he leading candidate to become the world’s first Covid-19 vaccine, developed by the US pharmaceutical company Pfizer and Germany’s BioNTech, had its genesis in late January 2020. Uğur Şahin, chief executive of the Mainz-based biotech, read about coronavirus in the Lancet and worried that the outbreak could grow into a pandemic. Şahin summoned colleagues to tell them that the company would shift its focus from cancer treatments to finding a vaccine for the deadly virus. It would use a method based on mRNA, whereby a stretch of genetic material from the coronavirus is injected into the body, resulting in human cells producing its so-called spike protein. This in turn triggers an immune response. Pfizer stepped in to help with development and distribution costs. Last Monday (9 November), the two companies surprised the world with news that in global trials the vaccine had been 90% effective in protecting people from the virus, raising hopes that an end to the pandemic could be in sight – and sending global stock markets soaring. Pfizer boss Albert Bourla, who sold $5.6m (£4.3m) of shares on the same day, called it “the greatest medical advance in the last 100 years”. After further tests, the firms plan to submit the vaccine for emergency regulatory approval later this month, and it could be shipped around the world by December. Global sales could reach $13bn next year, evenly split between the two companies, according to estimates from investment bank Morgan Stanley. Other vaccines are not far behind in development. Normally, it takes more than 10 years to develop a vaccine, at a typical cost of between $500m and $1.2bn. Vaccines generally have a 6% chance of making it to market, according to the International Federation of Pharmaceutical Manufacturers and Associations (IFPMA). The Covid-19 pandemic, which has killed more than a million people, sparked a global race to find a vaccine, and 10 are now in late-stage clinical trials. Gavi, an alliance of public and private bodies that aims to increase immunisation in poor countries, is behind the Covax facility, a fund for future Covid-19 vaccines. Its managing director, Aurélia Nguyen, said: “This is quite unprecedented. Nothing like it has ever been attempted. We are doing this many times faster than has ever been done before.” She said there had been a large international effort, with governments and health organisations pre-ordering hundreds of millions of doses from vaccine makers. Steps that are normally taken sequentially had been carried out in parallel, including manufacturing doses without knowing whether the vaccine works, and submitting regular clinical data to regulators during trials with tens of thousands of volunteers, rather than at the end of the process. Emily Field, head of European pharmaceutical research at Barclays bank, said the pharma industry had a head start after the 2003 Sars and the 2012 Mers epidemics – both caused by coronaviruses – and had already been working on mRNA technologies, which can be adapted to different viruses. US biotech firm Moderna said it would know by the end of November whether its vaccine, which also relies on mRNA technology, works. In the UK, AstraZeneca and the University of Oxford, whose vaccine is based on a modified chimpanzee cold virus, expect to have final data by the end of the year. Vaccines from US firms Johnson & Johnson and Novavax are also in late-stage clinical trials, as are Russia’s Sputnik vaccine and a CoronaVac vaccine from Chinese biotech firm Sinovac. France’s Sanofi Pasteur and the UK’s GSK, the world’s biggest vaccine-maker by sales, are collaborating on a vaccine that is expected to be ready next summer. Governments and other public organisations have poured more than $12bn of development and manufacturing funding into the six frontrunners in the western world, according to Médecins Sans Frontières (MSF). While Pfizer has not had any research funding from the US government, its German partner had €475m from the German government and the European Investment Bank, and the US government agreed to pay nearly $2bn for production and nationwide delivery of 100 million doses. Gavi said on Friday that it had raised more than $2bn from governments and the Bill & Melinda Gates Foundation to fund Covid-19 vaccines for low- and middle-income countries, but that at least $5bn more would be needed next year. The speed with which these vaccines are being developed has raised concerns that trials may have been rushed and corners cut. However, experts say the candidate vaccines have been tested for safety and efficacy in large international trials, and that drug regulators can be trusted. Kate Elder, a senior vaccines policy adviser at MSF, said: “We can trust these stringent regulatory authorities to complete the necessary checks and balances to ensure safety.” The history of vaccines started with one against smallpox, introduced by Edward Jenner in 1796, after he observed that milkmaids who had previously had cowpox did not catch smallpox. Jenner took material from a cowpox sore on a milkmaid’s hand and injected it into the arm of his gardener’s nine-year-old son. Almost two centuries later, in 1980, the world was declared free of smallpox. For years, the development of new vaccines has been in the hands of a few big pharmaceutical companies – Merck, Pfizer, Johnson & Johnson, GSK and Sanofi. But a number of local firms, such as India’s Serum Institute, produce vaccines more cheaply. Vaccines tend to be more difficult to manufacture than traditional drugs: setting up the necessary hermetically sealed facility costs between $10m and $100m, according to the IFPMA. And because many childhood vaccines are administered only once and last a lifetime, the global vaccines market, with sales of $32.5bn last year, is small in comparison with the pharmaceuticals market of $880bn, according to Evaluate Pharma. About 116 million children are vaccinated worldwide every year, according to the World Health Organization [WHO], and this helps prevent up to 3 million deaths. The price of vaccines varies widely. A dose of simple tetanus vaccine can cost as little as 3p in poorer countries, while a dose of the six-in-one vaccine DTaP-HepB-Hib-IPV – given to young children to protect against diphtheria, tetanus, pertussis, hepatitis B, polio and Haemophilus influenzae type B (Hib) – can cost $92 in the US. Viagra-maker Pfizer’s bestselling product last year was its pneumonia vaccine, Prevnar 13, which brought it annual revenues of nearly $6bn. The vaccine costs around $227 per dose in the US, and four shots are required. Pricing for the future Covid-19 vaccines ranges from AstraZeneca’s $3-$5 a dose and Johnson & Johnson’s $10 – on a not-for-profit basis guaranteed for the current pandemic – to Pfizer’s $19.50 a shot and Moderna’s $37. A separate issue is rising vaccine scepticism around the world. Elder at MSF said: “In 2019, the WHO named vaccine hesitancy as one of the top 10 threats to global health. Here in the US, a recent poll showed that more than half of people said they wouldn’t take a Covid-19 vaccine.” But tackling scepticism will be a future concern: governments desperately need viable vaccines first.