Wednesday, August 19, 2015

Do restrictions on sofosbuvir for HCV harm or protect the vulnerable?

Accusing Anthem Blue Cross of denying them access to a "cure," plaintiffs with hepatitis C infection have filed a class action lawsuit against the health insurer for restricting coverage of sofosbuvir (Sovaldi), an antiviral drug that costs $84,000 in the U.S. for a single 12-week course of treatment. Although the medical criteria that Anthem uses to determine if patients are eligible to receive sofosbuvir are complicated, they basically boil down to limiting access to patients with proven liver damage, demonstrated by advanced fibrosis or cirrhosis. Most HCV-infected patients, who have no or minimal liver damage, do not meet these criteria but understandably want to receive "lifesaving" treatment too.

Public insurance programs have also been struggling to prevent sofosbuvir from busting their limited budgets. In June, a Health Affairs blog post discussed the potential consequences to Medicare Part D spending if even a fraction of the estimated 350,000 Medicare beneficiaries with HCV receive sofosbuvir. And this month, an analysis and related CDC review published in the Annals of Internal Medicine found that three-quarters of state Medicaid programs, like Anthem, pay for the drug only for HCV patients with advanced fibrosis. More than half restrict sofosbuvir prescribing to liver specialists and/or require a 1 to 12 month period of abstinence from illicit drug or alcohol use prior to treatment. Arguing that these restrictions may violate federal Medicaid law, the authors conclude:

None of the restrictions on sofosbuvir coverage detailed here seem to meet the criteria for permissible restrictions. Although the price of new therapies creates financial challenges for federal and state Medicaid budgets, decisions for prioritizing patients for more immediate therapy should be based on clinical criteria and medical evidence. It is recommended that the restrictions be removed; apart from potentially being a human rights violation, they do not make (economic) sense in terms of clinical, public, and long-term health.

But are restrictions on sofosbuvir coverage purely about health equity and human rights, as the Annals pieces assert, or are other ethical issues in play? First, is sofosbuvir really a cure? Unlike a vaccination, it does not prevent HCV re-infection, which occurs in a non-insignificant proportion of patients who continue intravenous drug use after successful treatment. Second, sofosbuvir is only proven to produce undetectable HCV viral loads after 12 weeks, and it is a huge leap of faith to assume that this surrogate marker of "cure" will definitely translate to less liver faillure or improved mortality. Finally, only 10 to 20 percent of persons with HCV will develop cirrhosis or hepatocellular cancer up to 30 years after becoming infected. For the 80 to 90 percent who don't, sofosbuvir can only cause harm: inconvenience and financial harm, to be sure, plus the potential for rare but serious adverse events.

Advocates of widespread sofosbuvir use have portrayed the coverage debate as one about rationing based on cost. But I don't think I would favor treating most healthy persons with HCV if the drug cost a dollar a dose, rather than $1000. A patient with fibrosis has headed far enough down the path to poor health outcomes that I am willing to overlook the gaps in the evidence on sofosbuvir's benefits, since it's unlikely that treatment would be worse than the alternative. It's not nearly as easy to disregard the uncertainties about benefits and harms for someone who is not ill from HCV and may never be. By accounting for a patient's current clinical status, limits on sofosbuvir prescribing are as likely to protect vulnerable patients as to harm them. On the contrary, insurers that have not put such restrictions in place may be encouraging potentially unethical prescribing.

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