Sovaldi, a drug that can cure ninety percent of the people suffering from hepatitis C, costs $1,000 per pill. A Senate committee is asking the manufacturer, Gilead to explain why the price for the drug is so high.

The treatment for the Hepatitis C virus (HCV) was discovered by Pharmasset, a new Jersey-based pharmaceutical company. It was later developed by Gilead sciences, a bio-technology company that specializes in commercializing therapeutic medicines.

Chuck Grassley, Republican senator from Iowa, joined with Democrat Ron Wyden of Oregon in writing a letter to John Martin, the Chief Executive Officer (CEO) of Gilead. The statement asks the corporate executive to detail the high cost of the drug within 60 days. Each of the lawmakers is a member of the Senate Finance Committee.

"It is unclear how Gilead set the price for Sovaldi. That price appears to be higher than expected given the costs of development and production and the steep discounts offered in other countries. An efficient market needs informed consumers to keep costs down" the lawmakers wrote in the letter to Martin.

Millions people in the United States are infected with HCV. At $84,000 a treatment, the cost of Sovaldi could greatly impact the Medicaid and Medicare programs. Roughly one-third of the people suffering from hepatitis C are housed in prisons and jails around the country.

Sovaldi, also called sofobuvir, was approved for use by the Food and Drug Administration (FDA) in December 2013. It was the first treatment shown to be safe and effective in the treatment of HCV without accompanying doses of interferon. Just two weeks before that approval, the FDA allowed the prescription of another drug for hepatitis C, Olysio or simeprevir.

The statement asks Gilead management to show any transcripts, spreadsheets, emails or other data that demonstrate how the company arrived it its retail cost.

"Hepatitis C is a viral disease that causes inflammation of the liver that can lead to diminished liver function or liver failure. Most people infected with HCV have no symptoms of the disease until liver damage becomes apparent, which may take several years," FDA researchers wrote in a press release announcing approval of the drug.

Patients prescribed the medication need to take one pill a day for over two months. "Gilead will offer the drug in other countries for a fraction of the [U.S.] price. In Egypt, for example, Sovaldi could be offered for as low as $900 per course of treatment," the senators wrote.

Amy Flood, spokesperson for the pharmaceutical company, said her organization will comply with the request from the senators.