Around 2,000 people will participate in a trial in South Africa of a Covid-19 vaccine. The operation is led by Wits University in Johannesburg. It receives doses of ChAdox1 nCov-19, a product developed by the University of Oxford. It is only one of dozens of vaccines announced since the start of the coronavirus epidemic, but, it is said, one of the most promising.
Other tests on this vaccine are being carried out or planned in the United Kingdom, Brazil and the United States. First, the tests are used to check that the vaccine is not dangerous for the patients, that it does not develop side effects.
The tests are also used “to measure the response of the immune system”, said a pediatrician from the University of Wits, interviewed by France24. This so-called “phase 2” trial seeks to define the best dose that is suitable for the immune system.
The South African step is expected to last approximately one year. From a few volunteers at the start, it will therefore affect around 2,000 South Africans. The first volunteers are between 18 and 65 years old and do not suffer from any illness requiring special medical supervision. Gradually, the tests will be extended to less healthy populations, in order to check their reaction to the injection.
This trial in South Africa is of great importance. We remember that in April, the awkward remarks of a French researcher, who proposed to test vaccines in Africa, had aroused the disapproval of WHO and those of all Africans. However, it is necessary to test a vaccine on different populations, because the immune responses are not the same in Africa as in Europe or Latin America. Some countries, notably DR Congo, had also expressed interest in vaccine tests.
Regain confidence in tests!
From this point of view, South Africa, with its genetically diverse population, is an obvious choice. Its health environment is also interesting from a scientific point of view: the country has quality infrastructure, but diseases such as tuberculosis or HIV are difficult to combat. It is moreover not impossible that secondly, AIDS patients, therefore immunodeficient, take part in the tests.
Of course, if it is really promising, the vaccine will have to be tested on other populations. If the tests take place without incident, the African populations could regain confidence in the new vaccines, they who had the feeling, not without reason often, of appearing as guinea pigs without finding great benefit.
Note that South Africa is also used as a test for a “double-blind” study on BCG. Does the famous tuberculosis vaccine prevent, not at least the contamination, but at least the serious forms of Covid-19? This is what the researchers are studying from 500 patients who will receive BCG. By definition, this hope – tenuous – will only be confirmed in the medium term, out of the 500 people in question, few will be infected with the coronavirus.
Time is money!
“The virtual absence of Africa on the clinical trial map is a big problem”, the researcher said in a recent note. Which specifies: “The continent displays an incredible genetic diversity. If this diversity is not well represented in clinical trials, the results of the trials cannot be generalized to large populations.”
Given this diversity, studies on the Covid-19 can only be carried out locally. Different populations will respond differently to drugs and vaccines. Also, she believes that “more countries on the African continent must urgently get involved in clinical trials so that the data collected faithfully represent the continent at the genetic level”.
The usual approach of developing site-specific or country-specific protocols will not work. Instead, “African governments must seek ways to harmonize the response to Covid-19 across the continent”, said the scientist. Africa has an infrastructure and capacities for clinical trials. But resources remain unevenly distributed. The vast majority are found in Egypt and South Africa. This is because these countries have invested more heavily in Research & Development than others on the continent.
A research hub?
And the specialist to consider inter-country collaborations such as the pooling of resources between different governments and scientists in the co-design of trials. This involves harmonized guidelines on patient management, sample collection and monitoring and sharing of results in real time.
Due to the unequal distribution of skills and resources, the continent should also adopt a “hub” model in its efforts. This would imply that countries that do not have much capacity are able to easily ship samples across borders for analysis in a well-equipped centralized laboratory, which then returns the data to the country of origin of the sample. Of course, ethics should not be compromised by haste.
Beyond the current pandemic, an African response would make sense: it would encourage governments to assess their role and their level of investment in clinical trials. “This will increase the quality and quantity of clinical trials in the face of the constant challenge of emerging and re-emerging infectious diseases and the constant increase of noncommunicable diseases.”
