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Moderna, Inc. today announced clinical program updates focusing on Lyme disease, a global health issue impacting about 120,000 people in the U.S. and Europe annually.

To address Lyme's biological complexity, Moderna is advancing a seven-valent approach with two Lyme disease vaccine candidates that will be developed in parallel.

Moderna announced on April 11, 2023, new vaccine candidates, mRNA-1982 and mRNA-1975, represent the Company's first application of its mRNA technology to bacterial pathogens such as Lyme disease.

"Our mRNA platform has changed medicine and will continue to have a major impact on global health. Today we are excited to announce multiple new vaccine candidates, including for enteric viruses, such as norovirus, and targeting Lyme disease, our first bacterial vaccine," said Stéphane Bancel, Chief Executive Officer of Moderna, in a related press release.

mRNA-1982 is designed to elicit antibodies specific for Borrelia burgdorferi, which causes almost all Lyme disease in the U.S.

While mRNA-1975 is designed to elicit antibodies specific for the four major Borrelia species causing disease in the U.S. and Europe.

Lyme disease burden follows a bimodal age distribution, affecting mainly children under 15 and older adults. Patients can develop a rash, fever, headaches, fatigue, joint pain, swelling, stiffness, and headaches.

Older adults appear to have higher odds of unfavorable treatment response than younger patients, and neurologic manifestations are more common at presentation for this more aging adult population.

Currently, the U.S. Food and Drug Administration has not approved a Lyme disease vaccine.

However, VLA15, a multivalent Lyme disease vaccine candidate produced by Pfizer In. and Valneva SE, is conducting late-stage clinical research.

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SARS-CoV-2 XBB.1.5 accounts for 52% of sequenced lineages

Lyme Disease Outbreaks

Lyme Disease Outbreaks December 2025

Lyme disease (Lyme borreliosis) is a bacterial disease transmitted to humans through the bite of infected ticks. Lyme disease is common in Europe, the United Kingdom, and the United States, according to the World Health Organization (WHO). In 1977, the first 51 cases of Lyme arthritis were reported, and the Ixodes scapularis (black-legged) tick was linked to the discovery of the Lyme disease in Connecticut.

As of 2025, the U.S. Centers for Disease Control and Prevention (CDC) publishes the Tick Bite Data Tracker, which displays case data, and the CDC published a Lyme disease case map for the U.S. Seperately, the Pennsylvania Department of Health Tickborne Disease Dashboard shows Lyme disease cases peak in June through August. Wisconsin, Vermont, Rhode Island, New Jersey, New YorkNew Hampshire, Maine, Pennsylvania, and Connecticut were the leading states.

The Kay Hagan Tick Act (S.1657) requires the U.S. Department of Health and Human Services to develop a national strategy to address vector-borne diseases, including Tickborne diseases. The CDC reported on February 15, 2024, that Lyme disease cases, the most common vector-borne disease in the United States, increased by 69%, which is 1.7 times the annual average during 2017–2019 in the United States. In November 2024, a study determined that 50% of adult blacklegged ticks carry the bacteria that cause Lyme disease, while up to 25% of the younger (nymph) blacklegged ticks carry the bacteria.

Lyme Disease Outbreaks in the United Kingdom

In the UK, the Health Security Agency says Lyme disease-carrying ticks are most active in the spring and summer. Approximately 4% of ticks in England and Wales are infected with Lyme disease. Lyme Disease UK advises that if you find an embedded tick in your skin, remove it. The longer a tick is left to feed, the greater the chance that it will pass on any diseases it's carrying.

Lyme Disease Outbreaks in Europe

The World Health Organization Europe says the number of Lyme disease cases in Europe has increased steadily, with more than 360,000 cases reported over the last two decades. The highest-risk regions for future expanding tick colonization in Europe were France, Spain, Ukraine, Germany, Italy, Poland, Romania, and the UK.

