By Lina Saigol, Jaimy Lee
AstraZeneca said on Monday that its experimental COVID-19 vaccine had produced an immune response in both older adults, the age group at highest risk from the disease, as well as younger adults, in the Phase 2 study.
The potential vaccine, AZD1222, which is being developed in collaboration with the University of Oxford, triggers protective antibodies and T-cells in older age groups.
“It is encouraging to see immunogenicity responses were similar between older and younger adults and that reactogenicity was lower in older adults, where the COVID-19 disease severity is higher. The results further build the body of evidence for the safety and immunogenicity of AZD1222,” said a spokesperson for the drugmaker.
The interim results further build on preliminary data from the Phase 1 and 2 clinical trials published in July in the medical journal The Lancet . The trial, which involved 1,077 healthy participants aged 18 to 55, showed that the vaccine induced two forms of human immune response generating antibodies and T-cells — for at least 56 days.
Shares in AstraZeneca (LON:UK:AZN) , which is seen as a front-runner in the race to produce a vaccine to protect against COVID-19, rose 1.16% in early London trading on Monday.
However, although the early-stage interim results suggest that the vaccine is safe and that it triggers promising responses, it doesn’t yet prove that it offers long-term immunity or that it has a confirmed safety profile.
Moderna (NAS:MRNA) also recently shared data from a Phase 1 study in the U.S. that indicates the drugmaker’s COVID-19 vaccine candidate generated neutralizing antibodies in older and elderly adults. It had first disclosed similar interim data for its 18-to-55-year-old cohort back in May.
AstraZeneca’s news comes as further restrictions on activity were introduced in Europe on Monday to combat a second wave of COVID-19. World Health Organization Director-General Tedros Adhanom Ghebreyesus said Northern Hemisphere countries are facing a “dangerous moment.”
AstraZeneca voluntarily paused its Phase 3 vaccine study worldwide on Sept. 9, after a volunteer in the U.K. developed an “unexplained illness.”
A week later, trials in the U.K. restarted, followed by trials in Brazil , South Africa, India, and Japan.
When AstraZeneca paused its trials, it said that unexplained illnesses can happen “by chance” in large trials and must be independently reviewed.
An information sheet for participants in the trial from the University of Oxford states that the “unexplained neurological symptoms,” which included changed sensation or limb weakness, were either considered unlikely to be associated with the vaccine or there was “insufficient evidence” to say for certain whether the illnesses “were or were not related to the vaccine.”
On Oct. 23, AstraZeneca’s vaccine trial was given the green light to restart in the U.S., after the regulator concluded it was safe to resume testing the experimental candidate.
The Food and Drug Administration had been investigating whether serious adverse events could be linked to the vaccine.
“The restart of clinical trials across the world is great news as it allows us to continue our efforts to develop this vaccine to help defeat this terrible pandemic,” said Pascal Soriot, AstraZeneca Chief Executive. “We should be reassured by the care taken by independent regulators to protect the public and ensure the vaccine is safe before it is approved for use.”
On Friday, AstraZeneca said its vaccine deal with the University of Oxford will allow it to add up to 20% of manufacturing costs to cover additional expenses required to be incurred by the British drugmaker.
“AstraZeneca has treated the development of the vaccine as a response to a global public health emergency, not as a profit-making opportunity. In addition to the manufacturing costs, the company is incurring costs in excess of $1 billion globally that include clinical development, regulatory, distribution, pharmacovigilance and other expenses,” said a spokesperson for the drugmaker.
“To cover these additional expenses, the company will add an amount equivalent to a maximum of 20% of the manufacturing costs to ensure there is no material impact on its finances this year while continuing efforts to provide the vaccine at no profit during the pandemic,” the spokesperson added.