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Oxford University/AstraZeneca Vaccine Trials expanding into Kenya

  • Teaser: Kenya is now participating in  one of the world's front runner vaccine trials.

 It has already been performing studies in South Africa, Brazil, the USA and the UK but recently had to halt its studies due to 2 cases of transverse myelitis (a neurological condition) in vaccine participants. However, the trial has since re-started somewhat controversially, with the partners saying there was no connection between the cases of transverse myelitis and the vaccine. However, the Food and Drug Administration (FDA) in the USA is still not allowing the trial to recommence in the USA. . According to the article below in a Kenyan newspaper, Kenyan authorities had not been aware of the suspension of the trial even as it was giving its go-ahead.

However, the trial in Kenya is now continuing to be rolled out in Kenya, working under the auspices of the Kenya Medical Research Institute (KEMRI) in Kilifi County. KEMRI is the Kenyan equivalent of the Centers for Disease Control and the Kilifi branch has been partnering with the Wellcome Trust of the UK for many years. Kenya is also participating in another drug trial on the use of Hydroxychloroquine/Chloroquine, which is called COPCOV. This is to explore more the possible use of the drugs to prevent symptoms of Covid19. Previous trials on the use of Hydroxychloroquine, including one done by the WHO as part of its Solidarity Study, were controversially stopped due to the toxic doses of the drug given, which led to the death of some participants and accusations levelled at the WHO, amongst others involved in the trial.

According to the Standard Newspaper in Kenya on September 10th:

The government approved the first Covid-19 vaccine trials to be conducted in the country in September. The approval posted by Pharmacy and Poisons Board on Tuesday allows for the Oxford University-developed vaccine to be tested in Kenya. The trials to be carried out by the Kenya Medical Research Institute (Kemri) will recruit 400 health workers in Kilifi and Mombasa counties.

This makes Kenya the second country in the sub-Saharan Africa after South Africa to conduct clinical trials for a Covid 19 vaccine. South Africa started trials for the same Oxford University vaccine, known as ChAdOx1 nCoV-19, in June.

Last Tuesday global trials of the vaccine were halted because of a serious and unexpected adverse reaction in a participant in the UK.

AstraZeneca, the vaccine co-developers, said the trials had been suspended worldwide to allow the review of safety data by an independent committee.

Locally though, the trials will determine the vaccine’s safety, ability to generate protection and its efficacy against the new virus in adult Kenyans.

“The study will only enroll 400 healthcare workers including doctors, nurses, clinical officers, pharmacists, mortuary attendants, and allied healthcare professionals” says the protocol.

Health workers have been prioritised due to their high risk of occupational exposure to Covid-19, hence their urgent need for protection. The participants who will get one dose of the vaccine will be followed for 12 months.

Justifying the testing of the vaccine in Kenya, the protocol says this is important because vaccine performance from studies in other populations may work differently in Africa.

On Monday, the Cabinet Administrative Secretary for Health Rashid Aman said seven applications for Covid-19 drug studies had so far been received by the poisons board. “Four of them have been approved,” he said during the daily Covid-19 situation update.

Those approved most recently include a study for the experimental use of chloroquine/hydroxychloroquine for the prevention of Covid-19 in healthy adults.

The study called COPCOV will be conducted by KEMRI at four sites in Kilifi, Mombasa, Nairobi and Kisumu, targeting 1,600 health workers. Globally, the study targets 40,000 participants.

While Chloroquine/hydroxychloroquine has been discounted as ineffective against Covid-19, some experts have argued that this is not supported by evidence.

Also expecting approval is a request by Kenyatta University Teaching, Referral and Research Hospital for the experimental use of blood plasma in Covid-19 patients. “The study is at the regulatory approval stage. As soon as it is all systems go, we will let you know,” Dr Marion Kiguoya-Njau, the deputy director of research at KU, told The Standard last week.

“The primary objective of this trial is to look at the safety and efficacy of convalescent plasma therapy in severely infected patients,” says the study protocol, which targets 208 volunteers.

Potential donors will be required to meet the standard criteria for blood donation. However, they must confirm previous infection with SARS-CoV2 and also test negative to show that they have since recovered.

Earlier, the pharmacy board had approved the World Health Organisation- sponsored Solidarity Trial and a second study in which Aga Khan University Hospital, Nairobi, is experimenting with the arthritis drug, tocilizumab, in Covid-19 patients.

