What's Happening?
GSK is anticipating an FDA decision on its antisense-based drug, bepirovirsen, for chronic hepatitis B (CHB) by October 26. The drug has received priority, fast-track, and breakthrough designations from the FDA, indicating its potential significance in treating
CHB, which affects over 250 million people globally. The FDA review is based on the B-WELL 1 and B-WELL 2 studies, which demonstrated that bepirovirsen achieved a statistically higher functional cure rate compared to placebo when added to standard care. Bepirovirsen works by targeting hepatitis B virus (HBV) messenger RNA and pregenomic RNA, disrupting the virus's replication and aiding the immune system in controlling the infection. While not a complete cure, achieving a functional cure significantly reduces the risk of liver complications and mortality associated with CHB.
Why It's Important?
The approval of bepirovirsen could represent a significant advancement in the treatment of chronic hepatitis B, a leading cause of liver cancer and responsible for approximately 1.1 million deaths annually worldwide. Current treatments often require lifelong therapy with low functional cure rates. Bepirovirsen's potential to improve cure rates could reduce the long-term health burden and mortality associated with CHB. GSK projects peak sales of around £2 billion annually, contributing to its goal of exceeding £40 million in annual revenues by 2031. The drug's approval could also stimulate further research and development in the field of hepatitis B treatment, potentially leading to more effective therapies.
What's Next?
GSK is conducting a long-term extension of the phase 2 B-Clear study, named B-Sure, which will follow patients for approximately three years, with results expected in 2029. Additionally, GSK's pipeline includes a gene-editing antisense oligonucleotide-based regimen for CHB, licensed from Johnson & Johnson, currently in phase 2 trials, and a PAPD5/PAPD7 inhibitor in phase 1. Analysts suggest the market for an HBV cure could be comparable to the hepatitis C virus market, which peaked at $10 billion annually. However, the hepatitis C market experienced a decline as the pool of eligible patients reduced, indicating potential challenges for sustained market growth.
