Democratic members of the Congress have issued a letter to the makers of a drug used to cure hepatitis C to question its very expensive price.

The letter was sent by Henry Waxman of California, Frank Pallone Jr. of New Jersey and Diana DeGette of Colorado. It was addressed to Gilead Sciences, the maker of the drug referred to as Sovaldi.

“Our concern is that a treatment will not cure patients if they cannot afford it,” the congressmen wrote in their letter, as reported by the New York Times. 

On the other hand, Gilead Sciences explained that the price for Sovaldi is the fairest price that they could offer for the drug. The company’s executive vice president for corporate and medical affairs, Gregg Alton, expressed that they are willing to meet with the members of the Congress to settle the issue.

“We think the price is fair,” he said in an interview with the N.Y Times. “It will save the system money long term.”

It is estimated that three to four million Americans are suffering from hepatitis C. If left untreated, it could lead to more serious infections such as cirrhosis and liver cancer. Sovaldi was approved by the Food and Drug Administration in December 2013 and could cure 80 percent of hepatitis C cases in a matter of 12 weeks. This is a higher cure rate using the least amount of time possible. Treatment using Sovaldi was also noted to induce the least cases of side effects.

However, insurers argue that a 12-week treatment with Sovaldi can cost $1000 a pill, and this is very expensive.

“It’s unprecedented that we have a drug that is this expensive that this many patients can benefit from,” Dr. Steve Miller told N.Y Times. Miller is the chief medical officer for Express Scripts, the largest pharmacy benefits manager. “You have a drug that has the potential to break a lot of the payers.”