ImmunityBio Gains FDA Expanded Approval for Anktiva in High-Grade Papillary BCG-Unresponsive NMIBC

ImmunityBio's Anktiva (nogapendekin alfa inbakicept-pmln) now carries a broader label following FDA approval on October 14, 2026 of an expanded indication covering adults with BCG-unresponsive non-muscle invasive bladder cancer (NMIBC) with high-grade papillary-only tumors, a population previously excluded from the approved use. For regulatory affairs leads and QA directors managing oncology biologics, the approval's mechanism is as consequential as the label change itself: FDA applied efficacy extrapolation across two histologically distinct tumor subtypes rather than requiring a separate pivotal trial.

The original indication, granted on the strength of Cohort A data from the single-arm, multicenter QUILT-3.032 trial (NCT03022825), covered BCG-unresponsive NMIBC with carcinoma in situ (CIS) with or without papillary tumors. That 77-patient cohort achieved a complete response rate of 62% (95% CI: 51, 73), with 58% of responders maintaining response at 12 months and 40% at 24 months. FDA's extrapolation to high-grade papillary-only disease rested on the overlapping clinical and non-clinical profiles of CIS and high-grade papillary urothelial carcinoma, shared aggressiveness, frequent coexistence, pathological ambiguity, and equivalent recurrence and progression risk in the BCG-unresponsive setting.

The regulatory precedent here warrants close attention from indication expansion teams. FDA explicitly acknowledged that the two histologic subtypes differ in architectural growth features, yet concluded the prior efficacy demonstration was sufficient to support extrapolation. The agency is concurrently working to finalize its guidance document, Bacillus Calmette-Guérin-Unresponsive Nonmuscle Invasive Bladder Cancer: Developing Drugs and Biological Products for Treatment, which is expected to codify this extrapolation framework for future applicants.

On the manufacturing and pharmacovigilance side, the approved dosing regimen runs to a maximum of 37 months: 400 mcg intravesical instillation with BCG weekly for six weeks as induction, with defined maintenance cycles at months 4, 7, 10, 13, 19, and optionally through month 37 for eligible patients. A second induction course is permissible at month 3 for residual CIS or high-grade Ta disease. The prescribing information carries a warning that delayed cystectomy may result in metastatic progression. The most common adverse reactions at or above the 15% threshold include increased creatinine, dysuria, hematuria, urinary frequency, urinary tract infection, and pyrexia. Updated full prescribing information will be posted to Drugs@FDA.

The finalization timeline for FDA's BCG-unresponsive NMIBC guidance document will serve as the clearest signal of how broadly the agency intends to apply this extrapolation standard across future NMIBC development programs.

Source: FDA Drugs@FDA / What's New: Drugs RSS Feed, October 14, 2026.