Mount Sinai Health System's convalescent plasma study is collecting the antibody-rich plasma of people who have contracted the virus and then recovered from it, so they can inject it into critically ill COVID-19 patients. (Envato)

Doctors trialing an experimental antibody treatment in the fight against coronavirus are reportedly turning away gay men whose blood could help save lives.

Mount Sinai Health System in New York City, USA, is collecting the antibody-rich plasma of people who have recovered from coronavirus, so they can inject it into critically ill COVID-19 patients in a bid to stimulate their immune systems.

But although their precious antibodies could save lives, doctors are turning away gay men, as well as anyone taking PrEP, who are offering to donate.

New York man had donation cancelled just hours before his appointment.

Sabri Ben-Achour, 39, began experiencing symptoms of coronavirus on March 12, according to NBC News.

He suffered with a fever, aches, fatigue, cough and headache for around 36 hours before beginning to feel better, although he said his sense of taste and smell was “gone”.

Ben-Achour was sure he had contracted COVID-19, but was not able to get tested because he was not considered seriously ill.

He later saw an advert for Mount Sinai Health System’s convalescent plasma study and decided to apply.

The New York City resident was asked about his medication (he takes PrEP) and symptoms, and had his blood drawn. It was then confirmed that he had recovered from coronavirus.

He said he was told by doctors that his plasma had a “robust” number of antibodies, and they needed his donation as soon as possible to begin helping people with the experimental treatment.

But just a few hours before his donation appointment, they reportedly changed their minds.

Gay man rejected from coronavirus study because of blood ban.

Because plasma comes from a blood donation, Ben-Achour was subject to the blood donation restrictions for men who have sex with men.

In the US, men who have sex with men cannot donate blood unless they have been celibate for at least a year. This rule was put in place in 2015, before which gay and bisexual men could not donate at all.

Ben-Achour said he was told he would have to stop having sex and stop taking PrEP for a year before he could donate.

He said he would be happy to go off of the drug for four weeks, “but obviously not for a year — that would be putting myself in danger”.

The New York Blood Center, which declined to take his blood, told NBC it was following federal and industry guidelines.

Blood ban on men who have sex with men hampering coronavirus efforts.

As well as needing the valuable antibody donations, health services in the US are running low on blood donations since blood drives have been cancelled because of the coronavirus pandemic.

According to the American Red Cross, since the coronavirus began 2,700 blood drives have been cancelled, resulting in 86,000 fewer blood donations.

Last week, 17 senators told the Food and Drug Administration (FDA) in a letter that it needs to change AIDS-era restrictions on queer men giving blood in order to meet increased transfusion demands.

The senators, including Bernie Sanders and Elizabeth Warren, said in a letter: “We need to shift away from antiquated and stigmatising donation policies to ones that are scientifically sound, based on individual risk, and inclusive of all potential healthy blood donors.”

A recent study showed that there had been zero increase in HIV infections from donated blood in the United States after the previous lifetime ban on gay and bisexual male donors was lifted.