Unlocking New Nonsurgical Treatment Options for Papillary NMIBC
In a major regulatory milestone for urological oncology, the U.S. FDA granted label expansion for ImmunityBio’s first-in-class interleukin-15 (IL-15) receptor agonist, Anktiva (nogapendekin alfa inbakicept-pmln). Used in combination with intravesical BCG, the treatment is now approved for patients with high-grade, papillary-only non-muscle-invasive bladder cancer (NMIBC) who have failed standard BCG therapy.
The decision builds upon Anktiva’s initial April 2024 FDA approval for BCG-unresponsive NMIBC with carcinoma in situ (CIS), with or without papillary tumors. By extending approval to papillary-only disease—which accounts for nearly 85 per cent of all NMIBC cases—the regulatory decision significantly expands nonsurgical therapeutic options for patients facing radical cystectomy (bladder removal).
Overview: Key Regulatory and Clinical Parameters of Anktiva's Label Expansion
| Clinical / Regulatory Parameter | Official Details & Trial Specifications |
| Drug Name & Class | Anktiva (nogapendekin alfa inbakicept-pmln) • IL-15 Receptor Agonist |
| Sponsoring Company | ImmunityBio, Inc. |
| Expanded Indication | BCG-unresponsive high-grade papillary-only NMIBC |
| Supporting Trial | QUILT-3.032 Phase 2/3 Trial (NCT03022825) |
| Cohort B Clinical Milestone | 58.2% 12-Month Disease-Free Survival (DFS) Rate |
| Mechanism of Action | Activates Natural Killer (NK) cells & CD8+ Killer T cells |
| Administration Route | Intravesical instillation directly into the bladder alongside BCG |
Mechanism of Action and QUILT-3.032 Trial Evidence
Anktiva functions as an immune cell enhancer by complexing a mutated IL-15 protein with an IL-15 receptor-alpha domain. When instilled directly into the bladder, it stimulates natural killer (NK) cells and CD8+ killer T cells while building memory T-cell populations, driving sustained antitumor responses without systemic immunosuppression.
Anktiva Immune Activation Pipeline: ----------------------------------- Intravesical Instillation with BCG ──> IL-15 Receptor Complexing ──> NK Cell & CD8+ T Cell Proliferation ──> Target Papillary Tumor DestructionThe expansion was supported by data from the open-label Phase 2/3 QUILT-3.032 trial. In Cohort B—which specifically evaluated patients presenting with BCG-unresponsive high-grade papillary-only disease—Anktiva plus BCG demonstrated a 12-month disease-free survival (DFS) rate of 58.2 per cent.
"This approval marks an important expansion of Anktiva plus BCG for patients with BCG-unresponsive NMIBC and advances our goal of harnessing the patient's own immune system to achieve durable, tumor-free outcomes," stated Dr. Patrick Soon-Shiong, Founder and Executive Chairman of ImmunityBio.
Safety Profile and Market Outlook
The safety profile observed in papillary-only patients aligns with previous CIS trial findings. Most treatment-related adverse events were localized to the urinary tract—such as dysuria, pollakiuria, hematuria, and urinary urgency—and were primarily Grade 1 or 2 in severity.
With the expanded label in place, ImmunityBio plans to scale commercial distribution to urology centers across the United States immediately, providing a key alternative for patients who previously had few options outside of radical bladder resection.

