AstraZeneca said on Thursday that new data from the AZD7442 Covid-19 ‘PROVENT’ prevention and ‘TACKLE’ outpatient treatment phase 3 trials both showed “robust efficacy” from a one-time intramuscular dose of the long-acting antibody combination.
The FTSE 100 pharmaceuticals giant said that in an analysis of the ongoing PROVENT trial, evaluating a median six months of participant follow-up, one 300mg intramuscular dose of AZD7442 reduced the risk of developing symptomatic Covid-19 compared to placebo by 83%.
It said around 2% of the global population was considered to be at an increased risk of an “inadequate response” to a Covid-19 vaccine.
That includes people with blood cancers or other cancers being treated with chemotherapy, patients on dialysis, those taking medications after an organ transplant, or who are taking immunosuppressive drugs for conditions including multiple sclerosis and rheumatoid arthritis.
The AZD7442 PROVENT trial was the first phase 3 trial prospectively designed to evaluate a monoclonal antibody for pre-exposure prophylaxis of symptomatic Covid-19, with targeted inclusion of high-risk and immunocompromised participants.
More than 75% of PROVENT participants at baseline had comorbidities that put them at high risk for severe Covid-19 if they were to become infected, including people who were immunocompromised, and may have a reduced immune response to vaccination.
There were no cases of severe Covid-19 or Covid-19-related deaths in those treated with AZD7442 at either the primary or six-month analyses.
In the placebo arm, there were two additional cases of severe Covid-19 at the six-month assessment, for a total of five cases of severe Covid-19 and two Covid-related deaths.
AstraZeneca said an exploratory analysis of the TACKLE outpatient treatment trial in patients with mild-to-moderate Covid-19, meanwhile, showed that one 600mg intramuscular dose of AZD7442 reduced the risk of developing severe Covid-19 or death from any cause by 88% compared to placebo, in patients who had been symptomatic for three days or less at the time of treatment.
A total of 90% of participants enrolled in TACKLE were from populations at high risk of progression to severe Covid-19 if they became infected, including those with comorbidities.
In both PROVENT and TACKLE, AZD7442 was said to have been generally well-tolerated, with no new safety issues identified in the six-month analysis of PROVENT.
“AZD7442 is the only long-acting antibody with phase 3 data to demonstrate benefit in both pre-exposure prophylaxis and treatment of Covid-19 with one dose,” said AstraZeneca’s executive vice-president of biopharmaceuticals research and development.
“These new data add to the growing body of evidence supporting AZD7442’s potential to make a significant difference in the prevention and treatment of Covid-19.
“We are progressing regulatory filings around the world and look forward to providing an important new option against SARS-CoV-2 as quickly as possible.”
Full results from PROVENT and TACKLE would be submitted for publication in a peer-reviewed medical journal, and presented at a forthcoming medical meeting, the company said.
On 5 October, AstraZeneca announced that it had submitted a request to the US Food and Drug Administration (FDA) for emergency use authorisation for AZD7442, for the prophylaxis of Covid-19.
AstraZeneca said it had agreed to supply the United States federal government with 700,000 doses of AZD7442 if granted such authorization, alongside agreements to supply other countries.
At 1133 GMT, shares in AstraZeneca were down 1.18% at 8,489p.