During the Covid-19 briefings yesterday, Aman said the ministry was not yet aware of the suspension. He said plans were already underway to start trials of the vaccine, as the necessary approvals had been given.

“This new information has not come to my attention,” he said, as he announced 104 new cases and eight deaths, raising the case load to 35,460 and fatalities to 607.

The clinical trial of the vaccine, in phase three, targets 30,000 individuals in the United Kingdom, and as the CAS noted, more people from difference ethnicity backgrounds, among them Africans, were to be recruited.

Aman said plans to go on with the trials in Kenya were still in place.

Kenya trial using Rabies Vaccine as a control:

In the vaccine trial being started with KEMRI/Wellcome Trust and Oxford University, the first phase is to give 40 volunteers either the vaccine or a control. If that initial safety trial is successful, another 360 participants will be given either the vaccine or the control, in a randomized way. However, the control being used is not a placebo but a rabies vaccine.  Even though it is known that the rabies vaccine won’t give any immunity to Covid19, it is being justified as a benefit to the volunteers who will get protection against rabies. However, this raises questions about whether some of the safety issues that should be monitored are possible side effects from the vaccine and using a rabies vaccine as a control may only confuse this. Rabies vaccine can be unpleasant and in some cases can lead to serious side-effects. Surely it would be better if the control was a pure placebo so that not only the possible efficacy of the vaccine can be assessed but also any potential side effects of the vaccine. This becomes harder if a rabies vaccine is used. This is not the first time that vaccine trials use another type of vaccine as a control, bringing up questions about the design of such trials.

In another article in September in the East African newspaper,

it announced how Kenya will be given access to a vaccine in 2021 if one is ready for use and up to 9.4 million doses of the vaccine will be made available to most essential workers in Kenya.

 Kenya will receive the Covid-19 vaccine in small portions from 2021 until the country has enough to vaccinate the people at “the highest priority” when the vaccine is available, the World Health Organisation (WHO) has announced.

In a report published on its website on Monday this week, the WHO said that each country, including Kenya, will get doses that vaccinate one in every five people, which is equivalent to 9.4 million people. However, in the first stages when the vaccine is expected to be scarce, Kenya will receive doses in little portions until the Ministry of Health has enough to vaccinate three per cent of the population.

In the document, WHO outlined how it would distribute the vaccine to Kenya and all the 156 countries that signed up for Covax, a Covid-19 vaccine allocation plan which is led by WHO, Gavi, the Vaccine Alliance and the Coalition for Epidemic Preparedness and Innovations (Cepi).

Covax was created to ensure the “equitable access and allocation of Covid-19 health products” between the world’s richest countries and those in the developing world.

Health Director-General Patrick Amoth said: “We joined the (Covax) Covid-19 facility under WHO and GAVI to ensure that we are able to access any vaccines that may result from all the current trials.” The report went ahead to specify who the 3 per cent should be.

It would look, therefore, that part of the incentive to get Kenya to join into vaccine and drug trials is the promise that it will receive doses of the vaccine, if one is ready and safe to use next year. The trial in question in Kenya will take 24 months and therefore, unless a vaccine is fast tracked and avoids completing longer term safety and efficacy trials, any vaccine coming to Kenya will be from another vaccine company. However, it is somewhat confusing as this trial is being said to take 24 months and yet there is active talk of a vaccine being given to Kenya in 2021.

Challenge Studies

One development in vaccine studies is to do challenge studies where subjects are deliberately infected with a pathogen after receiving a vaccine. This is done specifically to ascertain the effectiveness of the vaccine in producing antibodies and immunity. A challenge study is now being planned for the Oxford University vaccine trial as well as the one at the Royal Free Hospital in London. Both are being supported by the UK government. Challenge studies have always been controversial ethically given that unless one has a known treatment, infected people with pathogens with potentially unknown effects may be very risky. In this case of Covid19, drug companies are in a hurry to find a vaccine and so the ethical issues of deliberately infecting people with the virus is deemed to be justifiable. This was reported in the UK Telegraph on October 9th. 

