Drugmaker Pfizer Inc said on Tuesday it was not yet ready to release data from the late-stage trial of the COVID-19 vaccine candidate it is developing with Germany's BioNTech SE.
Pfizer's CEO Albert Bourla has said the company could release data on whether or not the vaccine works as early as this month, but the company said in a presentation that the independent data monitoring board which will determine whether or not the trial has been successful has not conducted any interim efficacy analyses yet.
Shares were flat at $37.93 before the opening bell.
US President Donald Trump had said a vaccine could be available before the November 3 election, but in recent weeks his administration has emphasized that one will be ready this year.
Pfizer hopes to be the first US drugmaker to unveil successful data from a late-stage COVID-19 vaccine trial, ahead of rival Moderna Inc. Pfizer and BioNTech launched their 44,000 volunteer phase 3 study of their vaccine candidate in late July.
The data monitoring board is scheduled to make its first assessment of the vaccine's performance after 32 participants in the trial became infected with the novel coronavirus.
As the pandemic crimps demand for certain Pfizer therapies and damages global economies, investors are keenly focused on seeing the late-stage study data of the vaccine candidate being developed with BioNTech.
Pfizer reported quarterly earnings that beat estimates by one cent, helped by better-than-expected sales of its cancer drug Ibrance.
Overall sales fell 4.3 per cent in the third quarter, hurt by a plunge in sales of its off-patent pain drug Lyrica and a $500 million hit to sales from the COVID-19 pandemic.
Sales of cancer drug Ibrance grew 6 per cent to $1.36 billion, beating analyst estimates of $1.39 billion, despite increased competition from Eli Lilly's Verzenio.
Excluding items, Pfizer earned 72 cents per share, beating analysts estimates of 71 cents per share, according to IBES data from Refinitiv.