The cost of Gilead Sciences’ hepatitis C pill Sovaldi is once again under the spotlight with the US Senate Finance Committee requesting detailed pricing information.

Committee chairman Ron Wyden (Democrat) and senior member Charles Grassley (Republican) have written to Gilead chief executive John Martin because “we need a better understanding of how your company arrived at the price for this drug”. Gilead got hold of Sovaldi (sofosbuvir) when it acquired Pharmasset in 2012 for $11.2 billion, which costs $84,000 for a three-month treatment; however, the senators claim Pharmasset planned to “profitably sell” it for $36,000.

They also note documentation from the US Food and Drug Administration about how costs could be much higher for patients needing longer treatments, doubling to $168,000 for Sovaldi alone, and that does not include drugs used in combination treatments. The senators go on to say HCV patients with liver cancer may need 48 weeks of treatment.

The letter goes on to make reference to the fact that Sovaldi will be able for a fraction of price in Egypt - $900 per treatment. They add that the drug could cost Medicare $2 billion in 2014-2015 if just 25,000 patients enrolled on its drug benefit programme (Part D) receive Sovaldi prescriptions.

Sens Grassley and Wyden have made 20 separate requests for documents, covering R&D expenditure to marketing costs and sales forecasts, plus details of pretty much every communication it had with Pharmasset.

That the government has joined insurance companies in criticising Gilead comes as no great surprise. The company and leading lights in the pharmaceutical industry regularly point out that Sovaldi is actually curing HCV and the therapy, plus other C drugs that are moving closer to approval, are preventing expensive hospitalisations and avoiding thousands of liver transplants that cost over $500,000 each.