Is Regulus' injectable the next HCV blockbuster in the making?
- Regulus Therapeutics is developing a microRNA treatment for hepatitis C (HCV) that is targeted at a genetic target in the liver.
- In very early-stage trials, 14 HCV-infected patients were injected with the treatment (RG-101) and their viral loads dropped an average of 4.1 log in 29 days (compared with an average of 4 log drops with oral treatments, such as Gilead's blockbuster Sovaldi).
- Although the early-stage results were impressive, there is much more research to be done. For instance, it's important to see if the results are sustainable over time.
The advent of the oral hepatitis pills from Gilead (Sovaldi) and from Merck was truly a game-changer for the treatment of HCV—in large part because they offer an oral, interferon-free regimen with high cure rates. RG-101 has the potential to shift the treatment landscape again and broaden options for patients. However, it is still too early to determine whether the treatment will advance beyond the early stages.
While the average viral load drop was 4.1 log, after 29 days only six of the 14 treated patients had no detectable HCV virus. This translates into a rapid virologic response (RVR) rate of 43%, which is low compared with the 80% RVR associated with currently available oral treatments.
Clearly, more studies are needed. Researchers are exploring combination therapy with oral treatments and RG-101, as well as different dosage amounts. And of course, they are continuing to assess safety and tolerability along the way.