Now that Gilead Sciences has made large profits developing highly effective treatments for hepatitis C virus (HCV), the pharmaceutical company has set its sights on curing two more viral epidemics—HIV and hepatitis B virus (HBV), Bloomberg Business reports.

Since hep C drug Sovaldi (sofosbuvir) became available in 2013 followed by Harvoni (ledipasvir/sofosbuvir) in 2014, Gilead has more than doubled its annual drug sales overall, leaving the company with about $8.61 billion for further investments.

A step in that direction is rolling out an improved version of Viread (tenofovir disoproxil fumarate, or TDF). Viread starts facing generic competition in December 2017. The updated drug uses tenofovir alafenamide, or TAF, which achieves viral suppression with just one-tenth of the dose of TDF, while doing far less damage to bones and kidneys.

Gilead is also putting additional funds toward studying one of its leading candidates for an HIV cure—a drug called GS-9620—which is currently undergoing human trials. The drug employs a promising new “kick and kill” strategy to help the immune system recognize and destroy HIV in the blood, which could lead to a functional cure.

GS-9620 is also being developed as a potential cure for hep B, after early animal trials demonstrated undetectable viral loads in HBV-positive woodchucks after just four weeks of treatment with the drug.

Despite the potential, health experts caution that Gilead faces long odds in curing HIV or hep B any time soon.