A 2023 study found that, on average, 128,888 Lyme Disease cases are reported annually in Europe. The national Lyme disease incidence rates were highest in Estonia, Lithuania, Slovenia, and Switzerland (>100more than cases/100,000 Population per year), followed by France and Poland (40-80/100 cases per 000 Population per year), and Finland and Latvia (20-40/100 cases per 000 Population per year). At the subnational level, the highest LD incidence rates (more than 100/100,000 population per year) were observed in areas of Belgium, the Czech Republic, France, Germany, and Poland.

Lyme Disease Causes

Lyme disease is a Tickborne infection caused by a particular species of Borrelia spirochetes. Ticks transmit at least 20 different disease-causing bacteria, viruses, and parasites to people. The risk of contracting a Tickborne infection, including Lyme disease, is determined by the number of ticks in an area, the proportion of ticks that carry the bacteria, and human behavior, such as walking in areas infested with ticks. A study found that the overall risk of developing Lyme borreliosis after a tick bite was 2.2.6% (95% CI 1.4–5.1).

PrecisionVaccinations publishes Lyme disease vaccine news.

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Acute Hepatitis Children 2023

Acute Hepatitis in Children May 2023

The World Health Organization (WHO), the United Kingdom, Europe, Canada, and the U.S. Centers for Disease Control and Prevention (CDC) have reported acute liver inflammation infections of unknown etiology among children. Since the initial report in October 2021, the U.S. CDC has confirmed that 391 cases of an unknown cause are persons under investigation (PUI) in forty-four states, Puerto Rico, and Washington DC, as of April 12, 2023.

Among the reported PUIs in the U.S., about 90% required hospitalization, 6% needed a liver transplant, and 11 died. In addition, preliminary reports indicated that among PUIs receiving adenovirus testing, about 44% were positive. Although there have been previous reports of hepatitis in children with suppressed immune systems infected with adenovirus, adenovirus type 41 is not a common cause of hepatitis in otherwise healthy children. Some estimates suggest that 30-50% of hepatitis cases in children are from unknown causes. Of the pediatric patients with data regarding COVID-19 vaccination status, about 85% were unvaccinated.

Acute Hepatitis Cases 2023

Since its first identification in Scotland in 2022, and as of March 30, 2023, the following countries have reported over 1,000 pediatric patients with acute hepatitis: AustriaArgentinaBelgium, Brazil, Columbia, CyrusDenmarkEngland, FranceGreeceIreland, Italy, Japan, Latvia, Moldovathe NetherlandsNorway, PolandPortugalScotland, SerbiaSingapore, Spain, Sweden, USA, Wales, and the United Kingdom.

Adeno-associated Virus Type 2 (AAV2) in Children

The journal Nature reported on March 30, 2023, a study used PCR testing, viral enrichment-based sequencing, and agnostic metagenomic sequencing to analyze samples from 16 HAdV-positive cases from October 1, 2021, to May 22, 2022, in parallel with 113 controls. In blood from 14 cases, adeno-associated virus 2 (AAV2) sequences were detected in 93% (13 of 14), compared to 4 (3.5%) of 113 controls (P<0.001) and to 0 of 30 patients with hepatitis of defined etiology (P<0.001). In controls, HAdV-41 was detected in blood from 9 (39.1%) of the 23 patients with acute gastroenteritis (without hepatitis), including 8 of 9 patients with positive stool HAdV testing, but co-infection with AAV2 was observed in only 3 (13.0%) of these 23 patients versus 93% of cases (P<0.001). Co-infections by Epstein-Barr virus, human herpesvirus 6, and/or enterovirus A71 were also detected in 12 (85.7%) of 14 cases, with higher herpesvirus detection in cases versus controls (P<0.001). Our findings suggest that the severity of the disease is related to co-infections involving AAV2 and one or more helper viruses.

