U.S. pharmaceutical giant Pfizer and its German partner BioNTech said they have submitted an application for conditional approval of their COVID-19 vaccine with the European Medicines Agency.

The submission, which occurred Monday, completes the rolling review process that the two companies initiated with the regulator on Oct. 6.

"Today’s announcement marks another key milestone in our efforts to fulfill our promise to do everything we can to address this dire crisis given the critical public health need," Pfizer chairman and CEO Albert Bourla said in a statement Tuesday. "We have known since the beginning of this journey that patients are waiting, and we stand ready to ship COVID-19 vaccine doses as soon as potential authorizations will allow us."

If the vaccine candidate, called BNT162b2, is approved, the companies said it could potentially be available for use in Europe before the end of the year.

"As a company located in the heart of Europe, today’s milestone is important to us as we continue to seek to enable a worldwide supply upon potential approval of BNT162b2," BioNTech CEO and co-founder Ugur Sahin said in a statement Tuesday. "We will continue to work with regulatory agencies around the world to enable the rapid distribution, should the vaccine receive the approval, contributing to the joint efforts to let the world heal and regain its normal pace of life."

There were 157,901 new cases of COVID-19 confirmed in the United States on Monday, according to a real-time count kept by Johns Hopkins University.

It's the 28th straight day that the country has reported over 100,000 newly diagnosed infections. Monday's count is down from a peak of 205,557 new cases last Friday.

An additional 1,172 fatalities from COVID-19 were also registered nationwide on Monday, less than the all-time high of 2,609 new deaths on April 15.

COVID-19 data may be skewed in the coming days and weeks due to possible lags in reporting over Thanksgiving followed by a potentially very large backlog from the holiday.

A total of 13,545,017 people in the United States have been diagnosed with COVID-19 since the pandemic began, and at least 268,087 of them have died, according to Johns Hopkins. The cases include people from all 50 U.S. states, Washington, D.C. and other U.S. territories as well as repatriated citizens.

Much of the country was under lockdown by the end of March as the first wave of pandemic hit. By May 20, all U.S. states had begun lifting stay-at-home orders and other restrictions put in place to curb the spread of the novel coronavirus. The day-to-day increase in the country's cases then hovered around 20,000 for a couple of weeks before shooting back up over the summer.

The numbers lingered around 40,000 to 50,000 from mid-August through early October before surging again to record levels, crossing 100,000 for the first time on Nov. 4 and reaching 200,000 for the first time on Nov. 27.

The United States saw another record day of COVID-19 hospitalizations, according to the COVID Tracking Project, a volunteer-run effort to track the U.S. outbreak.

The group said the country currently has 96,039 people hospitalized with the disease, with a seven-day average of 91,331.

"Hospitalizations have doubled since November 1 and tripled since October 1. We should see 100k hospitalizations in the next couple of days," The COVID Tracking Project wrote on its Twitter account Monday night.

The group called November the "worst month of the pandemic outside of April," as the nation recorded a record 4.28 million new cases of COVID-19, over 72,000 new hospitalizations and 36,256 new deaths.

President Donald Trump’s coronavirus adviser Dr. Scott Atlas resigned on Monday.

Atlas, a neuroradiologist with no background in infectious diseases who had supplanted Dr. Anthony Fauci and other top federal public health officials as one of Trump's top medical advisers, was reaching the end of his 130-day term as a “special government employee,” according to the official.

Fox News, where Atlas first caught Trump’s eye before the president appointed him to a paid advisory role in the White House, initially reported the news.

Atlas spoke with the president Monday, a White House official confirmed to ABC News.

Atlas did not respond to a request for comment.

-ABC News' Ben Gittleson