After failing to get a response from the Food & Drug Administration (FDA), Massachusetts Senator John Kerry has drafted a second letter asking the agency to justify its lifetime ban on blood donated by gay men.

Seventeen Democratic lawmakers joined Kerry last Thursday in asking FDA Commissioner Margaret Hamburg to reverse the policy.

Instead, the agency quickly issued a statement to the press, stating that the ban “is based on current science and data.”

Kerry said he was “surprised to discover that, rather than respond to our letter, the FDA apparently immediately released a statement to the press dismissing our call for a review,” in his second letter to Hamburg issued Tuesday.

“We did not write to the FDA to defend the people's desire to donate blood,” he added. “Please share with us the current science and data referenced in your statement used to continue to justify this policy.”

In the original letter, the lawmakers argued that the ban specifically singles out gay men and is “scientifically unsound” in asking for its end.

“Prospective donors who have engaged in heterosexual sexual activity with a person known to have HIV are deferred for one year. At the same time, male donors who engaged in protected homosexual sexual activity with a monogamous partner 26 years ago are deferred for life.”

“The ban also does not distinguish between safe and unprotected sexual activity. As a result, healthy blood donors are turned away every day due to an antiquated policy and our blood supply is not necessarily any safer for it.”

The policy, which rejects men who have had a sexual relationship with another man since 1977 from donating blood, is unnecessary because of technological advances, the lawmakers said.

“We live in a very different country than we did in 1983. Today, the high-risk behaviors associated with HIV contraction are more fully understood and dramatic technological improvements have been made in HIV detection. … As a result [of screening], the blood banking community believes that the lifetime deferral is no longer necessary to protect the integrity of the blood banks.”

In addition to Kerry, the letter was also signed by Democratic Senators Kirstin Gillibrand of New York, Dick Durbin of Illinois, Daniel Akaka of Hawaii, Sheldon Whitehouse of Rhode Island, Sherrod Brown of Ohio, Frank Lautenberg of New Jersey, Bob Casey of Pennsylvania, Bernie Sanders of Vermont, Russ Feingold of Wisconsin, Mark Udall of Colorado, Al Franken of Minnesota, Maria Cantwell of Washington, Carl Levin of Michigan, Tom Harkin of Iowa, Mark Begich of Alaska, Roland Burris of Illinois and Michael Bennet of Colorado.