Adenovirus Infections Children

Adenovirus has been the most frequently detected pathogen, noted in 193 (52%) of 368 cases in Europe, reported a study published by The Lancet Microbe on September 1, 2022. In children, adenoviruses most often cause infections in the respiratory system, but they also cause digestive tract infections. According to the CDC, there is no specific medical treatment for adenovirus infections, and antibiotics may not work on adenoviruses. Dr. Arun Kumarendu Singh, associated with AIIMS, Jodhpur, said, "Unlike COVID, children below ten are susceptible to Adenovirus. Among them, those below two years of age are more vulnerable," Singh told PTI over the phone on February 21, 2023.

Circovirus in Human Hepatitis

The U.S. CDC reported that in March 2022, a 61-year-old woman in France who had received a heart-lung transplant sought treatment for chronic hepatitis, mainly characterized by increased liver enzymes. After ruling out common etiologies, we used metagenomic next-generation sequencing to analyze a liver biopsy sample and identified an unknown species of circovirus, tentatively named human circovirus 1 (HCirV-1). We found no other viral or bacterial sequences. HCirV-1 shared 70% amino acid identity with the closest known viral sequences. The viral genome was undetectable in blood samples from 2017–2019, then became detectable at low levels in September 2020 and peaked at very high titers (1010 genome copies/mL) in January 2022. In March 2022, we found >108 genome copies/g or mL in the liver and blood, concomitant with hepatic cytolysis. In addition, we detected HCirV-1 transcripts in 2% of hepatocytes, demonstrating viral replication and supporting the role of HCirV-1 in liver damage.

Hepatitis Vaccines

Hepatitis vaccine news is posted at this link.

Acute Hepatitis Children News

May 1, 2023 - Inactivated Enterovirus Type 71 Vaccine Inlive® has been authorized for children in Indonesia

March 31, 2023 - The Conversation published an article that suggests strongly that AAV2, HAdV F41, and the immune response to one or both of the identified viruses underlie the cases of hepatitis seen around the world.

March 30, 2023 - @HelenBranswell Tweeted new studies found the presence of adeno-associated virus 2 (AAV2) in the blood and liver tissues of a number of affected children. They also identified the presence of adenoviruses or herpes viruses.

January 23, 2023 - The Institut Pasteur scientists identified a previously unknown species of circovirus, provisionally named human circovirus 1 (HCirV-1). In March 2022, they found >108 genome copies/g or mL in the liver and blood, concomitant with hepatic cytolysis. Furthermore, we detected HCirV-1 transcripts in 2% of hepatocytes, demonstrating viral replication and supporting the role of HCirV-1 in liver damage.

December 4, 2022 - The peer-review journal Vaccines published a study: Vaccine-Related Autoimmune Hepatitis: Emerging Association with SARS-CoV-2 Vaccination or Coincidence? Early diagnosis is mandatory and should be considered in patients with acute or chronic hepatitis after SARS-CoV-2 vaccination, especially those with pre-existing liver disease.

September 6, 2022 - Local media in Spain reported there had been (48) pediatric cases of unknown hepatitis-like illness in 2022, with (3) liver transplants and (2) related fatalities.

September 1, 2022 - The Lancet Microbe published New guidance for researching acute hepatitis in children. So far, adenovirus has been the most frequently detected pathogen, noted in 193 (52%) of 368 cases in Europe.

August 18, 2022 - The NEJM published an ORIGINAL ARTICLE: A Case Series of Children with Acute Hepatitis and Human Adenovirus Infection. CONCLUSIONS: Human adenovirus viremia was present in the majority of children with acute hepatitis of unknown cause admitted to Children's of Alabama from October 2021 to February 2022, but whether human adenovirus was causative remains unclear. Sequencing results suggest that if human adenovirus was causative, this was not an outbreak driven by a single strain. A related Editorial added: Many other viruses, some quite commonly encountered during childhood, are hepatotropic and, in a minority of patients, may cause illness that can escalate in severity. In these cases, liver damage manifests as elevations in serum levels of liver enzymes.

