Vaccines take time to develop; the first to roll out might not necessarily be the best
The global clamour for a COVID-19 vaccine has whipped up unrealistic expectations that one is just around the corner. It is thus a reality check when biopharma company AstraZeneca, piloting its vaccine candidate, AZD1222 — there were large Phase-3 trials this month — said it was voluntarily putting the multi-national trial on hold. This was after a ‘serious adverse event’ in a volunteer, which a data safety monitoring board will now examine. The company’s move was first reported by an independent medical news site, underlining the critical role that independent scrutiny plays in one of the greatest global crises. Without a specific cure, the vaccine quest has become more than just a search along the pathway that research and pharma companies have traditionally taken. There are demands that probable vaccines be put into a pipeline for accelerated approval to yield political dividends too.
U.S. President Trump has ‘demanded’ that a vaccine be available before voting day in November. India had its moment of vaccine controversy when the ICMR harried trialists to expedite testing of Bharat Biotech’s Covaxin by August 15. Russia, which is to commence its Sputnik V’s Phase-3 testing, has launched a publicity blitz. Just before reports of the trial pause, AstraZeneca and eight companies developing vaccines signed a pledge that they would not approach regulatory authorities, such as the U.S. FDA, until they had safety and efficacy data from a Phase-3 trial. Overall, the road to a vaccine has become an arena for marketing and jingoism. AZD1222 has already been tested in Phase-1 and Phase-2 trials, where the data on its safety and ability to induce a relevant response by the immune system were evaluated and independent peer-review had deemed it fit to be tested in larger populations. A Phase-3 trial is the most daunting one. In the case of a vaccine, there is the additional burden of proof that it cannot sicken the healthy and the odds of adverse reactions greatly increase when a piece of virus is injected into thousands of volunteers. Vaccine trials take years of development precisely because of the chances of unexpected complications and to expect a vaccine, which has cleared accelerated Phase-1/2 trials, to inexorably clear Phase-3, flies in the face of evidence from the history of vaccine development. Developed at Oxford, AZD1222 was evolved on an adenovirus platform not used in a commercially approved vaccine in humans. They have however been used in an experimental Ebola vaccine. India and the world will gain from a vaccine that has been critically and transparently evaluated and not one that crosses a chimerical finish line first.