Oxford Covid-19 vaccine faces questions after dosing error

Though the recent back-to-back advancements in the development of a vaccine seemed to have enhanced the visibility of a silver lining in the fight against Covid-19 (SARS-CoV-2) virus, the hope of getting a clinically-approved vaccine remains bleak until the shot receives a go-ahead from the health regulator and the World Health Organisation. 

An error in the Covid-19 vaccine AZD1222, which is being developed by AstraZeneca in association with the University of Oxford, has been under scanner over the slip-up in the doses administered to the participants. The doubts surfaced after the efficiency of Covid-19 shot varied from an efficacy rate of 90 per cent. 

On Monday, the manufacturers said the vaccine can have the efficacy of 90 per cent when first given a half dose and then followed by a full dose a month later. But the manufacturers didn’t disclose that the findings were the result of a mistake. Originally, around 2,741 participants were given a lower dose whereas they shouldn’t have got it in the first place. 

This has raised doubts with scientists and experts questioning the transparency of the trial process. Industry experts and healthcare veterans said that the irregularities reported by AstraZeneca have eroded the confidence in their vaccine development program.

The efficiency fluctuating from 90 per cent to 62 per cent has concluded in an average efficacy level of 70 per cent, AstraZeneca had claimed. The British pharmaceutical major has injected 2,741 participants with a half dose, followed by a full dose a month earlier, while 8,895 volunteers were given two full doses in a gap of a month. 

The vaccine has attained a combined efficacy level of 70 per cent on the basis of two different dosing regimens including a total participant count of 11,636. According to AstraZeneca, the efficacy reading will be refined upon the accumulation of additional data followed by more detailed analysis that can further help in rectifying the duration of protection. 

Matt Hancock, Secretary of State for Health, has been updated about the recent breakthroughs in the Covid-19 vaccine development. The Medicines and Healthcare Products Regulatory Agency (MHRA) has to determine the safety standards of a coronavirus vaccine before giving a go-ahead to the shot selected for billions. The National Health Service (NHS) stands ready for the countrywide rollout of the vaccine with utmost safety upon the successful regulatory approvals, Hancock said.


AstraZeneca Plc (LON: AZN) shares

Shares of AstraZeneca Plc, the Cambridge-headquartered biotech and pharmaceuticals company, have been on a falling trend since the beginning of this week. The stock of AstraZeneca Plc has lost nearly 7 per cent in the last four trading sessions. As per the data available with the London Stock Exchange, AstraZeneca shares have fallen by 6.84 per cent to reach a value of GBX 7,748 on 26 November from GBX 8,317 on 20 November. 

AstraZeneca Plc shares (5-day performance)

(Source: Refinitiv, Thomson Reuters)