ECHO Flight transports aid workers and medical supplies to Ebola outbreak in DRC, May 2017. European Commission/Flickr. Some rights reserved.Just when you thought it was safe to go back to the African subcontinent, Ebola strikes back. The World Health Organisation (WHO) confirmed that a new outbreak of the disease had occurred in the Democratic Republic of Congo (DRC) on May 12th. On May 21st, it revealed that a fourth person – one of the 43 believed to have been affected and the 400 now being tracked as potential patients – was believed to have died as a result of the virus.
However, unlike the chaos that surrounded the first Ebola outbreak, the authorities seem largely in control. Despite the significant logistical challenge of getting the right medical help deep into the jungles of the Democratic Republic of Congo, Matshidiso Rebecca Moeti, the WHO Regional Director for Africa says that she is “optimistic” that the outbreak can be halted quickly. She also notes that WHO Africa has learned lessons from the last outbreak to become a “more responsive, accountable, effective and transparent organization”.
And of course, this time, doctors are coming armed with the rVSV-ZEBOV vaccine candidate, developed by pharmaceutical giant Merck. The drug is slated to be 100% effective against one of the five strands of the virus and has demonstrated “compelling results” in previous trials, but it has not been licensed yet. Undeterred by this minor detail, the WHO has 300,000 doses on hand and Moeti has indicated that the WHO “could potentially mount a campaign within a week if all of the conditions are met and personnel, financing and logistics are in place.” And on May 23rd, the DRC submitted a formal vaccine trial protocol to an ethical review board, the first step towards deploying the vaccine.
A damp squib in the fight against Ebola?
Recent reports have cast a long shadow over Merck’s vaccine. Indeed, the US National Academy of Medicine has challenged the methodology of the 4160-patient clinical trial and made the lukewarm statement that while the vaccine “most likely provides some protection to recipients,” the protection “could in reality be quite low”. Not only is the vaccine ineffective against four strands of the Ebola virus, but also it might be altogether useless on people with compromised immune systems (HIV positive) or pregnant women.
Beyond raising questions about the way treatments are developed for infectious diseases with public and private funds, rVSV-ZEBOV’s fate seems to parallel another boom-bust: the experimental drug ZMapp. Despite being one of the most sought-after drugs at the height of the Ebola crisis and seen by many as having already been responsible for saving lives, ZMapp has narrowly missed the statistical threshold that researchers have set to prove the drug’s effectiveness. For this reason, the authors of a study conducted by the National Institute of Allergy and Infectious Diseases concede that ZMapp has probably lost its chance to prove its worth as an Ebola treatment. Therefore, future clinical trials would be better off focusing on “one of a small number of other promising, but unproven, treatments that have emerged since the beginning of the recent crisis.”
Luckily, the Merck vaccine is just one of several candidates now in different phases of development. Among the most promising is GSK’s cAd3-ZEBOV vaccine, with the company touting “very encouraging” findings after the first tests, albeit with the caveat that it will only be available in the second half of 2018. And earlier in May, scientists at New York’s Albert Einstein College of Medicine have also indicated that they have identified two antibodies – ADI-15878 and ADI-15742 – that they believe will be able to thwart the five known Ebola viruses. Johnson and Johnson is developing a 2-dose vaccination approach, while China has also thrown down the gauntlet and is working on the Ad5-EBOV vaccine, based on work done by a Chinese military research unit.
Another promising candidate comes from an unlikely source – Guinea. Russian scientists working in a medical research centre built by the aluminium company UC Rusal in the country have devised a vaccine, the Gam-Evak-Kombi, which claims to be 100% effective. After the recent Ebola outbreak in the DRC, Moscow started shipping the drug to Guinea in case the DRC outbreak expands.
States to the rescue
With so many vaccines in the works, one would be forgiven for thinking that the lessons of 2014, when Ebola claimed 11,000 lives, were learned. In actuality, up until 2014, treating such diseases had usually been the remit of national governments - like the US, Canada, the UK, China or Russia - as the scale of previous outbreaks of infectious diseases was never sufficient to justify billions being invested by profit-driven private pharmaceutical companies.
And Ebola isn’t going to be the health challenge that leads them to change their ways. Writing in The Independent, Oxford University’s Professor Adrian Hill observes that there was never a real business case for the Ebola vaccine “because of the nature of the outbreak…because of the number of people likely to be affected was, until now, thought to be very small and [because] the people affected are in some of the poorest countries in the world and can't afford to pay for a new vaccine." In short, thousands died due to a “market failure”, as the WHO’s outgoing Director Margaret Chan, once said.
This is borne out by the fact that the work to create a vaccine actually started 10 years ago. But the research stalled at the Phase One clinical trial juncture due to a lack of funding. Only when the recent outbreak started did interest in the vaccine resurface.
Western governments need to realise that to completely rely on the for-profit pharmaceutical sector to drive the process to develop vaccines is to accept that only drugs that have a lucrative market will ever be developed. As the Ebola crisis proved, this is disastrous for public health. Governments need to change their approach and understand they need to invest significantly larger sums in prevention and vaccines. The pharma sector won’t change, so they will have to.