The FDA expanded its approval of Anktiva on Oct. 14 to adults with high-grade papillary-only bladder cancer that has not spread into the bladder muscle and has stopped responding to BCG. The agency said it is the first treatment approved specifically for that group.
What the FDA Approved
The FDA announcement covers Anktiva, whose generic name is nogapendekin alfa inbakicept-pmln, given together with Bacillus Calmette-Guérin, known as BCG. The FDA names Altor BioScience, LLC as the company, and ImmunityBio announced the approval the same day. The new use applies to adults with high-grade, papillary-only, non-muscle-invasive bladder cancer that no longer responds to BCG.
ImmunityBio said in its Oct. 14 announcement that the expanded label now covers both carcinoma in situ, with or without papillary tumors, and papillary-only tumors. Accounts of how common papillary disease is differ within that same release. One passage puts papillary disease at about 85% of the non-muscle-invasive bladder cancer population, and another passage says 85% to 90% of patients present with it.
The FDA first approved Anktiva with BCG in April 2024 for BCG-unresponsive disease with carcinoma in situ, according to ImmunityBio. The October action extends the label to papillary-only tumors.
The Evidence Behind the Expansion
The FDA did not base the expansion on a separate trial of papillary-only patients. The agency said it relied on the earlier carcinoma in situ approval together with evidence that the two forms share key features. Those features, the FDA said, include frequently occurring together, being difficult to tell apart under a microscope and carrying a high risk of recurrence or progression once BCG stops working.
The trial behind the earlier approval, NCT03022825, enrolled 77 adults. Some also had papillary tumors. According to the FDA, 62% had a complete response, meaning no high-grade cancer was found in follow-up. Among those who responded, 58% kept the response for at least 12 months and 40% for at least 24 months. ImmunityBio’s release puts the 95% confidence interval for the complete response rate at 51% to 73%.
Applied to the 77 patients, those percentages mean about 48 had a complete response, about 28 of them kept it for a year and about 19 for two years. These are calculations from the published percentages, rounded to whole patients.
The FDA’s page does not report results for the papillary-only group. ImmunityBio’s release identifies the trial as QUILT-3.032 and reports only Cohort A, the carcinoma in situ group. The trial included a papillary cohort, but the release does not include its results. Neither document gives a response rate for papillary-only patients.
That leaves the approval resting on a comparison between two forms of the disease, not on a measured papillary response rate. The agency’s rationale is that the forms resemble each other closely enough for the earlier evidence to carry over, and the FDA presented that reasoning as its basis.
How Treatment Works
Doctors give Anktiva directly into the bladder through a catheter once a week for six weeks, with further treatment based on the patient’s response. Treatment may continue for up to 37 months. The FDA said doctors should stop it if cancer persists after a second six-week course, returns or progresses or if side effects become unacceptable.
If the schedule runs to the full 37 months, a patient would spend about 160 weeks on treatment, a calculation from the FDA‘s figures that counts 37 months as roughly 160 weeks. The label sets the stopping rules above, and the agency’s announcement does not give an average treatment length.
Side Effects and a Warning about Surgery
The FDA listed the common side effects and abnormal lab results: painful or frequent urination, urgency, blood in the urine, urinary tract infections, muscle or joint pain, chills, fever and increased creatinine and potassium levels. The prescribing information carries a separate warning. Delaying surgery to remove all or part of the bladder can let the cancer spread to other parts of the body, and the agency said that can be fatal. The warning applies to patients whose cancer has outlasted BCG and who are weighing continued drug treatment against an operation.
What FDA and ImmunityBio Officials Said
R. Angelo de Claro, director of the FDA’s Oncology Center of Excellence, said in the announcement that the agency listens to patients, clinicians and researchers and that “we act when the science supports a new approach.”
Patrick Soon-Shiong, ImmunityBio’s founder and executive chairman, called the approval “an important first step” as the company develops what he described as immunotherapy 2.0. Richard Adcock, the company’s president and chief executive, said the approval establishes Anktiva as the first FDA-approved therapy for both carcinoma in situ and papillary-only disease.
Sam S. Chang, a professor of urology and chief surgical officer at Vanderbilt-Ingram Cancer Center, is quoted in the company’s release describing the approval as an important addition to the treatment landscape. The release does not state whether Chang has a financial relationship with ImmunityBio.
What Comes Next
The FDA said it is working to finalize its draft guidance titled “Bacillus Calmette-Guérin-Unresponsive Nonmuscle Invasive Bladder Cancer: Developing Drugs and Biological Products for Treatment.” The agency said the guidance is intended to cover the use of carcinoma in situ study evidence to support approval for high-grade papillary-only disease. Patients and doctors who want papillary-specific response data will have to wait for results that neither the agency nor the company has published in these announcements.
