The number of veterans treated for hepatitis C virus (HCV) by the Veterans Health Administration (VA) surged along with cure rates after the recent U.S. Food and Drug Administration (FDA) approvals of numerous highly effective direct-acting antivirals (DAAs).

Researchers analyzed data on the approximately 79,000 veterans who received 105,000 treatments for HCV from the VA between 1999 and 2015. About 57,500 were cured.

The study authors divided their analysis into mini-eras defined by successive advancements in hep C treatments, including the introduction of: interferon, 1999 to 2000; pegylated interferon, 2001 to 2010; first-generation DAAs Victrelis (boceprevir) and Incivek (telaprevir), 2011 to 2013; DAAs with much higher success rates, including Sovaldi (sofosbuvir) and Olysio (simeprevir), 2014; and Harvoni (ledipasvir/sofosbuvir) and Viekira Pak (ombitasvir/paritaprevir/ritonavir; dasabuvir), 2015.

During these five time periods, the hep C cure rates among those treated rose from below 25 percent in 1999 to 22 to 37 percent by 2010 to 50 percent by 2013 to 81 percent by 2014 and finally to 91 percent by 2015.

Between 2001 and 2002, the number of people receiving HCV treatment doubled, from 2,725 to 6,680. The annual treatment rate proceeded to peak in 2002 and declined steadily through 2010. The rate rose to 4,900 in 2012 but dropped to 2,610 in 2013. The rate then shot up to 9,180 in 2014 and 31,030 in 2015.

The number of people cured of hep C each year was about 390 between 1999 and 2000, 620 to 2,200 between 2001 and 2010, 1,275 to 2,300 between 2011 and 2013, 7,380 in 2014 and 28,085 in 2015.

During the 2015 VA fiscal year, the agency allocated $696 million to offset the cost of DAAs. During this period, the monthly treatment rates rose ninefold, an effect that correlated largely with the availability of these funds, the study authors concluded.

“The VA is on its way to eradicating most cases of HCV in the next two to three years,” says the study’s lead author, George Ioannou, MD, director of hepatology at the Veterans Affairs Puget Sound Health Care System in Seattle. He says that for similar success to occur outside the VA, insurers need to drop restrictions on who can receive hepatitis C treatment, and the cost of treatment needs to drop substantially.