Using expensive new antivirals to treat hepatitis C in prisoners makes fiscal sense, a new paper says.

Based on computer models, new pricey drug combinations were more cost-effective than older drug combinations and no treatment at all, researchers found.

“Essentially what our model does is follow a hypothetical cohort of prisoners that looks like a prison population in the U.S.,” Jeremy Goldhaber-Fiebert told Reuters Health.

“It allows us to ask a variety of ‘what-if’ questions and probe how sensitive our findings are to various factors,” said Goldhaber-Fiebert, the study’s senior author from Stanford University in California.

The CDC says about 3.2 million people in the U.S. are infected with the chronic disease. Goldhaber-Fiebert and his colleagues wrote October 20 online in Annals of Internal Medicine that about 500,000 incarcerated people have hepatitis C.

Until recently, the virus was treated with a combination of interferon and ribavirin, which had to be taken for about a year, caused flu-like symptoms, and was only effective in a minority of patients.

The U.S. Food and Drug Administration (FDA) approved Merck’s Victrelis (boceprevir) in 2011 to be added to the existing combination of drugs. The new combination made the treatment more effective - and more expensive (see Reuters story of May 13, 2011 here: reut.rs/1yg9GGm).

Then, the FDA approved Gilead’s Sovaldi (sofosbuvir) in 2013. The drug is taken for 12 weeks and cures a majority of patients but comes with a price tag of $84,000 (see Reuters story of December 6, 2013 here: reut.rs/1ygcAuT).

Insurers have pushed back against the price of the new medication (see Reuters story of May 20, 2014 here: reut.rs/1ygfGPx).

Using their model, the researchers compared prisoners who received 12 weeks of Sovaldi plus the interferon and ribavirin, prisoners who received 28 weeks of Victrelis plus the two older drugs, and prisoners who did not receive treatment.

They examined costs of treatment in terms of quality–adjusted life years (QALY).

Overall, they found the combination of Sovaldi and the original drugs added 2.1 QALYs at a cost of about $54,000, compared to no treatment.

The combination including Sovaldi cost about $25,700 per QALY gained among prisoners serving short sentences and about $28,800 per QALY gained among those serving long sentences. The difference in cost can be partially attributed to various factors, including the increased risk of reinfection among people still in prison, Goldhaber-Fiebert said.

In either case, he and his colleagues found the Sovaldi-based combination of drugs to be less expensive per QALY than the Victrelis combination.

However, there are other challenges when choosing a hepatitis C treatment for prisoners, the researchers write.

For example, treating U.S. prisoners with the Sovaldi combination may come at an upfront cost exceeding $30 billion to the prison systems. The cost benefits may not be realized until the prisoners are released on another healthcare system like Medicaid.

“Most people in will be out,” said Dr. Anne Spaulding. “We’re looking at a disease that will take 30 years to progress. A lot of hepatitis C that we’re not treating in the prison will end up being very costly not just for patients who are on Medicaid, but patients who do not have Medicaid who present to emergency rooms. Someone will have to pay.”

Spaulding, who wasn’t involved with the new study, is an expert on hepatitis C infections among U.S. prisoners. She’s an assistant professor at Emory University’s Rollins School of Public Health in Atlanta.

The U.S. Federal Bureau of Prisons currently recommends Sovaldi for many prisoners with hepatitis C infections.

“I think the key message would be to those who control state budgets,” said Spaulding. “There are benefits to considering the health of future taxpayers, future citizens and people returning to the community. There are benefits to treating hepatitis C while they’re incarcerated.”

“The group that can have the most affect on increasing the new infections of hepatitis C is actually the injection drug users,” she said. “If you can get rid of the hepatitis C while they’re in prison, they can’t spread hepatitis C when they’re in the community.”

“It’s a message that needs to go to the decision makers who control the purse strings,” she said, adding that this is especially true for people who control state budgets.

Goldhaber-Fiebert said prisons and jails in the U.S. should give careful consideration to the hepatitis C treatment for the population that they provide services to.

“High-cost treatments can also be high-value if they deliver substantial enough value,” he said.