With Pfizer reiterating plans on Wednesday to seek approval for a COVID-19 vaccine — after extensive analysis in Groton of promising studies on efficacy and side effects — Connecticut officials meet Thursday to accelerate planning on how to help hospitals get their hands on the vaccine and keep it stored at the ultra-frozen temperatures necessary to keep it viable.

On Wednesday, Pfizer and BioNTech announced a nearly 95 percent efficacy rate for the COVID-19 candidate vaccine they are co-developing, after additional analysis of an ongoing clinical trial of some 44,000 people globally. Pfizer and BioNTech plan to file for U.S. Food & Drug Administration approval within days, in keeping with the timeline of the third week of November articulated last week by Pfizer CEO Albert Bourla.

BioNTech paired with Pfizer early on in the pandemic to speed the development of a COVID-19 vaccine, based on the German company’s process for delivering instructions to the body on how to build up its defenses.

The vaccine would be administered in twin doses three weeks apart. On Wednesday, Pfizer stated it observed minimal side effects in early clinical trial returns, with less than 4 percent of a subset of trial participants reporting fatigue, and 2 percent headaches.

In late October, two weeks after Connecticut filed its preliminary plan to distribute vaccines, the Centers for Disease Control and Prevention issued what the CDC called an “interim playbook” to govern policy. CDC warned states to be prepared for the administrative challenges of any surge in COVID-19 vaccine demand — but also to be ready to redistribute vaccines to other locales in the event of wider-than-expected reluctance to take vaccines that have generated only months of data in clinical tests to assess safety.

Health-care workers are to get the earliest doses among those having direct contact with patients being treated for COVID-19, followed by a “phase 1B” cohort of workers in other sectors deemed essential; people above age 65; or those with medical conditions making them more susceptible to dangerous complications if contracting the virus. CDC recommends the earliest vaccinations occur in “closed point-of-dispensing settings” in its words that allow for maximum control of exposure to infection, whether at hospitals or temporary off-site locations.

‘Thermal shippers’ for distribution

States will set their own priorities on how vaccines will be distributed to their own populations, with Gov. Ned Lamont’s COVID-19 Vaccine Advisory Group convening Thursday night to review progress and set next steps. As of early Wednesday morning, the group had yet to post publicly its agenda for the meeting under co-chairs Deidre Gifford, acting commissioner of the Connecticut Department of Public Health, and Reginald Eadie, CEO of Trinity Health of New England.

Spokespeople at DPH and in the governor’s office did not respond immediately Wednesday to a request on the advisory group’s immediate plans.

Pfizer is aiming to manufacture doses sufficient for 25 million people this year and as many as 650 million people in 2021, with Lamont stating his expectation last week that Connecticut would receive about one of every 100 doses distributed in the United States.

Pfizer’s sprawling Groton research center has led safety and efficacy studies of the trial, with the company having its main vaccine research arm in Pearl River, N.Y. Pfizer is manufacturing doses in Andover, Mass., St. Louis and Kalamazoo, Mich., with the CDC indicating the company plans to ship directly to vaccination sites.

Doses must be shipped and stored frozen at temperatures approaching 100 degrees below zero. Pfizer and BioNTech have designed reusable “thermal shippers” containing nearly 1,000 doses each, packed with dry ice and sensors to monitor that vials are kept frozen at the required temperatures with hospital staff allowed to crack them open only twice a day.

To administer the Pfizer vaccine, hospitals will be required to certify for the CDC whether they have special-purpose “ultra-low” freezers to store vials. But the CDC has indicated hospitals do not need to add extra units, provided they replenish dry ice in the containers upon arrival and every five days afterward.

It takes 50 pounds of dry ice to “recharge” each container, along with special gloves to protect the skin for anyone handling dry ice. The CDC specifies that 15 days after receipt, doses can be refrigerated at up to 46 degrees if administered within five days.

In a Wednesday news release, Pfizer stated it “is confident in its vast experience, expertise and existing cold-chain infrastructure to distribute the vaccine around the world.”

A Yale New Haven Health official indicated Wednesday the system has ultra-cold storage capacity for at least 100,000 doses, with members including Bridgeport Hospital, Greenwich Hospital and Lawrence + Memorial Hospital in New London.

“Working closely with state and [federal] government officials, we are developing evidenced-based criteria and logistics for the distribution of potential COVID-19 vaccines,” stated Stacy Vaeth, Yale New Haven Hospital’s executive director of pharmacy, in an email response to a query forwarded by a spokesperson.

A spokesperson with Griffin Hospital described the Derby hospital as “fully prepared” to store vaccines including those earmarked for ultra-cold storage.

Cambridge, Mass.-based Moderna announced Monday that its own vaccine candidate was found to have a 94.5 percent efficacy rate in preliminary clinical trial results, with doses stored at normal refrigerator temperatures for up to a month, or frozen for up to six months. If approved by the FDA, the Momenta vaccine would be shipped through McKesson under an agreement with the U.S. Department of Health and Human Services as part of the Trump administration’s “Operation Warp Speed” initiative to fund vaccine development, manufacturing and distribution.

Alex.Soule@scni.com; 203-842-2545; @casoulman