U.S. health officials stop shipments of the monoclonal antibody sotrovimab to certain states, Novavax's protein-based vaccine is being tested as a booster in two new clinical trials, and more in this week's roundup of Covid-19 news.

• The World Health Organization (WHO) announced that it is examining rare reports of hearing loss and other auditory issues after Covid-19 vaccination. According to the Uppsala Monitoring Centre in Sweden, 367 cases of tinnitus and 164 cases of hearing loss after Covid-19 vaccination have been reported worldwide as of Feb. 22, 2021. Meanwhile, 14,851 cases of tinnitus have been reported to CDC's Vaccine Adverse Events Reporting System as of March 18. "Tinnitus is a common condition, heterogenous in nature, and has many causes and risk factors," a CDC spokesperson said. " ... Currently, the data from safety monitoring [is] not sufficient to conclude that a causal relationship exists between vaccination and tinnitus." However, WHO noted the possible link between auditory issues and Covid-19 vaccination warrants attention from both physicians and patients. "Awareness of this possible link may help healthcare professionals and those vaccinated to monitor symptoms and seek care as appropriate," WHO said. "As there is still only limited data in the literature providing evidence for this link, further monitoring is required." (Carbajal, Becker's Hospital Review, 3/29; Edwards, NBC News, 3/28; Henderson, MedPage Today, 3/9)

• Case investigation and contract tracing (CICT) programs may have prevented over a million Covid-19 cases and tens of thousands of hospitalizations during the first winter of the pandemic, according to a new CDC modeling study. For the study, researchers analyzed data from 59 CICT programs across 22 U.S. states and one territory collected between Nov. 25, 2020, and Jan. 23, 2021. In a high-impact scenario in which 80% of all interviewed Covid-19 survivors, as well as 30% of notified contacts, followed quarantine guidelines, the researchers estimated CICT programs prevented 1.11 million infections and 27,231 hospitalizations. Similarly, in a low-impact scenario where all Covid-19 survivors and monitored contacts followed quarantine guidelines, the researchers estimated CICT programs prevented 1.36 million infections and 33,527 hospitalizations. In particular, CICT programs in the Midwest prevented the most infections, while those in the West prevented the fewest. Across all scenarios and jurisdictions, CICT programs prevented an estimated median of 21.2% of infections that were not averted by vaccination or other nonpharmaceutical interventions. According to the study's authors, these findings suggest that CICT programs helped contain viral transmission during the study period. "Differences in outcomes across jurisdictions indicate an opportunity to further improve CICT effectiveness," the authors wrote. "These estimates demonstrate the potential benefits from sustaining and improving these programs." (CIDRAP News, 3/28)

   

• Novavax last week announced that its protein-based Covid-19 vaccine, which is currently under review by FDA for use in adults, is involved in two clinical trials to test its viability as a booster shot. One trial is a Phase 1/2 study of 1,130 adult participants being conducted by NIH's National Institute of Allergy and Infectious Disease. In the study, around 180 participants will receive the Novavax vaccine as a third dose while the remainder will receive one of three vaccines already authorized by FDA. Currently, the study is enrolling volunteers at 10 research sites and expects to report initial findings later this year, with full results in 2023. The second trial is a Phase 3 study in the United Arab Emirates. In this study, researchers will test Novavax's vaccine as a booster for participants who were previously vaccinated with Sinopharm, a Covid-19 vaccine developed by the China National Pharmaceutical Group. The trial aims to enroll around 1,000 adult participants at two sites in Abu Dhabi, and results are expected in the fourth quarter of the year. "Additional Covid-19 booster studies are important to support vaccine choice for individuals, health care providers and public health authorities," said Filip Dubovsky, Novavax's CMO. (Gilgore, Washington Business Journal, 3/25)

   

• U.S. health officials last week stopped shipments of Vir Biotechnology and GlaxoSmithKline's monoclonal antibody sotrovimab to certain U.S. states and territories, including New York, New Jersey, Puerto Rico, and the Virgin Islands, where the omicron subvariant BA.2 is dominant. According to laboratory studies, sotrovimab is unlikely to be effective against the subvariant, although it maintained its effectiveness against the original omicron variant BA.1. According to STAT News, this is not the first time the use of an antibody treatment has been limited after losing potency against a new variant. Previously, the federal government halted shipments of antibody therapies made by Eli Lilly and Regeneron after data showed they were no longer effective against the original omicron variant. (Joseph, STAT News, 3/25)

   

• CDC last week announced plans to publish preliminary Covid-19 vaccination data for staff at acute care hospitals in a dashboard "in the near future," although an exact date has yet to be determined. According to Becker's Hospital Review, the dashboard will contain data on both primary vaccination and booster doses among workers at CMS-certified acute care hospitals, including licensed independent practitioners, adult students/trainees and volunteers, and other contract workers, and be updated on a weekly basis. Under a CMS rule, acute care hospitals are required to report quarterly staff vaccination data to CDC, and this first submission, covering Oct. 1 to Dec. 31, 2021, is due on May 16. The deadline for reporting data covering January to March 2022 is August 2022. Instead of releasing quarterly data on hospital vaccination rates, CMS said it plans to release a full year of the data in October. (Gooch, Becker's Hospital Review, 3/24)