August 5, 2022 - The AP reported Spain's health ministry had reported 46 cases, including three children who needed liver transplants. Of these three, two patients died.

July 29, 2022 - This ECDC/WHO report provides an overview of the cases of hepatitis of unknown origin in children aged 16 years and below reported to ECDC and the WHO Regional Office for Europe for the period up to 28 July 2022, including the 27 countries of the European Union and the additional three countries of the European Economic Area. Since the first alert launched by the UK on 5 April 2022, cases of hepatitis of unknown etiology in children have been reported from multiple countries worldwide, it is unclear whether all cases identified following the alert are part of an actual increase compared to the baseline rate of hepatitis of unknown etiology in children.

July 28, 2022 - The UK Health Security Agency confirmed 270 cases of sudden onset hepatitis in children aged ten and younger. Of these children, 15 have received a liver transplant; none has died. The rate at which new cases are reported has now declined. And the UKHSA published Technical Briefing #4: Investigation into acute hepatitis of unknown etiology in children in England. Adenovirus (64%) remains the most frequently detected potential pathogen in the U.K.'s 270 confirmed cases. And the SARS-CoV-2 virus had been detected in 17%.

July 25, 2022 - MIT Tech Review published: We're starting to understand the mysterious surge of hepatitis in children.

July 1, 2022 - The peer-review journal Nature published: Sudden onset hepatitis in children. The UKHSA has triggered a special Comprehensive Clinical Characterisation Collaboration (ISARIC4C) in response to unexplained hepatitis in children in the UK.

June 28, 2022 - Science.org reported 'a WHO team led by infectious disease physician Philippa Easterbrook this week aims to launch a survey of hepatologists at pediatric liver units and intensive care units around the globe, asking for case counts and data from the prepandemic era as well as from recent months.'

June 24, 2022 - The U.S. CDC published a Morbidity and Mortality Weekly Report - Interim Analysis of Acute Hepatitis of Unknown Etiology in Children. The investigation is ongoing; further clinical data are needed to understand the cause of these (296) cases and to assess the potential association with Adenovirus.

June 24, 2022 - The WHO published - Severe acute hepatitis of unknown etiology in children - Multi-country - The risk at the global level is currently assessed as moderate, considering the etiology of this severe acute hepatitis remains unknown and is being investigated.

June 21, 2022 - The Pan American Health Organization announced new guidance for regional laboratories to contribute to investigating the causes of hepatitis of unknown origin in children. "While this is a severe disease in children and is a cause of concern, its occurrence remains rare," commented Ruben Mayorga at the PAHO. He stressed, however, that it is important to "continue to monitor the situation and investigate probable cases."

June 20, 2022 - Prof Rela and his India-based team were recognized as South Asia's most extensive Paediatric liver transplant program, having performed over 500+ pediatric liver transplantations. "Liver transplantation in children was unheard of and has seen many families suffer. And now, to see how this is made available to the neediest, I must thank the Government of Tamil Nadu for their relentless support."

June 17, 2022 - Since the last ECDC surveillance bulletin, 48 new cases have been reported from eight countries (Austria (one), Greece (three), Ireland (one), Italy (two), the Netherlands (one), Spain (one), Sweden (one), and the United Kingdom (38).

June 17, 2022 - The UKHSA published - Research and analysis: Investigation into acute hepatitis of unknown etiology in children in England: case update.

June 16, 2022 - The U.S. CDC's National Center for Immunization and Respiratory Diseases published a 'Technical Report: Acute Hepatitis of Unknown Cause.'

June 14, 2022 - The U.S. CDC published an early MMWR - Trends in Acute Hepatitis of Unspecified Etiology and Adenovirus Stool Testing Results in Children — U.S., 2017–2022.

