Pre-exposure prophylaxis (PrEP) is a daily tablet- proven to prevent those taking it from contracting HIV. The drug contains two medicines, tenofovir and emtricitabine, which are also used to treat HIV infection. When taken each day at the same time, the drug provides a 92% – 99% reduction in HIV risk to those taking it.

However, England lags far behind the rest of the UK when it comes to PrEP. The drug is only accessible through the NHS Impact Trial, which launched at the end of 2017 and currently has the capacity for 26,000 total participants. NHS England supplies the drug to various participating local authorities, which ultimately control how the drug is distributed. Outside of England, PrEP is freely available for patients in Scotland and Wales.

According to the BBC, PrEP costs the NHS about £11 per patient, per month, but costs patients upwards of £30 a month should they decide to go private. In contrast, the antiretroviral drugs an HIV+ patient has to take costs the NHS between £100 and £500 per month per patient.

At least 15 people in England have now tested positive for HIV while waiting for a place on the Impact Trial, and commentators fear this may be just the tip of the iceberg. Several of these people were reportedly on low incomes and could not afford the drug privately. Had they lived elsewhere in the UK, they would have been able to obtain the drug from their GP or a local sexual health clinic.

Research by UK online doctor Zava has also found that 23% of trial sites are no longer accepting any more gay or bisexual men at all, with the remaining spaces available specifically reserved for patients from other high-risk groups.

Zava clinical lead for service expansion Dr Babak Ashrafi said: “High-risk heterosexual groups do not tend to know about PrEP or engage with health services as well as men who have sex with men, so there are a higher proportion of available spaces for these groups.”

National guidelines recommend PrEP for men who have sex with men and transgender women who have anal sex without using a condom. PrEP is also recommended for patients of other demographics if they have an HIV-positive partner who does not have an undetectable viral load, which occurs when antiretroviral treatment has reduced the quantity of the virus in their body to such low levels they can’t pass it on.

Recent migration to the UK and diagnosis of a recent rectal sexually transmitted infection (STI) are also factors that can be used to determine a patient’s eligibility for PrEP.

The drug’s efficacy is long established and the Impact Trial is taking place under the guise of assessing various logistical queries surrounding the distribution of the drug in England.

These include finding out how many people who attend sexual health clinics are at high risk of HIV, and thus eligible for PrEP, how likely people offered the drug are to accept it and how long they tend to use the medication for, as well as the impact of HIV and other STIs on the population.

But for patients at risk of HIV, a postcode lottery that makes the drug available through certain NHS jurisdictions and not others can be incredibly frustrating.

Daniel Bowen, a patient who attempted to access PrEP through the Whittall Street Umbrella Clinic, says: “I was told they would let me know if the trial was extended further – or if PrEP became more widely available on the NHS. Other than that, it will just be luck and how quickly I can get an appointment if they announce more trial spaces.

“I’m not working and can’t afford PrEP myself so I’ve had to learn to trust the men I have sex with, rather than being able to take the preventative measure myself. I know it might not make sense for people who don’t live the kind of lifestyle I do, but this is me feeling like I can’t do things I want to do, or participate in part of a gay subculture I identify with, because the risk is higher than it should be and I can’t predict my own behaviour in high-risk situations.”

So, why is the Impact Trial even taking place when PrEP’s efficacy is already established?

British HIV Association (BHIVA) chair Dr Laura Waters says: “PrEP is indeed very efficacious at preventing HIV, but at the time that was established Truvada, the branded version of the drug used for PrEP, was very expensive. By undertaking a trial we were able to use the much less expensive generic version of the drug.”

Truvada is manufactured by pharmaceutical giant Gilead, which has long been under fire from HIV activists over its drug patents. When the European patent on Truvada expired in June 2017 the drug cost around €400 for 30 tablets across the continent. Gilead then attempted to extend the drug’s patent with a supplementary protection certificate (SPC).

SPCs are issued to compensate for delays to the marketing authorisation of drugs, and apply for 15 years after the date of first market approval, meaning Gilead would have had protection from PrEP-based competition until 2020. A group of generics manufacturers, including Accord Healthcare, swiftly began challenging Gilead’s protection against generic competition in court.

Different healthcare systems, such as NHS Scotland, took the risk of making generic PrEP freely available via GPs and sexual health clinics when the court case between Gilead and the generics manufacturers was still ongoing.

NHS England could have followed suit, but instead chose to offer patients a generic version of the drug through the Impact Trial. This removed the risk of legal action from Gilead, as supplying a generic version of a patent-protected drug is deemed acceptable in the context of a clinical trial, but meant it couldn’t be distributed as freely.

England’s High Court ruled the SPC invalid in September 2018, on the basis that is was not protected by the basic patent, but at this point, the Impact Trial was well underway. As such, Impact is a partial vestige of historic patent law. PrEP’s reach in England is limited due to past decisions of regional healthcare bodies.

Clinics need to have the resources in place to support patients on PrEP throughout their treatment. People on PrEP still need to be tested for HIV and other STIs every three months and undergo intermittent kidney checks, alongside assessments of their ongoing HIV risk and the opportunity to talk about other methods of risk reduction.

Waters says: “Sexual health clinics have faced significant funding cuts so the trial is also about the feasibility of offering PrEP in real-life via the already over-stretched services.”

