On December 16, 2022, the U.S. Food and Drug Administration (FDA) approved Adstiladrin® (nadofaragene firadenovec-vncg) for the treatment of high-risk non-muscle-invasive bladder cancer (NMIBC) in adult patients whose cancer has not responded to treatment with Bacillus Calmette-Guérin (BCG) therapy. Bladder cancer is a common form of cancer in which malignant cells grow in, and potentially destroy, the tissues of the bladder. Non-muscle-invasive bladder cancer (NMIBC) makes up nearly 80% of newly diagnosed bladder cancers. NMIBC tumors grow through the lining of the bladder but do not reach the muscle layer surrounding the bladder. In its earlier stages, this form of bladder cancer is often removed and then treated with BCG, a therapy administered into the bladder that prompts the body’s immune system to attack cancer cells. When unresponsive to BCG, patients are at a much higher risk of progression of the disease and the spread of cancer cells to other areas of the body. Limited treatment options exist for these patients. Adstiladrin® was granted Priority Review, Breakthrough Therapy and Fast Track designations by the FDA to address this critical need.
Adstiladrin® is a gene therapy intended for use in BCG-unresponsive patients. It uses adenoviruses to deliver instructions to the bladder cells to produce a protein with antitumor activity. The adenoviruses used for gene therapy do not replicate in human cells and do not cause infectious diseases. Adstiladrin® is administered directly into the bladder once every three months via a urinary catheter. The safety and effectiveness of Adstiladrin® were tested in a study of 98 patients, and the therapy was administered for up to 12 months. A complete response to the drug was defined as the disappearance of all signs of cancer seen in biopsied tissue, bladder scope and urine. In the study, 51% of patients receiving Adstiladrin® therapy achieved a complete response for an average of 9.7 months and, of those 46% (23% of the initial group) continued to show no signs of cancer for at least one year. The most common adverse reactions reported were bladder discharge and spasms, urgent and painful urination, presence of blood in urine, chills, fever and fatigue.