ImmunityBio has received authorization from the FDA to provide recombinant BCG (rBCG) to urologists, offering a potential solution to the ongoing TICE® BCG shortage that has affected bladder cancer treatment across the United States.
The newly authorized rBCG represents a significant advancement in BCG therapy, featuring two genetic modifications specifically designed to enhance its immunogenicity and safety profile compared to conventional BCG formulations. Clinical evidence supporting this development comes from completed Phase 1/2 human studies conducted in Europe, focusing on non-muscle invasive bladder cancer (NMIBC) patients.
Clinical Evidence and Safety Profile
The European clinical trials have yielded promising results, demonstrating that rBCG is well-tolerated when administered intravesically. Notably, the safety profile was comparable to placebo, with reduced adverse events compared to earlier BCG strains and formulations.
Supporting data extends beyond bladder cancer applications. Four additional clinical trials have evaluated rBCG's efficacy as a tuberculosis vaccine, including studies in:
- Healthy adult volunteers
- Healthy newborn infants
- HIV-unexposed and HIV-exposed, BCG-naïve newborn infants
- Assessment of TB recurrence and respiratory disease susceptibility during the SARS-CoV-2 pandemic
Manufacturing and Supply Context
BCG's manufacturing complexity stems from its nature as a biologic drug utilizing benign bacteria, making production more challenging than conventional pharmaceuticals. Currently, while the Serum Institute of India stands as the world's largest BCG vaccine manufacturer, Merck & Co. remains the sole U.S. manufacturer of TICE® BCG.
Innovation in Treatment Approach
ImmunityBio's intellectual property portfolio includes multiple patents covering both the composition and methods of using BCG in combination with ANKTIVA for bladder cancer treatment. This combination approach represents a novel strategy in addressing bladder cancer, with ANKTIVA recently receiving FDA approval in 2024 for BCG-unresponsive non-muscle invasive bladder cancer CIS.
Therapeutic Mechanism
The rBCG development builds upon BCG's established role as one of the world's most widely used vaccines. The genetic modifications implemented in rBCG aim to enhance its therapeutic potential while maintaining the proven benefits of traditional BCG therapy. This advancement comes at a crucial time when supply constraints have limited treatment options for bladder cancer patients.
The authorization enables ImmunityBio to establish an alternative source of BCG for U.S. patients, potentially alleviating the current shortage while offering a modified version that may provide improved therapeutic outcomes through enhanced immunogenicity and safety profiles.
