US pharma giant Johnson & Johnson says its vaccine gives a high level of protection against the most severe forms of coronavirus, including the South African variant. While its 66 percent efficacy is far from Pfizer and Moderna's 95 percent, it exceeds the 52 percent recognised by the WHO, and health experts say the single-dose jab could be a "game changer".
Johnson & Johnson says its test results are comparable with the impact of the AstraZeneca treatment, which, like all other Covid vaccines currently in use, requires two injections. The J&J vaccine needs only one shot and can be stored and transported at fridge temperatures of 2°C to 8°C, unlike the Pfizer and Moderna treatments which require super-cold storage facilities.
The technology used in the new vaccine is based on the approach successfully used by J&J against Ebola in West Africa. AstraZeneca and the Russian Sputnik use the same principle, which involves injecting a piece of Covid's reproductive code in order to spark an immune reaction in the patient.
Crucially, according to the American company, its vaccine is around 85 percent effective against the most severe forms of Covid infection, and 100 percent effective in preventing hospitalisation and death.
As US President Joe Biden's chief medical adviser Anthony Fauci pointed out at the launch of the J&J product: "The big question for public health is to keep people out of the hospital, keep the number of emergency cases down."
The company has tested its treatment on 44,000 people in the US, South Africa and Brazil.
It is expected to speed up the global immunisation campaign, since only one injection is needed. Health experts across the world say that could be a "game changer".
“The potential to significantly reduce the burden of severe disease, by providing an effective and well-tolerated vaccine with just one immunisation, is a critical component of the global public health response,” according to Paul Stoffels, chief scientific officer of Johnson & Johnson.
“A one-shot vaccine is considered by the World Health Organization to be the best option in pandemic settings, enhancing access, distribution and compliance.
"Eighty-five percent efficacy in preventing severe Covid-19 disease and prevention of Covid-19-related medical interventions will potentially protect hundreds of millions of people from serious and fatal outcomes of Covid-19. It also offers the hope of helping ease the huge burden placed on healthcare systems and communities,” Stoffels concluded.
No serious side-effects
J&J claims that there have been no serious side-effects during the clinical trials. "Some discomfort at the injection site, some people reported feeling very tired, the vast majority reported nothing at all," according to Mathai Mammen, one of the scientific directors of the trials.
The Johnson & Johnson vaccine also appears to be equally effective across all age groups.
The company is to apply this week to the US Federal Food and Drug Administration for emergency approval of its product. An application to the European Medicines Agency is also expected.
The European Union has already ordered 200 million doses.
Production schedules and delivery dates have yet to be finalised.
Bayer joins global vaccine scramble
Meanwhile, German pharmaceutical company Bayer has announced that it will start producing the vaccine developed by CureVac, another German laboratory, from 2022.
Bayer hopes to make 160 million doses available in the course of next year. This will be in addition to the 300 million which CureVac has promised to produce at its own facilities.
The CureVac treatment is still in the third and final stage of clinical trials, and has not been approved for use anywhere in the world.