GSK has received two important regulatory updates for its medicines targeting chronic hepatitis B and locally advanced rectal cancer, giving the pharmaceutical company fresh momentum across its infectious disease and oncology portfolios.
Japan’s Ministry of Health, Labour and Welfare has approved Hibsago, also known as bepirovirsen, as a functional cure for certain adults with chronic hepatitis B virus infection. Separately, the US Food and Drug Administration has accepted GSK’s supplemental biologics license application for Jemperli, or dostarlimab, for priority review in a specific group of patients with locally advanced rectal cancer.
The developments come as pharmaceutical companies continue to pursue treatments that can deliver more durable outcomes for patients with serious diseases. While a hepatitis B vaccine remains an important tool for preventing infection, people who already have chronic infection require treatment strategies that can control the virus and reduce its long-term consequences. GSK’s bepirovirsen approval therefore represents a significant development in the company’s hepatitis portfolio.
Japan Approves GSK’s Bepirovirsen for Chronic Hepatitis B
Japan’s approval makes bepirovirsen the first globally approved medicine in its class to achieve a functional cure indication for chronic hepatitis B, according to GSK. The decision applies to adults who have completed at least six months of treatment with nucleos(t)ide analogue therapy and meet specified viral marker criteria.
The approval was supported by results from the Phase 3 B-Well clinical programme. According to GSK, the trials produced a functional cure rate of 19% when bepirovirsen was used in the relevant patient population, compared with approximately 1% after one year of standard care alone.
The distinction is important because chronic hepatitis B remains a long-term health challenge despite significant progress in prevention and disease management. Existing antiviral medicines can suppress the virus, but treatment often needs to continue for extended periods. A therapy capable of producing a functional cure could potentially change how eligible patients manage the disease.
Bepirovirsen is an antisense oligonucleotide designed to target hepatitis B viral RNA and reduce the production of viral proteins. Rather than simply suppressing viral replication, the treatment is being developed with the aim of enabling the immune system to regain control of the infection.
GSK said it is continuing regulatory submissions for bepirovirsen in other markets, including the US. Regulatory decisions in additional jurisdictions could determine how quickly the treatment reaches a wider population and whether its Japanese approval becomes the beginning of a broader commercial launch.
For GSK, the development also strengthens its position in infectious diseases at a time when the company is seeking growth from specialty medicines and vaccines while managing competition and patent-related pressures across its portfolio.
Jemperli Moves Into Priority FDA Review for Rectal Cancer
GSK also received a regulatory boost in the US after the FDA accepted its supplemental application for Jemperli for priority review.
The application covers patients with previously untreated stage 2 and stage 3 mismatch repair deficient or microsatellite instability-high locally advanced rectal cancer. These biological characteristics identify a subset of colorectal cancer patients whose tumours may respond particularly well to immune checkpoint treatment.
Jemperli is an immunotherapy that targets PD-1, a protein involved in regulating immune responses. GSK is seeking to expand its use based on results from the Phase 2 AZUR-1 study, which evaluated the medicine in patients with this specific form of rectal cancer.
The study achieved its primary objective, with patients demonstrating a sustained clinical complete response over a 12-month period. A clinical complete response means that no detectable evidence of the cancer was found through the assessments used in the study.
The potential significance extends beyond tumour response. If the treatment is approved for the proposed population, some patients could potentially avoid conventional approaches such as chemotherapy, radiation and surgery. That could represent a major shift in treatment planning for patients whose disease responds completely to immunotherapy.
The FDA has assigned February 2027 as the current action date for the application. GSK also said the application is eligible for expedited consideration under the National Priority Voucher programme, which could provide an opportunity for a decision earlier than the standard timeline.
The two regulatory developments highlight different aspects of GSK’s strategy. Bepirovirsen gives the company an opportunity to establish a new treatment category in chronic hepatitis B, while Jemperli is being positioned for further expansion within precision oncology.
From an industry perspective, both programmes also demonstrate the growing importance of identifying patient groups most likely to benefit from targeted treatment approaches. In hepatitis B, treatment eligibility is linked to prior therapy and viral markers. In rectal cancer, the Jemperli application is focused on tumour characteristics such as mismatch repair deficiency and microsatellite instability.
The immediate focus will now shift to regulatory decisions in additional markets for bepirovirsen and the FDA’s review of Jemperli. For GSK, successful outcomes could broaden the reach of both medicines and provide additional growth opportunities in two areas where treatment needs remain substantial.
