A handful of candidate vaccines against Covid-19 have reported efficacy levels of greater than 90 per cent in clinical trials, and Aylward noted that multiple vaccine platforms have shown strong results.
“If you look week by week at the number of companies that are announcing positive results in terms of the efficacy of vaccines, that number is increasing and what’s important is it’s increasing not just in terms of the number of products, but also the different technology platforms that they are being built on. As we’ve seen now, there are three different sorts of technology platforms, as we call them, that have reported very positive efficacy and safety data,” the WHO senior adviser told a media briefing.
Over the past week, US media outlets reported that Pfizer is unlikely to meet its original supply targets for its vaccine against Covid-19, which is produced in conjunction with German firm BioNTech, due to supply chain issues.
GlaxoSmithKline and Sanofi also announced earlier on Friday that their candidate vaccine will likely not be available until the end of 2021 due to disappointing trial results, and Aylward noted the WHO’s concern over the actual number of available vaccine doses.
“But at the same time … there are real challenges with volumes. These are still very, very scarce products. And just as some companies are announcing successes, there are others – and we’ve had two over the last few days – that have said they have had challenges with their products either in terms of the volumes they can produce or in terms of some of the trial results,” the WHO senior adviser said.
At the same media briefing, WHO Director-General Tedros Adhanom Ghebreyesus expressed his belief that more countries will begin their mass coronavirus disease vaccination programs in the near future.