June 14, 2022 - The U.S. CDC reported, 'Analyses of four data sources did not indicate recent increases in hepatitis-associated emergency department visits or hospitalizations, liver transplants, or adenovirus types 40/41 percent positivity among U.S. children compared with pre–COVID-19 pandemic levels.' The findings in this CDC report are subject to at least seven limitations.

June 11, 2022 - Portugal's Directorate-General for Health (DGS) recently advised that children with symptoms suggestive of acute hepatitis should urgently attend a hospital.

June 10, 2022 - A study from Tel Aviv University: Long COVID-19 Liver Manifestation in Children. We report five pediatric patients who recovered from COVID-19 and later presented with liver injury. After a thorough workup that excluded other known etiologies, we report two patterns of potentially long COVID-19 liver manifestations in children with common clinical, radiological, and histopathological characteristics.

June 7, 2022 - The World Hepatitis Summit 2022 urges action to eliminate viral hepatitis as unexplained hepatitis cases in children increases globally.

June 2, 2022 - The journal Nature published: A multiancestry genome-wide association study of unexplained chronic ALT elevation as a proxy for nonalcoholic fatty liver disease with histological and radiological validation. Our approach to integrating cALT, histology, and imaging reveals new insights into a genetic liability to NAFLD.

May 31, 2022 - Revive Therapeutics Ltd. announced that in light of the growing cases of acute hepatitis in children, the Company would advance its drug pipeline for inflammatory liver disorders, including Bucillamine in the prevention of ischemia-reperfusion injury during liver transplantation and Cannabidiol for autoimmune hepatitis.

May 27, 2022 - Japan's Ministry of health, labor, and welfare announced the 31st case of acute hepatitis in children of unknown etiology.

May 20, 2022 - Public Health Scotland confirmed that 26 cases of sudden onset hepatitis (liver inflammation) in children aged ten and under had been identified in Scotland since January 2022.

May 20, 2022 - The UKHSA published Technical Briefing document #3 on investigating acute hepatitis cases of unknown etiology in children in England.

May 17, 2022 - The BMJ published an Editorial: Acute hepatitis of unknown origin in children: 'Many leads but few clear answers.'

May 16, 2022 - NanoViricides, Inc. has initiated a program to screen its library of broad-spectrum antiviral nanoviricides against human Adenovirus 41 Type F (hAd41-F), believed to be strongly associated with the occurrence of severe hepatitis syndrome in some children, causing liver transplants as well as fatalities in large percentages of cases.

May 16, 2022 - Isabella Eckerle, co-Head of the Centre for Emerging Viral Diseases at the Geneva University Hospitals, said the possibility of acute hepatitis in children following COVID-19 infection could not be ruled out.

May 13, 2022 - The Lancet published: Severe acute hepatitis in children: investigate SARS-CoV-2 superantigens. 'We suggest that children with acute hepatitis be investigated for SARS-CoV-2 persistence in stool, T-cell receptor skewing, and IFN-γ upregulation because this could provide evidence of a SARS-CoV-2 superantigen mechanism in an adenovirus-41F-sensitised host. If evidence of superantigen-mediated immune activation is found, immunomodulatory therapies should be considered in children with severe acute hepatitis.'

May 12, 2022 - The Lancet published: Explaining unexplained hepatitis in children.

May 11, 2022 - The U.S. CDC issued Health Alert Network Health Update CDCHAN-00465 with information about an epidemiologic investigation of pediatric cases of hepatitis of unknown etiology in the U.S. Where possible, clinical specimens should be tested locally to ensure timely results for patient care. Nucleic acid amplification testing, such as polymerase chain reaction, is preferred for adenovirus detection (currently unavailable for FFPE liver biopsy or native liver explant). In addition, testing whole blood by PCR is more sensitive and preferred over testing plasma by PCR.

May 9, 2022 - Indonesia identified 15 cases of acute hepatitis of unknown origin after reporting three pediatric fatalities.

