In the wake of news yesterday that AstraZeneca had paused its phase 3 COVID-19 vaccine trial due to a serious safety issue, analysts across the biopharma landscape set out to answer questions and lay out possible scenarios about how the race could play out from here.
Amid its effort to enroll tens of thousands of participants, AstraZeneca voluntarily paused the trial after a patient's adverse event, Stat reported Tuesday afternoon. The New York Times reports a trial participant in the U.K. was diagnosed with transverse myelitis, inflammation of the spinal cord that can be triggered by infections.
The development could result in four possible scenarios, SVB Leerink's Andrew Berens wrote to clients early Wednesday. If the event is determined to not be transverse myelitis or not linked to the AstraZeneca vaccine, the program could proceed after a delay of weeks to months, he wrote.
But if transverse myelitis is confirmed as a reaction to the vaccine, the program would be “terminated,” Berens wrote. And under two other scenarios linking transverse myelitis to the SARS-CoV-2 virus or COVID-19 infection, other vaccine players would naturally be affected.
Still, under any scenario, “the overall pace of many of the programs could be impacted as the investigation progresses and the sponsors become more vigilant,” the analyst wrote.
But in an indication AstraZeneca may have the issue under control, the Financial Times reported on Wednesday the trial could resume next week, citing people familiar with the matter.
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Meanwhile, SVB Leerink’s Mani Foroohar, who on Tuesday downgraded AZ rival Moderna due to competitive pressures, said the mRNA biotech’s share price should react favorably to the news. His team sees “limited readacross” between vaccine platforms from the pause.
Moderna could now be in a position to arrive second to market behind Pfizer, he wrote. Still, Foroohar stood by his underperform rating for the biotech thanks to fierce competition in the overall COVID-19 vaccine field.
For now, the issue is part of a “short- to medium-term debate,” Jefferies analyst Michael Yee wrote to clients on Tuesday.
“We generally believe and have said before that the vaccines, including [Moderna’s], will likely have various differences in efficacy and safety/tolerability and these may drive various opinions about which are best for people,” he wrote.
SVB Leerink analyst Geoffrey Porges said the issue isn't cause for panic, but his team is watching it seriously. A rare safety red flag in a large efficacy trial was one of many reasons his team never counted on COVID-19 vaccines for herd immunity until 2023, he wrote. It could take months for to AstraZeneca to prove the problem wasn't associated with vaccination. Another serious issue could derail the program altogether, Porges wrote.
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As a result of the development, other vaccine makers using adenovirus platforms, such as Johnson & Johnson and CanSino, could face slight delays as they tweak their consent forms and patient brochures, Porges wrote.
And for developers using other vaccine platforms, there's “very little direct spillover," he noted. But the analyst does expect “more careful scrutiny” for vaccines using novel platforms, such as the mRNA programs from Pfizer and Moderna. Companies using traditional technologies such as GlaxoSmithKline, Sanofi and Novavax are in the best position, he added.
All things considered, Porges’ team expects a “politically influenced” emergency use authorization for high-risk populations by the end of the year. Pfizer and Moderna are pressing ahead with mRNA vaccines in late-stage testing, but that technology has never yielded an approved product.
For a wider approval and widespread use, Porges’ team is expecting to wait until mid- to late 2021.