Researchers at Sechenov University said they had created a drug for chronic hepatitis B based on CRISPR/Cas9 technology. According to the authors, the system is designed to precisely target affected sites and remove viral DNA from liver cells. A number of Russian media outlets described it as the first drug of its kind with no global equivalent, but experts say that claim is overstated.
Sources interviewed by Novaya Gazeta Europe explain that CRISPR/Cas originally functions as a natural bacterial defense system. Cas proteins identify viral DNA using stored fragments and cut it apart, which is why the technology is often called “genetic scissors.” In 2012, Emmanuelle Charpentier and Jennifer Doudna showed that this mechanism could be used for genome editing, and within a year it became clear that it also worked in mammalian cells.
The method, however, carries risks. Molecular biologist Victoria Doronina says off-target effects are possible, meaning the cut may occur not at the intended site but in a similar DNA sequence. In her words, the outcome of such intervention can be unpredictable.
CRISPR-based therapies have been under study in multiple countries for years. In 2022, Britain recorded its first case of therapeutic genome editing in a 13-year-old patient with acute T-cell leukemia. In 2023, the United States and then the United Kingdom approved the first cell gene therapies for sickle cell disease. Treatments for HIV and hepatitis B are also in development, including PBGENE-HBV by Precision BioSciences, which received FDA clearance for clinical trials.
“There is no evidence that the Russian drug has passed even the first phase of clinical trials,” Victoria Doronina says.
In her assessment, without such trials it is impossible to judge the treatment’s effectiveness beyond the developers’ own experiments. For that reason, claims of global primacy or a finished medical breakthrough remain premature.