The United States invests an additional $315 million to help deliver and administer vaccines in low- and middle-income countries, efficacy data for Pfizer-BioNTech's vaccine in children under five may be ready by the end of the year, and more in this week's roundup of Covid-19 news.

• FDA on Wednesday authorized AstraZeneca's Evusheld antibody cocktail for emergency use to prevent symptomatic Covid-19 infection in individuals with moderately to severely compromised immune systems. According to the Wall Street Journal, the treatment, which involves injections of two different monoclonal antibodies, is another preventive option to Covid-19 vaccines, which have been less effective among the immunocompromised. In August, AstraZeneca reported that Evusheld reduced the risk of symptomatic Covid-19 by 77% in a late-stage clinical trial of 5,197 participants, more than 75% of whom had comorbidities that could render vaccines less effective. According to FDA, one dose of the treatment may offer six months of protection. Currently, AstraZeneca said it is testing the antibody treatment against the omicron variant. "[Evusheld] neutralizes all previous SARS-CoV-2 variants to date, and we are working quickly to establish its efficacy against the new omicron variant," said Mene Pangalos, the company's EVP for biopharmaceuticals research and development. (Carbajal, Becker's Hospital Review, 12/8; Strasburg/Walker, Wall Street Journal, 12/8)

• Nearly two-thirds of U.S. states did not follow CDC guidelines to prioritize patients with cancer during initial rollouts of the Covid-19 vaccines, according to research by Rahul Prasad, a radiation oncologist at the Ohio State University Comprehensive Cancer Center, and colleagues. For the study, Prasad and colleagues searched through every state's Covid-19 vaccination webpage for data on vaccination for cancer patients. They found that while 43 states included cancer patients as a priority subpopulation for Covid-19 vaccination, only 8 provided a specific definition for inclusion and just 17 gave these patients the same priority as those ages 65 and older. According to Prasad, CDC's definition of high-risk medical conditions may have been too broad. "I don't think anyone intended to push people to the back of the line," Prasad said. "The [prioritization] efforts were well intentioned." (Susman, MedPage Today, 12/2)

• Pfizer CEO Albert Bourla last week said the company may have data on the efficacy of its Covid-19 vaccine in children under five available by the end of 2021, The Hill reports. "We have a study in children six months to two years and then another cohort of children two to five years," Bourla said. "So [by] end of the year, beginning of next year, when we see the data, we will know more." According to Axios, the emergence of the omicron variant has raised concerns that young children will be more vulnerable to the virus, underscoring the need to get them vaccinated. (Chen, Axios, 12/4; Lonas, The Hill, 12/3)

• FDA last week expanded the emergency use authorization (EUA) for Eli Lilly's antibody treatment for mild to moderate Covid-19 to include all children and newborns. According to The Hill, FDA in February initially authorized the treatment for use in patients ages 12 and older who weighed at least 88 pounds. The decision to expand the EUA to younger populations was based on clinical trial data of body-weight-adjusted doses of the treatment 125 pediatric patients, MedCity News reports. "Now all patients at high risk of severe Covid-19, including children and newborn babies, have an option for treatment and post-exposure prevention," said Patrizia Cavazzoni, director of FDA's Center for Drug Evaluation and Research. "Children under one year of age who are exposed to the virus that causes Covid-19 may be at particularly high risk for severe Covid-19 and this authorization addresses the medical needs of this vulnerable population." (Robbins, New York Times, 12/9; Weixel, The Hill, 12/3; Vinluan, MedCity News, 12/5; Walker, Wall Street Journal, 12/3)

• The United States Agency for International Development (USAID) on Monday announced that it will invest an additional $315 million to help deliver and administer Covid-19 vaccines in low- and middle-income countries, The Hill reports. "The appeal from our partner nations has expanded," said USAID Administrator Samantha Power. "They are not just asking for doses; they are urging us to provide support that will allow them to administer those doses." According to USAID, the new investment will be used to help with logistical concerns, such as cold storage, as well as launch mobile vaccination sites and deploy health care workers. In addition to these funds, the United States will also invest $10 million in vaccine manufacturing in other countries and $75 million to increase oxygen availability in areas undergoing Covid-19 surges. (Sullivan, The Hill, 12/7)

• GlaxoSmithKline (GSK) and Vir Technology on Tuesday said their Covid-19 antibody treatment, sotrovimab, is potentially effective against the omicron variant, confirming the results of earlier laboratory data. Previously, the companies tested the sotrovimab against several of omicron's mutations, and the latest study tested the treatment against omicron's mutated spike protein. According to GSK, the study found that there was a "less than threefold" drop in the treatment's antibody neutralization activity, which was not significant enough to make it ineffective. "These pre-clinical data demonstrate the potential for our monoclonal antibody to be effective against the latest variant, omicron, plus all other variants of concern defined to date by the [World Health Organization], and we look forward to discussing these results with regulatory authorities around the world," said Hal Barron, GSK's chief scientific officer. Currently, the companies are working with public health laboratories to further test the antibody treatment against a whole live virus of the omicron variant, the Wall Street Journal reports. (Roland, Wall Street Journal, 12/7; Sullivan, The Hill, 12/7)