicity studies (nor safety pharmacology or DART studies)
Skysona
elivaldogene autotemcel · ABCD1 (LVV, ex vivo HSC)Safety tested only in single-dose studies in immunodeficient myeloablated mice given healthy-donor transduced cells
Strimvelis
autologous CD34+ cells transduced with ADA (no INN) · ADA (gamma-retroviral, ex vivo HSC)No tumorigenicity study: long-term engraftment of transduced cells in mice not achievable; risk assessed from clinical data and vector literature
Tudriqev
vusolimogene oderparepvec · GALV-GP + GM-CSF (oncolytic HSV-1)Rat toxicology, biodistribution and DART studies used the murine surrogate mRP1 (murine GM-CSF); clinical product tested only in tumor-bearing mice
Vyjuvek
beremagene geperpavec · COL7A1 (HSV-1, topical)Toxicity tested in a single species (mouse), chosen only on historical use
Waskyra
etuvetidigene autotemcel · WAS (LVV, ex vivo HSC)Pharmacology and toxicology done with murine surrogate HSPCs transduced with the WAS vector in mice, not the human product
Zevaskyn
prademagene zamikeracel · COL7A1 (RV-modified keratinocyte sheets)No carcinogenicity or tumorigenicity studies; insertional oncogenesis risk deferred to a long-term postmarketing safety study
Zolgensma
onasemnogene abeparvovec · SMN1Pivotal toxicity in neonatal mice only; no adequate safety study in a species closer to human (NHP study non-GLP, low-dose pilot)
Zynteglo
betibeglogene autotemcel · HBB T87Q (LVV, ex vivo HSC)No carcinogenicity studies; low risk of oncogenic transformation concluded from the available vector data