GSK’s Bepirovirsen Accepted for Review

GSK plc (LSE/NYSE: GSK) shares are in focus as the European Medicines Agency (EMA) has accepted for review its marketing authorisation application (MAA) for bepirovirsen, an investigational antisense oligonucleotide (ASO) targeting chronic hepatitis B (CHB).

This acceptance marks a significant step for what could be a first-in-class treatment in a market with substantial unmet needs.

The submission is supported by data from the pivotal Phase III B-Well 1 and B-Well 2 trials. These trials showcased statistically significant and clinically meaningful functional cure rates. This is particularly important considering the limitations of current standard-of-care treatments, which often require lifelong therapy and yield low functional cure rates of approximately 1%.

Functional cure, defined as the sustained absence of hepatitis B virus DNA and hepatitis B surface antigen (HBsAg) in the blood for at least 24 weeks post-treatment, is a critical goal in CHB management. It signifies the immune system’s ability to control the virus without ongoing medication. The potential for bepirovirsen to achieve this could dramatically alter treatment paradigms.

The B-Well trials demonstrated that bepirovirsen, when added to the standard of care, resulted in significantly higher functional cure rates compared to the standard of care alone. Notably, the effect was even more pronounced in patients with lower baseline surface antigen levels(<=1000 IU/ml). The safety profile observed in these trials was consistent with previous studies, adding further confidence to the drug’s potential.

Driver Breakdown:

• Functional Cure Rates: Bepirovirsen demonstrated statistically significant and clinically meaningful functional cure rates in Phase III trials.
• Unmet Need: Current treatments for chronic hepatitis B have low functional cure rates, highlighting the need for new therapeutic options.
• Market Potential: An estimated 3.2 million people in Europe live with chronic hepatitis B, representing a substantial market opportunity.

Analyst Summary: Bull and Bear Cases