The article states the following:

A vaccine is important, because Sir Patrick (Vallance, UK Chief Medical Officer) noted that just "something under 8 per cent of the population" have been infected and/or have antibodies. It may be higher in the cities, as high as 17 per cent, he said, but added that the vast majority of us do not have immunity. Even those who do have antibodies will probably see their immunity diminish over time. 


Challenge studies are highly debatable given the risks involved. This has been well-known for a long time and recently was discussed in the following article:

One potential way to speed up the development of a vaccine for Covid-19 is a “challenge study,” in which researchers give healthy subjects a prospective vaccine and then infect them with the coronavirus. In conventional trials researchers typically give subjects either a test vaccine or a placebo and follow them over time in their ordinary living conditions to see if the vaccine is effective. But there’s no need to wait for a naturally occurring infection in a challenge study, which allows it to be shorter and to require far fewer subjects. Yet such a study would also require deliberately giving those subjects a potentially deadly illness for which there is no good treatment, and for some observers, that’s a deal-breaker. A joint statement by the AIDS Vaccine Advocacy Coalition and the Treatment Action Group says, “Until there is an approved treatment, a challenge trial with a potentially fatal and as-yet untreatable pathogen is unacceptable.”

Nonetheless, the drumbeat for Covid-19 challenge studies is growing louder, and some of the most energetic drummers are bioethicists. Nir Eyal, a bioethicist at Rutgers, was one of the first to call for them. His proposal, cowritten with the epidemiologists Marc Lipsitch of Harvard and Peter Smith of the London School of Hygiene and Tropical Medicine, appeared online in late March. Challenge studies have also been endorsed by the NYU bioethicist Arthur Caplan and the vaccinologist Stanley Plotkin. Julian Savulescu and Dominic Wilkinson, bioethicist-physicians at Oxford, have raised the moral stakes even higher by proposing not just that researchers conduct Covid-19 challenge studies but that the first human subjects could be elderly nursing home patients. “Their motives might be purely altruistic,” Savulescu and Wilkinson wrote. “Or they may be fatalistic or wish to die, or at any rate not care if they die sooner rather than later.”

The utilitarian argument for challenge studies is straightforward: calculate the number of lives risked and compare it to the potential number of lives saved. Backers of challenge studies point to a study (based on data from China) that estimates the risk of death from Covid-19 for a healthy adult between the ages of twenty and twenty-nine at 0.03 percent.

It will have to be seen whether they will want to do a challenge study in Kenya or another African country. This is a controversial issue, given the common (and valid) notion in Africa that drug companies use Africans for drug research. Historically this has been the case and even though challenge studies are now going to be done in the UK and elsewhere, it is distinctly possible that they could be rolled out in African countries as well. Given that the Kenyan government didn’t even know that the AstraZeneca trial had been suspended, it should ensure it is given all the facts before agreeing to do challenge studies for a Covid19 vaccine.

Why is Patrick Vallance, UK Chief Scientific Officer confused about Herd Immunity

One other topic is that of herd immunity. It is often used to justify the need for widespread vaccination but is now being dismissed as a valid approach to deal with the Covid19 situation. A vaccine works by stimulating antibodies to the virus but as Dr Vallance admits in the article above, if its not clear how long natural immunity will last it will not be clear how long immunity from a vaccine will last. Vallance also should perhaps have a better idea of the concepts of herd immunity. He assumes that the majority of people still have no immunity whereas its distinctly possible that a high percentage of people already had some natural immunity from exposure to similar corona viruses in the past and that many have been exposed now and remain without symptoms. His assumption that that most people still don’t’ have any natural immunity does not hold water given that even if we are seeing an increase in positive tests, we are not seeing that many more hospitalizations and mortalities. Again, it seems to be because he sees a vaccine as the only solution.

More and more people are now saying that the only approach that will work is to allow a natural herd immunity to develop amongst healthy population and to protect only the aged and vulnerable. The WHO is coming out against this, saying herd immunity is unethical, but in the classic Orwellian speak of the WHO says at the same time that herd immunity from vaccines is OK, but not the natural disease herd immunity, which is how humans have survived most epidemic diseases in history. They would have a point if Covid19 was killing many millions but it is not. 

A global petition   has been established in order for people from all over the world to sign and to make it clear that the current strategies of governments worldwide to maintain lockdowns of varying degree of intensity and to solely focus on a vaccine as a solution is the wrong approach.