ImmunityBio’s leading oncology candidate, Anktiva (N-803), is now being considered by the US Food and Drug Administration (FDA) as a novel treatment for patients with Bacillus Calmette-Guérin (BCG) unresponsive non-muscle-invasive bladder cancer (NMIBC) carcinoma in situ (CIS) with or without Ta or T1 disease. A biologics license application (BLA) was submitted on 23 May based on data from the pivotal Phase II/III QUILT 3032 trial.

Anktiva is a next-generation cytokine, specifically an IL-15 fusion protein that forms a superagonist complex. The drug aims to enhance the anti-tumour immunity triggered by a variety of cancer therapeutics ‒ in this case, the BCG vaccine. QUILT 3032 is a single-group, open-label trial with complete response rate and disease-free rate as the primary endpoints for different cohorts. Patients with CIS who were previously unresponsive to BCG demonstrated a 71% response rate for the combination of Anktiva + BCG, with 96% of patients having a 24-month survival rate free of progression to muscle-invasive bladder cancer (MIBC). But although this data is favourable for Anktiva, the lack of an active comparator will make the results hard to contextualise and generate physician confidence.

BCG-unresponsive NMIBC is typically treated with cystectomy, intravesical chemotherapy or Merck’s Keytruda (pembrolizumab) for certain patients. Other drugs are in late-stage trials in combination with BCG for the same patient population, including AstraZeneca’s Imfinzi (durvalumab) and Sesen Bio’s Vicinium (oportuzumab monatox). The FDA previously rejected Sesen Bio’s BLA for the treatment of BCG-unresponsive patients, citing multiple issues, including a lack of randomised data comparing Vicinium with an investigator’s choice of intravesical chemotherapy. Sesen Bio, however, plans to address these issues and re-submit, keeping Vicinium active in the late-stage pipeline.

The bladder cancer market is relatively small compared to its incidence, as most patients are diagnosed in early stages and treatment is widely genericised. GlobalData valued the seven major markets (7MM: the US, France, Germany, Italy, Spain, the UK and Japan) at $1.1bn in 2022. With the current data from QUILT 3032, Anktiva is set to capture only a very small share of the BCG-unresponsive market. Based on the FDA’s treatment of Vicinium, the lack of an active compactor may well lead to a rejection of ImmunityBio’s BLA, requiring another Phase III study. Bladder cancer, while important, should not be a make-or-break indication for Anktiva, as ImmunityBio has a diversified portfolio of Phase II/III trials in other indications, including pancreatic cancer and non-small cell lung cancer, for Anktiva in combination with chemotherapy,