The U.S. has moved one step closer to getting its first COVID-19 vaccine, with BioNTech (BNTX) — Pfizer’s (PFE) development partner — filing for emergency use authorization Friday morning.

“Filing in the U.S. represents a critical milestone in our journey to deliver a COVID-19 vaccine to the world and we now have a more complete picture of both the efficacy and safety profile of our vaccine, giving us confidence in its potential,” said Pfizer CEO Albert Bourla.

With the coronavirus crisis reaching a crescendo worldwide, steps toward approving and distributing a COVID-19 inoculation have taken on increasing urgency.

BioNTech’s move comes just days after the two companies announced their two-dose vaccine is 95% effective against the coronavirus, and that they planned to file for regulatory approval “within days.”

While data supporting the statement has yet to be released, health officials are cautiously optimistic. Dr. Anthony Fauci, director of the National Institute of Allergy and Infectious Diseases, said a vaccine’s efficacy is one thing — but the effectiveness in the real world is another.

“If you like at highly efficacious vaccines through the years, they’ve crushed formidable outbreaks like smallpox, like polio, like measles,” Fauci said — calling the 95% threshold “extraordinary.”

Yet concerns still exist over the ease of distributing the BioNTech/Pfizer vaccine, as well as other candidates that could also soon be authorized, to reach the far corners of the country.

President-elect Joe Biden noted that the decision by Operation Warp Speed — the Trump administration’s initiative to fund and produce domestic vaccine candidates — to partner with Walgreens (WBA) and CVS (CVS) was not ideal to reach rural residents, and some communities of color.

“So we have to make sure there is access for them,” Biden said during a press briefing Thursday.

Rural access to a vaccine — and the significantly lower volume demands that could affect prioritization— is a concern expressed by Amerisource Bergen’s Good Neighbor Pharmacy president. Meanwhile, Walgreens has noted on its website that its pharmacies are within several minutes of 80% of the country’s population.

But Warp Speed officials said Wednesday there are already plans to help support areas that need an ultra-cold freezer or other support. On Thursday, Gen. Gustave Perna said there are already 100 million vaccine kits ready to ship, along with the vaccines, 24 hours after an emergency use authorization is granted.

Brandon Daniels, president of global markets at consulting firm Exiger, said now that the vaccine’s efficacy is known, the supply chain’s efficacy is being put to the test.

“Now, we’re seeing cryogenics companies and packaging companies starting to become more significant names in the supply chain,” Daniels said.

It’s possible that the mass coronavirus testing infrastructure, created to help reach hard-to-reach communities, could play a key in vaccine distribution as well, he added.

Meanwhile, states are already preparing to receive the first shipment of vaccines in mid-December, with the expectation that frontline health care workers and nursing homes will be at the top of the priority list.

WHO rejects remdesivir

A panel of World Health Organization doctors said they do not recommend Gilead Science’s (GILD) antiviral remdesivir, marketed as Veklury, to treat Covid-19, in an article in the British Medical Journal (BMJ) late Thursday.

Based on the recent results of trials the WHO conducted on Veklury and other proposed coronavirus treatment options, doctors say there was not enough to support use.

The article “contains a weak or conditional recommendation against the use of remdesivir in hospitalized patients with Covid-19,” the doctors said.

Gilead said in a response that it was disappointed by the decision, considering the U.S. and other countries like Germany, Japan and the U.K. have approved the drug for use in hospitalized patients.

The countries that have approved it did so “based on the robust evidence from multiple randomized, controlled studies published in peer-reviewed journals that demonstrate the clinical benefits of Veklury, such as significantly faster recovery, which can free up limited hospital resources,” Gilead said.

In early October, SVB Leerink analyst Geoffery Porges said that based on all trial results, “remdesivir looks much as it looked in its earlier trials and interim disclosure – moderately effective in patients in the sweet spot for treatment.”

While it was “emphatically not a miracle drug,” Porges noted that it is likely to be used in combination with monoclonal antibodies “in those countries and institutions that can afford the cost and can make the complicated diagnostic decisions about who to treat.”

With a more-than-$3,000 price tag, both remdesivir and monoclonal antibodies are expensive treatment options, compared with the more cost-effective, clinically-effective corticosteroids like dexamethasone that are widely used in treating Covid-19 patients.

“Especially given the costs and resource implications associated with remdesivir, but consistent with the approach that should be taken with any new drug, the panel felt the responsibility should be on demonstrating evidence of efficacy, which is not established by the currently available data,” WHO doctors said.

In a separate move, the U.S. Food and Drug Administration authorized Eli Lilly’s rheumatoid arthritis treatment in combination with remdeisvir for emergency use.

Patrizia Cavazzoni, acting director of the FDA’s Center for Drug Evaluation and Research, said the authorization comes as the need for more treatment options rises.

“Despite advances in the management of COVID-19 infection since the onset of the pandemic, we need more therapies to accelerate recovery, and additional clinical research will be essential to identifying therapies that slow disease progression and lower mortality in the sicker patients,” Cavazzoni said.

More from Anjalee:

• Fauci: Vaccines will only prevent symptoms, not block the virus

• A Biden win could lead to a mask mandate, more testing: Expert

• Trump admin rules for health insurer price transparency has potential to curb costs

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