FDA Approves Bladder Cancer Immunotherapy

The FDA has approved the biologics license application (BLA) for ImmunityBio’s Anktiva (N-803, or nogapendekin alfa inbakicept-pmln) in combination with Bacillus Calmette-Guérin (BCG) vaccine. Anktiva, an antibody cytokine fusion protein, is approved to treat BCG-unresponsive non-muscle invasive bladder cancer.

The American Cancer Society estimates there will be about 83,190 new cases of bladder cancer in 2024, with 16,840 deaths. Bladder cancer incidence rates slowed in the late 2000s, but picked up again from 2015 to 2019. Deaths from bladder cancer have declined from 2015 to 2021. The BCG vaccine is the current standard of care in this cancer.

The cytokine interleukin-15 (IL-15) plays a crucial role in the immune system by affecting the development, maintenance, and function of the natural killer and T cells. Anktiva, an IL-15 superagonist, has a mechanism of action that leads to the proliferation of natural killer and T cells. This provides a boost to the immunological response generated by BCG.

Anktiva will be available mid-May 2024. No information was provided about the pricing of the Anktiva.

Patrick Soon-Shiong, M.D.

“The combination of the proliferation of key cancer-killing immune cells, together with the activation of T cells with memory, results in durable complete responses,” Patrick Soon-Shiong, M.D., executive chairman and global chief scientific and medical officer at ImmunityBio, explained in a news release.

The approval is based on the safety and efficacy outcome of complete responses (CR) and duration of complete response (DOR). The 77 evaluable patients in a single-arm QUILT 3.032 study received Anktiva with BCG maintenance therapy for up to 37 months. The complete response rate was 62% and the duration of complete response as of the November 2023 cut-off was more than 47 months and is ongoing. Fifty-eight percent (58%) of patients with complete response had a duration of response ≥ 12 months and 40% had a duration of response at ≥ 24 months.

Most treatment-emergent adverse events for patients were grade 1 to 2 (86%), including hematuria (blood in the urine) and urinary tract infection. Other adverse reactions include adverse reactions, including laboratory test abnormalities were increased creatinine, dysuria, hematuria, urinary frequency, micturition urgency, urinary tract infection, increased potassium, musculoskeletal pain, chills, and pyrexia.

Three grade 3 immune-related treatment-emergent adverse events occurred in the trial and included immune-related events, hematuria, and stroke. There was a single death from cardiac arrest that was considered a treatment-related event.

Karim Chamie, M.D.

“The long duration of complete response ranging over 47 months is a game changer for NMIBC patients,” said Karim Chamie, M.D., associate professor of urology at UCLA and principal investigator for the QUILT 3.032 study.

Results from the study were published in November 2022 on NEJM Evidence. Additional updates on the ongoing analysis of QUILT-3.032 will be presented by Soon-Shiong at the upcoming American Urological Association’s annual conference on May 3, 2024.

Additionally, in February 2024, the company reported data from Patient-Reported Outcomes (PROs) of patients in the phase 2/3 QUILT 3.032 study. Patients reported that both physical function and global health remained stable over the two-year course of the study. Overall, patients who achieved a complete response with therapy reported better physical function by month six of the study than those who did not achieve a complete response.

Related: FDA Sets New Review Date for Bladder Cancer Immunotherapy

In May 2023, the FDA had issued a complete response letter for ImmunityBio’s original BLA. Company officials said in a news release in October 2023 when they resubmitted the BLA they had provided regulators with an update on the duration of complete response in BCG-unresponsive patients from the QUILT-3.032 study that demonstrated a prolonged duration of remission. In the responding BCG-unresponsive patients updated efficacy data demonstrated a probability of avoiding a cystectomy at more than 24 months of more than 90%.