The Saudi Arabian Food and Drug Authority has cleared Anktiva, an IL-15–based immunotherapy created by billionaire physician-scientist Patrick Soon-Shiong and his biotech firm ImmunityBio, for the treatment of bladder cancer and lung cancer. This marks the first time the therapy has received national regulatory approval outside the United States.The move signals an important global step for Anktiva, which currently holds a limited approval from the U.S. Food and Drug Administration. In the U.S., the drug is authorised only for patients with BCG-unresponsive, non–muscle-invasive bladder cancer (NMIBC) that includes carcinoma in situ. American regulators have so far resisted expanding its use to other bladder cancer subtypes. Saudi regulators, however, have adopted a broader stance, approving Anktiva for two cancer types under their domestic regulatory system.What Is Anktiva?Anktiva is an interleukin-15 receptor agonist designed to stimulate the body’s own immune defences. It works by activating and expanding natural killer (NK) cells and memory CD8⁺ T cells, which play a key role in immune surveillance. Unlike chemotherapy or gene-based treatments, Anktiva does not attack tumour cells directly. Instead, it boosts existing immune pathways to help the body recognise and destroy cancer cells.ImmunityBio describes Anktiva as “the first FDA-approved immunotherapy that activates what’s called a natural killer cell to target and kill non-muscle-invasive bladder cancer cells.” In clinical practice, the drug is used alongside BCG (Bacillus Calmette-Guérin) in patients whose NMIBC has not responded to BCG alone. It is administered directly into the bladder through a catheter, followed by a structured maintenance scheduleClinical Evidence Supporting FDA Approval in NMIBCThe FDA’s approval, issued on April 22, 2024, was based on results from a single-arm clinical study involving 77 patients with BCG-unresponsive stage 0 NMIBC. Participants received intravesical Anktiva combined with BCG, with maintenance therapy continuing for as long as 37 months.The main efficacy results were as follows:Complete response rate: 62%Durability:58% of patients who responded remained disease-free for at least 12 months40% stayed disease-free for 24 months or longerFor patients facing the prospect of radical cystectomy as the only curative option, these results were considered clinically significant. Still, the absence of a randomised control group has remained a point of contention among regulators and experts.Regulatory Tension in the United StatesAlthough the FDA approved Anktiva for NMIBC cases involving carcinoma in situ, it declined to extend the indication to patients with papillary-only disease. ImmunityBio pushed back against the decision, arguing that the same clinical data had already been deemed sufficient to support approval in a closely related patient group.Rachel Sherman, MD, former principal deputy commissioner of the FDA, publicly criticised the agency’s stance, saying: “it is incomprehensible to me that the FDA refuses to file a supplemental BLA, stating the study is not sufficient to support a regulatory review, when it has already approved a product based on that very same study in essentially the same indication and population.”The FDA has also expressed concerns about how the drug has been marketed. It issued a warning letter to ImmunityBio over promotional materials that cited survival benefits and cystectomy-avoidance rates not supported by robust evidence.Saudi regulators, by contrast, have taken a more permissive view, approving Anktiva for both bladder and lung cancer and highlighting a willingness to act in areas of high unmet medical need.With this decision, Saudi Arabia becomes the first country to approve Anktiva beyond NMIBC, potentially placing itself at the forefront of evaluating the therapy’s wider role across multiple cancer types.