UPDATED: AstraZeneca says monoclonal antibody combo is 77% effective at preventing Covid-19
After hitting just about every pothole with its Covid-19 vaccine rollout, AstraZeneca has some good news to share for another pandemic-related program: Its monoclonal antibody combo, AZD7442, proved effective at preventing symptomatic Covid-19 in a Phase III study.
AZD7442 reduced the risk of symptomatic Covid-19 by 77%, based on a preliminary group of cases in a large, global Phase III trial, according to the British pharma. The study, dubbed PROVENT, enrolled nearly 5,200 volunteers across the US, UK, Spain, France and Belgium, 75% of whom had comorbidities or conditions that would cause a reduced immune response to vaccination.
“We intentionally recruited people at high risk or an increased risk for an inadequate response to vaccination, or having a severe SARS-CoV-2 infection,” Mark Esser, VP of microbial sciences and biopharmaceuticals R&D, told reporters in a press conference on Friday morning.
Of 25 reported Covid-19 cases at the preliminary readout, there were no severe cases or deaths in the treatment arm, and three severe cases and two deaths in the placebo arm.
That’s all the efficacy data AstraZeneca is sharing for now, though the company says it’s running the results to regulators in pursuit of an emergency use authorization or conditional approval for the prevention of Covid-19.
“We don’t normally talk about submission timelines. The team is being pushed very hard to try and get a submission in within, you know, I would say a few weeks,” EVP of biopharmaceuticals R&D Mene Pangalos said during the call. “I think it’s not unrealistic to hope that we might get an approval before the end of the year,” he added.
While the readout looks at data collected before the Delta variant gained prominence across the globe, AstraZeneca says it has preliminary in vitro data suggesting the AZD7442 neutralizes emerging variants, including Delta. Adverse events were balanced between the placebo and treatment groups, according to Pangalos.
“There’s nothing that’s standing out in terms of adverse events,” he said.
The pharma is evaluating AZD7442 in a variety of settings. The candidate — discovered by the Vanderbilt University Medical Center and licensed to AstraZeneca last June — is a combination of the antibodies tixagevimab and cilgavimab, derived from B cells donated by recovered Covid-19 patients.
In addition to the PROVENT, AZD7442 is also in the ongoing TACKLE COVID-19 program, which looks at the antibodies’ ability to treat and prevent Covid across more than 9,000 participants in the outpatient setting. And while volunteers got the candidate injected into the muscle in PROVENT, it’s also being assessed as an IV drug.
Back in June, AZD7442 missed the mark in a study assessing its ability to prevent symptoms in adults who had a confirmed exposure to Covid-19. AstraZeneca says the antibody combo performed better in a pre-planned analysis of PCR-negative volunteers.
Prophylactic treatments like AZD7442 could prove useful for those with weaker immune systems, or those who don’t respond well to a vaccine. That includes patients who are on chemotherapy, have blood cancers, or are taking immunosuppressants, among others. And as the rise of concerning variants renders previously authorized treatments ineffective, the US is looking for anything it can get to stave off severe cases.
The federal government struck a deal with AstraZeneca back in March for an extra half-million doses of AZD7442, building on its existing 100,000-dose order from October. The company also has a separate agreement with the Department of Defense for 100,000 doses, bringing its total commitment to the US up to 700,000 doses in 2021.
While no volunteers in PROVENT had been vaccinated before joining the study, AstraZeneca says it sees AZD7442 as a supplement to the currently approved vaccines. While it can be taken alone, the reality is a majority of people will likely use it in addition to a vaccine, Pangalos said. Over the course of the study, more than 400 people in the treatment arm decided to opt out and get vaccinated, and researchers have seen “no issues there,” according to Esser.
“We’ve done preclinical studies in non-human primates or monkeys to show that the antibody doesn’t interfere with vaccination, and we hope to publish that shortly,” he added.
The company declined to comment on how much the treatment might cost, if eventually authorized by regulators.
The news comes a couple months after the US paused the use of Eli Lilly’s antibody combo, urging caregivers to opt for Regeneron’s cocktail as an alternative because it’s more effective against the variants.
AstraZeneca’s celebrating the good news after a rocky vaccine rollout, including a legal battle over shipment delays in the EU and reports of rare blood clots in those who received the vaccine.
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