Drugmaker Pfizer said today it was not yet ready to release data from the late-stage trial of the Covid-19 vaccine it is developing with Germany's BioNTech. 

Pfizer said in a presentation that the independent monitor which will determine whether or not the trial has been successful has not conducted any interim efficacy analyses yet. 

Its chief executive Albert Bourla has previously said the company could release data on whether or not the vaccine works as early as this month. 

US President Donald Trump had said a vaccine could be available before the November 3 election, but in recent weeks his administration has emphasised 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. Pfizer and BioNTech launched their 44,000 volunteer phase 3 study of their vaccine 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 become infected with the novel coronavirus. 

Healthcare investor Brad Loncar said it was difficult to draw a positive or negative conclusion from the fact that the trial has not yet had its first interim analysis. 

Dr David Boulware, professor of medicine at University of Minnesota, said the study's participants may be more adherent to social distancing guidelines than the general population. 

"Who the vaccine trials really need are the people who don't wear masks, who are going out to bars, who go to crowded events, who are singing in church choirs - those are the high risk people," he said. 

Boulware said that a data monitoring board could still review the data relatively quickly - perhaps in less than a day - once the trial hits its first interim point.

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. 

The company also said that if the trial is successful, it still expects to file for emergency authorisation of the vaccine candidate from US regulators shortly after it has enough safety data in late November. It expects to have manufacturing data ready to submit to those regulators before then. 

Pfizer today reported quarterly earnings that beat estimates by one cent, helped by lower-than-expected costs. 

Sales fell 4.3% to $12.13 billion in the third quarter due to a sharp drop in revenue from its off-patent pain drug Lyrica, as well as a $500m hit from the Covid-19 pandemic. 

Excluding items, Pfizer earned 72 cents per share, beating analysts estimates of 71 cents per share, according to IBES data from Refinitiv.