An HIV-preventative drug has been the subject of a legal battle over which organisation should pay for it. As campaigners win their High Court case against the NHS, one man tells how taking the medication has changed his life.
To look at, pre-exposure prophylaxis (Prep for short) is a small, blue pill - but it's caused a big controversy.
The drug is not currently available on the NHS - and an NHS England decision to that effect has caused a well-documented outcry from charities and campaigners alike.
However, about 500 homosexual men in England - who form part of a trial called Proud - have been taking it for years while experts monitor its effects.
Harry Dodd is one of those men.
He was invited to take part in the trial after doctors identified him as a "high risk" sexually active gay man. However, as he explains, the requirements for being judged as such were, in his words, "surprisingly low".
"They asked me if I'd had sex without a condom within the last three months, I said 'yes' and then they asked me if I was likely to have sex in next three months and again I said 'yes' - and that's all it takes to be 'high risk'," he said.
And so, in 2013, Harry started taking Prep and he has remained HIV negative ever since, despite having unprotected sex.
Taking Prep protects cells in the body, which are then able to stop the HIV virus from multiplying - should they be exposed.
Critics of Prep claim that allowing the drug to be freely available on the NHS would promote promiscuity and leave people more vulnerable to other sexually-transmitted infections.
But Harry - who in the past has had near misses with HIV - vehemently disagrees with this view.
The 25-year-old says the drug has allowed him to grow in confidence and he goes further, believing it could bring the gay community closer together and stop discrimination against those who are HIV positive.
"People need to understand the visceral fear HIV invokes," he explains.
"I remember when I was younger going for an HIV test and at the time I was living in a tower block. The thought fleetingly crossed my mind 'well at least I can chuck myself off the balcony if it's the wrong result'.
"I've seen the panic on the face of previous boyfriends when they are awaiting their results - it's a huge fear and it affects everything you do.
"To be able to have sex without having that fear hanging over you all the time is huge."
Taking Prep means the chances of contracting HIV, even if you sleep with someone who is HIV positive, are greatly reduced.
There are more than 100,000 people living with HIV in the UK and, statistically, gay men are the most at-risk group.
The average HIV prevalence in the UK is 2.3 per 1,000 population. However for gay men the rate jumps to 48.7 per 1,000. Black African women are the second most at-risk group with a prevalence rate of 43.7 per 1,000.
Latest figures show there were 6,151 new diagnoses made in 2014, up from 6,032 the previous year, according to Public Health England.
And in London, one in eight gay men has HIV.
'I kept it to myself'
Harry, who works for a town planning consultancy in London, can recall a time when he believes he came perilously close to getting HIV.
"On Christmas Eve 2012, I was getting off the train in Liverpool to visit my family.
"The night before I'd slept with someone I'd been seeing, he was someone I trusted.
"But for the first time we didn't use a condom. As I approached the station he messaged me asking about my status.
"I informed him I was negative and in response he said I should go to A&E - he was positive and recently diagnosed.
"I kept it to myself, filled with overwhelming anxiety, fear and shame. How could I tell my friends and family the truth? It would disappoint them.
"That situation filled me with mixed emotions... anger both at myself for not insisting on using protection and at him that he hadn't told me before the event, but also relief and thanks that he had told me at all.
"I was confused over whether to blame, empathise or comfort him. Emotions that tore our friendship apart, tore me apart and continue to tear communities apart."
Harry swiftly took himself to A&E, where he was given drugs to treat exposure to HIV and fortunately tested negative for the virus subsequently.
But the threat for gay and bisexual men is very real and the results from the Proud trial - in which Harry is a participant - are promising.
The trial took about 500 "high risk" gay men and split them into two groups.
The first group took Prep straight away, while the second acted as a control group and waited for 12 months before taking the drug.
In that control group, 20 people contracted HIV during those 12 months.
But in the immediate Prep group only three people contracted HIV and in each case the reason for contracting the virus can be explained. One person was found to already have HIV before the trial started and the other two people both stopped taking the drug for a considerable amount of time.
The early results were so significant that Prep was given to all participants before the end of the 12-month period on ethical grounds.
"The results from the trial are proof that this drug is working," says Mitzy Gafos, who is a social scientist working in the clinical trials unit at University College London.
However, she also said that early indications from the trial's relatively small sample size show those taking the drug were more inclined to have different sexual partners, although the incidence rate of sexual infections was not increasing.
But despite these results, the route to getting Prep available on the NHS has also been fraught with controversy.
In the 18 months up until March, NHS England had been following a process to decide whether the drug should be available to people at high risk of HIV, on the NHS.
But in March there was uproar from charities and campaigners when NHS England said it was abandoning this process and HIV prevention was not its responsibility.
After initially saying it would "consider" its position in May it confirmed it would not be commissioning Prep, arguing that it does not have the legal power to do so.
Harry believes everyone should have access to Prep - which costs around £450 a month to buy privately.
The Proud trial is also drawing to a close in the coming months and the men who are on it, who have been used to taking the drug for three years, now face the prospect of having to buy it privately from other sources - chiefly pharmaceutical companies in India.
Harry says taking Prep has still not become socially acceptable.
"Too many people seem to think it will encourage a hedonistic lifestyle, but for me this is about saving lives," he says.
"People reacted with cynicism when the contraceptive pill for women was first introduced.
"Taking Prep has helped me to trust again, have relationships and build bridges and that shouldn't be taken away."
His view is also one shared by leading health officials.
Jim McManus and Dominic Harrison, both directors of public health, recently wrote a joint piece in the British Medical Journal calling for Prep to be made available to all.
They described NHS England's decision not to, as "an incoherent national approach to HIV prevention".
NHS England has said it will provide £2m over the next two years to research how Prep "could be commissioned in the most clinically and cost effective way".