Nasal COVID vaccine blows clinical trial, sending researchers back to lab
Nasal COVID vaccine blows clinical trial, sending researchers back to lab
Enlarge / A man receives an H1N1 nasal flu vaccine at an urgent care center emergency on October 16, 2009, in Lake Worth, Florida.
Getty | Joe Raedle
The nasal version of the Oxford/AstraZeneca COVID-19 vaccine failed an early-stage clinical trial, dashing hopes of better infection prevention and forcing researchers to rethink the design.
Many experts have highlighted the potential of nasal vaccines against COVID-19. They argue that snorting the injections could coat the nasal mucous membranes with snotty antibodies, namely IgA, and other immune defenses that could eliminate SARS-CoV-2 virus particles before they have a chance to cause an infection. Currently, injections given intramuscularly in the arms provide robust systemic immune responses that prevent serious illness and death, but stimulate relatively low antibody levels on the mucous membranes and therefore do not always prevent the infections.
Researchers at the University of Oxford hoped to easily adapt their existing COVID-19 vaccine for such an infectious schnoz spritz. The Oxford/AstraZeneca vaccine is a viral vector-based design, using a weakened benign virus to carry the genetic code for the SARS-CoV-2 spike protein into human cells. The mild virus in this case is an adenovirus, a type best known for causing mild cold-like illnesses in humans, although the specific virus used in the vaccine was isolated from chimpanzees. (This vaccine has not been licensed in the United States but is used in dozens of countries around the world.)
Researchers had a whiff of success in preclinical trials involving non-human primates, which developed strong mucosal antibody responses after nasal administration. But their hopes were dashed in the first clinical trial, the results of which were published this week in the journal eBioMedicine.
Disappointing data
In the 42-person Phase I trial, nasal administration of the vaccine elicited modest mucosal antibody responses in only a few participants and also stimulated weaker systemic responses than intramuscular injections. The trial included 30 people who had not been previously vaccinated and 12 vaccinated people who tested the nasal vaccine as a booster. Nasal administration blew it on both counts. The only good news is that no security issues were detected.
But, in even more disappointing results, the vaccine was also found to be ineffective in preventing COVID-19. The small, early-stage trial was not designed to assess efficacy, but researchers note that 7 of 42 participants reported SARS-CoV-2 infections after nasal vaccination. This is "dispiriting for the prospect of robust and long-lasting protection," the Oxford researchers concluded in the published study.
In a press release, the trial's lead researcher, Sandy Douglas, of the Jenner Institute at the University of Oxford, put it mildly, saying, "The nasal spray didn't perform as well in this study than we had hoped."< /p>
Douglas noted that data from researchers in China suggests more success with a similar vaccine administered with a nebulizer device, although the Oxford researchers noted that they wanted to aim for the more convenient administration of a nebulizer. nasal spray. Douglas also noted that an intranasal vaccine has been approved in India, but clinical trial data on this vaccine has yet to be released.
Overall, Douglas suggested that his research team return to the design stage, such as coming up with new formulations that could help the vaccine slip better onto the nostrils and airways to avoid slip into the stomach. The researchers also wondered if the adenovirus vector, originally wiped clean from chimpanzees, might just be bad at infecting human snouts. They also considered trying larger doses.
Although the results of the trial are a setback for the cause, outside experts have urged the researchers not to give up. The result is "disappointing", infectious disease expert Andrew Freedman of Cardiff University said in a statement. "That shouldn't be a further deterrent though...
Enlarge / A man receives an H1N1 nasal flu vaccine at an urgent care center emergency on October 16, 2009, in Lake Worth, Florida.
Getty | Joe Raedle
The nasal version of the Oxford/AstraZeneca COVID-19 vaccine failed an early-stage clinical trial, dashing hopes of better infection prevention and forcing researchers to rethink the design.
Many experts have highlighted the potential of nasal vaccines against COVID-19. They argue that snorting the injections could coat the nasal mucous membranes with snotty antibodies, namely IgA, and other immune defenses that could eliminate SARS-CoV-2 virus particles before they have a chance to cause an infection. Currently, injections given intramuscularly in the arms provide robust systemic immune responses that prevent serious illness and death, but stimulate relatively low antibody levels on the mucous membranes and therefore do not always prevent the infections.
Researchers at the University of Oxford hoped to easily adapt their existing COVID-19 vaccine for such an infectious schnoz spritz. The Oxford/AstraZeneca vaccine is a viral vector-based design, using a weakened benign virus to carry the genetic code for the SARS-CoV-2 spike protein into human cells. The mild virus in this case is an adenovirus, a type best known for causing mild cold-like illnesses in humans, although the specific virus used in the vaccine was isolated from chimpanzees. (This vaccine has not been licensed in the United States but is used in dozens of countries around the world.)
Researchers had a whiff of success in preclinical trials involving non-human primates, which developed strong mucosal antibody responses after nasal administration. But their hopes were dashed in the first clinical trial, the results of which were published this week in the journal eBioMedicine.
Disappointing data
In the 42-person Phase I trial, nasal administration of the vaccine elicited modest mucosal antibody responses in only a few participants and also stimulated weaker systemic responses than intramuscular injections. The trial included 30 people who had not been previously vaccinated and 12 vaccinated people who tested the nasal vaccine as a booster. Nasal administration blew it on both counts. The only good news is that no security issues were detected.
But, in even more disappointing results, the vaccine was also found to be ineffective in preventing COVID-19. The small, early-stage trial was not designed to assess efficacy, but researchers note that 7 of 42 participants reported SARS-CoV-2 infections after nasal vaccination. This is "dispiriting for the prospect of robust and long-lasting protection," the Oxford researchers concluded in the published study.
In a press release, the trial's lead researcher, Sandy Douglas, of the Jenner Institute at the University of Oxford, put it mildly, saying, "The nasal spray didn't perform as well in this study than we had hoped."< /p>
Douglas noted that data from researchers in China suggests more success with a similar vaccine administered with a nebulizer device, although the Oxford researchers noted that they wanted to aim for the more convenient administration of a nebulizer. nasal spray. Douglas also noted that an intranasal vaccine has been approved in India, but clinical trial data on this vaccine has yet to be released.
Overall, Douglas suggested that his research team return to the design stage, such as coming up with new formulations that could help the vaccine slip better onto the nostrils and airways to avoid slip into the stomach. The researchers also wondered if the adenovirus vector, originally wiped clean from chimpanzees, might just be bad at infecting human snouts. They also considered trying larger doses.
Although the results of the trial are a setback for the cause, outside experts have urged the researchers not to give up. The result is "disappointing", infectious disease expert Andrew Freedman of Cardiff University said in a statement. "That shouldn't be a further deterrent though...
Enlarge / A man receives an H1N1 nasal flu vaccine at an urgent care center emergency on October 16, 2009, in Lake Worth, Florida.
Getty | Joe Raedle
