Balversa™ (erdafitinib) is one of the first fibroblast growth factor receptor (FGFR) kinase inhibitors to be approved for the treatment of locally advanced or metastatic urothelial carcinoma.
The drug was discovered and developed by Astex Pharmaceuticals and Janssen Pharmaceutical under a collaboration agreement signed in June 2008.
The drug received breakthrough therapy designation from the US Food and Drug Administration (FDA) in March 2018. Janssen then submitted a new drug application (NDA) in September 2018 and received a priority review designation. The FDA provided accelerated approval to the drug in April 2019.
The FDA-approved companion diagnostic device QIAGEN therascreen® will be used to determine a patient’s eligibility for Balversa. Developed by QIAGEN Manchester, the polymerase chain reaction (PCR) kit is one of the first FDA-approved PCR-based companion diagnostics to detect FGFR mutations.
Urothelial Carcinoma causes and symptoms
Also known as transitional cell carcinoma, urothelial carcinoma begins to develop in the innermost lining of the bladder. It is one of the most common forms of bladder cancer and the sixth most common type of cancer in the US.
The disease occurs in more than 90% of bladder cancer cases, and one out of five advanced urothelial carcinoma patients have a mutation in the FGFR gene, which is responsible for increased tumour cell growth and survival.
An estimated 3,000 urothelial carcinoma patients are tested FGFR positive in the US annually. The five-year survival rate of stage IV metastatic bladder cancer patients is less than 5%.
Balversa’s mechanism of action
Balversa is a once-daily oral FGFR kinase inhibitor indicated to treat urothelial carcinoma patients with FGFR3 or FGFR2 genetic mutations and whose cancer has progressed after platinum-containing chemotherapy.
The drug binds to and inhibits the enzymatic activity of FGFR. It causes inhibition of FGFR phosphorylation and signalling. The anti-tumour activity of Balversa leads to the death of cancerous cells.
Balversa is available as a round, biconvex, film-coated tablet in 3mg, 4mg or 5mg strengths. The 3mg tablet is yellow in colour, while the 4mg tablet is orange and the 5mg tablet is brown.
Clinical trials on Balversa
The FDA’s approval of the drug was based on the positive results of a pivotal multi-centre, open-label, Phase II clinical study named BLC2001. The study enrolled 87 patients with metastatic urothelial carcinoma and had a primary endpoint of tumour response rate.
Patients were initially administered with 8mg of Balversa once daily, which was increased up to 9mg. The clinical trial showed a 32.2% objective response rate with 2.3% of patients achieving a complete response and 29.9% achieving a partial response. The median duration of response in patients was 5.4 months.
The most common adverse events reported during the clinical trial were an increase in phosphate and calcium; a decrease in sodium, magnesium, phosphate and albumin; stomatitis; fatigue; diarrhoea; onycholysis; and dry skin, as well as a decrease in haemoglobin count; impaired sense of taste; abdominal pain; nausea and musculoskeletal pain.
Marketing commentary on Janssen and Astex
Based in Belgium, Janssen is a pharmaceutical company of Johnson & Johnson (J&J). Janssen is focused on various areas of medicine, including immunology, oncology, infectious diseases, the cardiovascular system and metabolism.
Based in the UK, Astex is a biotechnology company that discovers and develops therapeutics. It focuses on oncology and central nervous system. The company is working in partnership with Novartis for Kisqali® (ribociclib) for the treatment of breast cancer, with AstraZeneca for capivasertib, which is being investigated as treatment for various forms of cancer, and with GlaxoSmithKline for multiple targets and therapeutic areas.