What is the story about?
Researchers announced on Thursday that an innovative drug for hepatitis B has enabled some patients to cease treatment while remaining free of detectable
virus, a phenomenon referred to as a 'functional cure.' In two international studies, approximately 20% of participants receiving the experimental drug experienced a significant reduction in virus levels, allowing their immune systems to manage the infection effectively.
Significance of the Findings
Dr. Seng Gee Lim from the National University Health System of Singapore, who co-led the GSK-funded studies, expressed optimism about the results, stating, 'We have not had a treatment which has come to this level of cure.' The findings were also published in the New England Journal of Medicine.Chronic hepatitis B poses severe health risks, including liver cancer and liver failure, causing approximately 1.1 million deaths globally each year. Efforts to improve existing lifelong therapies, which can be challenging to adhere to or access, have been ongoing for decades.
Details of the Experimental Drug
The drug, named bepirovirsen and developed by GSK in collaboration with Ionis Pharmaceuticals, is currently under fast-track review by the U.S. Food and Drug Administration, with a decision anticipated in October. Regulatory authorities in Japan, China, and Europe are also evaluating the drug.Hepatitis B is transmitted through contact with infected bodily fluids, including during childbirth. While an effective vaccine exists, the infection can lead to acute illness lasting several months for many. However, about 1.7 million people in the U.S. and over 250 million worldwide develop a chronic form of the disease, which gradually harms the liver.
Trial Outcomes and Implications
In the trials, 1,838 patients received either a bepi injection or a placebo weekly for six months, alongside their standard medications. If their virus remained undetectable for six months after stopping the injections, they could also discontinue their regular medications. Researchers found that about 20% of those receiving bepirovirsen maintained undetectable virus levels for an additional six months, achieving a 'functional cure,' a result not seen in any placebo recipients.Lim noted that participants with lower initial levels of the S protein had a higher likelihood of achieving a functional cure. He is conducting further research to understand why the response varies among individuals.
Safety and Future Research
Regarding the durability of the functional cure, GSK has monitored a small cohort from earlier studies, reporting that most patients remained stable for up to three years. Mild side effects included redness or pain at the injection site and a temporary increase in liver enzymes.Dr. Anna Lok, a hepatitis specialist at the University of Michigan, acknowledged the significance of the findings but emphasized the need for further studies, particularly as the trials did not include patients with advanced liver disease or other complicating factors.
