Clinical only: transient anti-Col7 antibodies in 2/7 Phase 1/2a subjects; no systemic immune responses in Phase 3
“In the Phase 1/2a study, circulating anti-Col7 antibodies were detected in two out of seven subjects, which resolved without intervention by 1 year after treatment.”
✓ VerifiedFDA summary basis for approval, p. 13Source ↗
Biodistribution & persistence
COL7A1 transgene DNA confined to explanted product at 4 and 8 weeks; below detection in all other tissues
“COL7A1 transgene DNA was detected in explanted nonclinical products at both sacrifice time points.”
✓ VerifiedFDA summary basis for approval, p. 12Source ↗
“Integration site analysis in RDEB keratinocytes transduced with LZRSE-Col7A1 showed a low level of integration distributed throughout the host genome with no predilection to specific integration sites, including in genes associated with malignant transformation in humans.”
Not reported in the public reviews. Reviewers summarise selectively, so this usually means it wasn't discussed publicly, not that it wasn't studied.
Anti-drug antibodies: patients
Circulating anti-C7 antibodies in 2 of 7 patients (resolved by 1 year); tissue-bound in 4
“Out of 7 patients, circulating anti-C7 antibodies were detected in 2 patients which resolved at 1 year follow-up. Tissue-bound anti-C7 antibodies were detected in 4 patients which resolved in 3 patients at 1 year follow-up.”