AstraZeneca (AZN.L) has reported mixed results from trials of a new COVID-19 treatment that it hoped could supplement vaccines.
The pharma giant said trials of its AZD7442 long-acting antibody (LAAB) combination failed to meet the main goal of stopping people developing symptomatic COVID-19 but did offer some hope that it could help people who had not yet come into contact with the virus.
Shares in AstraZeneca ticked up half a percent on Tuesday.
Unlike vaccines based on strains of the virus, AZD7442 is based on antibodies generated by the body to fight off COVID-19. AstraZeneca had hoped the treatment could be used to boost people's immune systems after they'd caught COVID-19. When trials were announced last October, the company said it hoped AZD7442 could be used to supplement vaccines in vulnerable populations or as an alternative where vaccines weren't possible.
AstraZeneca said on Tuesday that its so-called 'Storm Chaser' trials showed AZD7442 was ineffective when it came to boosting immune systems of people who were already infected. But the trials did show strong efficacy when it came to people who were unvaccinated but hadn't come into contact with COVID.
"While this trial did not meet the primary endpoint against symptomatic illness, we are encouraged by the protection seen in the PCR negative participants following treatment with AZD7442," said Mene Pangalos, AstraZeneca's executive vice president of BioPharmaceuticals R&D.
A trial of over 1,200 people found that AZD7442 reduced the chance of developing symptomatic COVID-19 by 33%, which AstraZeneca said was not statistically significant.
However, a deeper analysis showed that the treatment was far more effective when it came to boosting resistance for people who had not yet come into contact with COVID-19. Trial participants who had a negative PCR test at the start of the experiment had a much lower chance of developing symptomatic COVID-19 after receiving the treatment. PCR negative participants had a 92% less chance of developing symptomatic COVID-19 seven days after receiving AZD7442.
"The results of Storm Chaser suggest that AZD7442 may be useful in preventing symptomatic COVID-19 in individuals not already infected," said Dr Myron J. Levin, a Professor of Pediatrics and Medicine at the University of Colorado School of Medicine and the principal investigator on the trial. "The PROVENT trial will give us more clarity in this patient population.
"While COVID-19 vaccination efforts have been successful, there is still a significant need for prevention and treatment options for certain populations, including those unable to be vaccinated or those who may have an inadequate response to vaccination."
AZD7442 has been developed in partnership with the the US government, which has invested around $500m in accelerating its development. In March, AstraZeneca announced a $205m deal to supply the US with up to 500,000 extra doses of the treatment. The UK has also pre-ordered 1m doses but is said to be reconsidering the deal.
Separately, Novavax (NVAX) announced on Monday that its COVID-19 vaccine had proved 90% effective in trails. The UK has ordered 60 million doses of the jab.
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