May 6, 2022 - Staff from the U.S. CDC conducted a telebriefing where Dr. Jay Butler, the deputy director of infectious diseases, commented, 'these pediatric cases have been reported since October 2021, with initial cases confirmed in Alabama. Of the 109 diagnosed children, 90% were hospitalized, 14% required liver transplants, five children have died, with some children are still hospitalized.

April 29, 2022 - The CDC reported: The Alabama cluster review: cases began Oct. 1, 2021, with no geographical or epidemiological links between the children who were <= age 5; Adenovirus was detected in all children, with type 41 detected in five specimens; three patients developed acute liver failure, two of whom were treated with cidofovir (off-label use) and steroids, and underwent liver transplantation; at admission, eight patients had scleral icterus, seven had hepatomegaly, six had jaundice, and one had encephalopathy.

April 29, 2022 - Garcetin Madrid reported that in Spain, between January 2022 and April 29, 2022, twenty-two acute hepatitis-like cases have been detected with no epidemiological link. A total of 8 have been in the Community of Madrid. In one case, it has been possible to determine through genomic sequencing that the Adenovirus is type 2.

April 26, 2022 - The Romanian Ministry of Health announced a 5-year-old child from the Bucharest-Ilfov area was admitted to a specialized hospital on April 4, 2022, for severe acute hepatitis.

April 20, 2022 - The Journal of Virology published: SARS-CoV-2 vaccination can elicit a CD8 T-cell dominant hepatitis. In this case report, we show that highly activated T cells accumulate and are evenly distributed in the different areas of the liver in a patient with liver inflammation following SARS-CoV-2 vaccination. Moreover, within these liver-infiltrating T cells, we observed an enrichment of T cells reactive to SARS-CoV-2, suggesting that these vaccine-induced cells can contribute to liver inflammation. Autoimmune-hepatitis-like disease after vaccination against SARS-CoV-2 is now recognized as a rare adverse event not identified in early trials. The widespread use of the vaccine with the administration of hundreds of millions of doses worldwide also raises questions of causality vs. coincidence.

April 21, 2022 - The U.S. CDC published Health Advisory #CDCHAN-00462 - Recommendations for Adenovirus Testing and Reporting of Children with Acute Hepatitis of Unknown Etiology. A possible association between pediatric hepatitis and adenovirus 41 infection is under investigation.

April 20, 2022 - A peer-reviewed Research Article by the Journal of Hepatology: SARS-CoV-2 vaccination can elicit a CD8 T-cell dominant hepatitis. Conclusions - COVID-19 vaccination can elicit a distinct T cell-dominant immune-mediated hepatitis with a unique pathomechanism associated with vaccination-induced antigen-specific tissue-resident immunity requiring systemic immunosuppression.

April 18, 2022 - The Alabama Department of Public Health recently announced it is investigating an increase in hepatitis in nine young children in Alabama, with a potential association with Adenovirus 41.

April 14, 2022 - The number of children presenting acutely with abnormal liver function tests in March 2022 to the Royal Hospital for Children, Glasgow, were compared with those in March 2019 as well as March 2020 and 2021, confirming higher-than-expected numbers in 2022 among children under five years of age. Furthermore, the number presented in March 2022 exceeded the total number expected for Scotland over one year.

December 27, 2021 - The journal Immunology published: New-onset autoimmune phenomena post-COVID-19 vaccination, which summarized the emerging evidence about autoimmune manifestations occurring in response to certain COVID-19 vaccines. 

March 12, 2019 - Adenovirus in solid organ transplant recipients: Guidelines from the American Society of Transplantation Infectious Diseases Community of PracticeProspective randomized clinical trials do not support the use of antiviral therapy. However, most transplant centers consider intravenous cidofovir the standard practice for treating severe, progressive, or disseminated adenovirus disease. In addition, intravenous immunoglobulin may be beneficial, primarily in a select group of patients with hypogammaglobulinemia.