The local authority public health budget in the UK has been cut by £700m in real terms between 2014/15 and 2019/20, which has led to sexual health service budgets being cut slashed 25%. Meanwhile, demand for sexual health services rose by 15% between 2014 and 2018 and rates of STIs such as syphilis and gonorrhoea are skyrocketing. Alongside a patent law hangover, the trial exists to assess whether supplying PrEP to patients who need it is financially feasible under austerity.

In October 2019, the government announced that the local authority public health grant would increase by 1% in real terms in 2020-2021, but this is unlikely to make a substantial difference to the funding of sexual health services.

Terrence Higgins Trust PrEP lead Mark Lewis says: “We need to ensure that public health services – including sexual health services – are fully funded to meet local need, in order to tackle the soaring rates of STIs and to end new HIV transmissions by 2030.”

The Impact Trial is due to end in August 2020. The Department of Health says that work is underway to plan for a ‘seamless transition from the trial to routine commissioning’, but it’s currently unclear how exactly that will transpire and there are concerns that progress on working towards routine commissioning of PrEP is occurring too slowly.

“It's likely the current model will be upheld for some time initially, with a strict inclusion criteria and secondary care ownership,” says Babak. “The only thing that is likely to change is that there won't be any limits on spaces at any sexual health clinic if you're eligible.”

While this discussion is purely speculative, the situation Babak describes would mean that patients who are unable, or unwilling, to attend follow-up appointments at a clinic on a regular basis would still be unable to access PrEP. It also means those who might want the reassurance of the drug but who don't fully fit the eligibility criteria may find themselves turned away from NHS services.

In the meantime, patients at risk of HIV aren’t about to collectively alter their lifestyles until the drug becomes freely available. Limited access to PrEP has left them vulnerable to acquiring an easily preventable chronic disease, and struggling to accept that expired drug patents and a lack of resources are supposed to make this justifiable.

Bowen says: “We have enough evidence that PrEP is reducing the number of new diagnosed cases of HIV, and quite frankly that alone should be enough to motivate the NHS to fund the drug for anyone who wants it.”

As Democratic candidates jockey for position in the campaign to win their party’s nomination in the 2020 US presidential race, healthcare has emerged as a central theme. With public fury over prescription drug costs building to a head and President Donald Trump’s sound and fury on the issue ultimately signifying next-to-nothing on pricing, the Democratic primary candidates are taking the opportunity to set out their stalls on healthcare. By doing so, each hopes to be able to give the President a bloody nose in the run-up to the election in November by criticising his perceived inaction on lowering drug costs and presenting a credible alternative vision.

The candidates’ healthcare proposals converge on many issues and part ways on others, and there are still plenty of unanswered questions around the costs of the more radical plans, and whether the more conservative pitches do enough to address the inequities of US healthcare.

Mayor of South Bend, Indiana and dark horse primary candidate Pete Buttigieg announced his own healthcare plans in October under the banner of ‘Affordable Medicine for All’. As well as common proposals, such as allowing the government to negotiate prices for Medicare and capping out-of-pocket costs for patients, Buttigieg has also proposed a new tax scheme to punish drugmakers that refuse to renegotiate the price of high-cost drugs. Under the proposal, companies that won’t renegotiate prices or leave negotiations without agreement will be hit with a 65% tax on gross sales of the drug in question, rising by 10% every quarter to a maximum of 95%.

The US pays between three times and twice as much as European Union (EU) countries for drugs according to data from the Commonwealth Fund.

There are many good ideas being proposed by this year’s crop of Democratic candidates to reform a healthcare system that clearly isn’t working for many Americans. But, this isn’t one of them.

While the economic realities of Sanders and Warren’s ‘Medicare for All’ plan are still being debated – with Buttigieg arguing that it would involve a tax hike on middle-class Americans – they still provide some measure of certainty about the rules of the game under the new system, especially with a lengthy transition period.

Like many other countries in Europe and elsewhere, the US - under a public insurance system - would be able to negotiate drug prices using the leverage that comes with control over market access. The price-cutting benefits of a large public entity negotiating with pharma companies have been proven the world over, most recently in China, which in November announced that the prices of 70 blockbuster drugs had been reduced by an average of 61%, with the companies involved accepting the cut in exchange for inclusion on the medicines list of China’s massive state-run health insurance system. The promise of market access, rather than the threat of heavy taxation, prompted these cuts.

Buttigieg’s punitive tax measure provides none of this certainty, and the threat of implementing massive taxes that would essentially make it pointless to keep selling a drug in the US risks turning price negotiations into a form of corporate bear-baiting. While Americans are used to paying the world’s highest drug prices, they are also used to being the first to access the industry’s most innovative treatments – aggressive taxation is one of the best ways to reverse that trend.

The candidate’s health policy document notes that the first drugs to face negotiation will be “those with very high price tags and large price differences between what we pay and what other industrialised countries pay”, and that the federal government will be required to negotiate at least 25 drugs a year. This creates a huge amount of uncertainty in the industry about which drugs will be first on the chopping block, while the 25-renegotiations-a-year quota seems an arbitrary number rather than one based on evidence.

There’s no doubt that change is in the air for American healthcare, which is the most expensive in the world without the superior outcomes to match. But by focusing on slapping perceived offenders with impractical taxes, Buttigieg misses the point. Measures taken earlier in the process, such as patent reform, incentivising generic competition and bolstering the negotiating power of federal payers – all of which are endorsed by Buttigieg along with other candidates – have the power to reduce prices while maintaining a predictable marketplace in which the industry can operate. This confrontational tax plan isn’t needed, and smacks more of political point-scoring than sensible policymaking.