October 6, 2017 - U.S. CDC MMWR: Human Adenovirus (41) Surveillance — the United States, 2003–2016.

August 4, 2017 - Epidemic Keratoconjunctivitis Outbreak Associated with Human Adenovirus Type 8 — U.S. Virgin Islands, June–November 2016.

June 2017 - The American Journal of Surgical Pathology: Adenovirus Hepatitis - Clinicopathologic Analysis of 12 Consecutive Cases From a Single Institution. 

January 2007 - Treatment of Adenovirus Disease in Stem Cell Transplant Recipients with Cidofovir. In conclusion, early treatment of AdV disease with cidofovir inhibits viral replication in vivo and reduces mortality in allogeneic SCT recipients compared with historical data.

August 1996 - U.S. NIH - Adenovirus 41 replication: cell-related differences in viral gene transcription.

August 1994 - This paper used various approaches to characterize the two proteins and determine whether both fibers were expressed in infected cells and viral particles. DNA sequencing of the subgroup F human adenovirus serotype 41 (TAK, Ad41) fiber gene revealed the presence of two adjacent open reading frames encoding information for proteins with molecular weights of 60.6 kDa and 41.4 kDa (Pieniazek et al.; Nucleic Acids Res. 18: p. 1901, 1990).

Adenovirus Vaccines

There is an adenovector vaccine available for most U.S. military personnel. In addition, the U.S. Department of Defense recommends it for military recruits entering basic training. It may also be recommended for other military personnel at high risk for adenovirus infection. Initially approved by the U.S. FDA in 2011, the Johnson & Johnson (Barr Labs, Inc.) adenovirus vaccine contains live adenovirus Type 4 and Type 7. The vaccine (BL 125296) comes as two tablets, taken orally, and should be swallowed whole, not chewed or crushed. The safety and effectiveness of Adenovirus Type 4 and Type 7 Vaccine in immunocompromised individuals have not been evaluated. In Canada, the Adenovirus Vaccine (W6369-19A009/A) was approved in 2018.

Autoimmune Hepatitis

Autoimmune hepatitis (AIH) can occur in individuals where environmental factors trigger an immune-mediated reaction against hepatocytes. Vaccines are a very rare cause of AIH. There are two clinically relevant types of AIH, including type 1 and type 2. Type 1 AIH, also referred to as the classic type, is typically diagnosed in adulthood, whereas type 2 is diagnosed during childhood. Both types are treated similarly; however, type 2 AIH can be more severe and difficult to control. 

Nonalcoholic Steatohepatitis

Nonalcoholic fatty liver disease (NAFLD) is a condition in which fat builds up in your liver. The more severe form of NAFLD is called nonalcoholic steatohepatitis (NASH). NASH causes the liver to swell and become damaged. NAFLD is one of the most common forms of chronic liver disease in children and adolescents, possibly related to environmental and genetic reasons.

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Lyme Disease Vaccines

Lyme Disease Vaccine Candidates

Lyme disease vaccine research includes early-stage discovery and novel vaccine formulations, including tick saliva-based approaches. In addition, the U.S. National Institutes of Health (NIH) published a Strategic Plan for Tickborne Disease Research that prioritizes vaccines needed to prevent diseases. As of March 2025, the U.S. Food and Drug Administration (FDA), the European Medicines Agency (EMA), and the United Kingdom have not approved a preventive Lyme disease vaccine. The only human Lyme disease vaccine marketed in the U.S. was LYMERix®, which was discontinued in 2002.

According to IMARC, the Lyme disease market was worth $594 million in 2023. Over the next decade, it is expected to exceed $1 billion by 2034, exhibiting a growth rate of 6.45%.

Lyme Disease Vaccine Candidates 2025

VLA15, a multivalent Lyme Disease vaccine candidate produced by Pfizer Inc. and Valneva SE, targets Borrelia's outer surface protein A and conducts late-stage clinical trials.

Moderna Inc. is advancing a seven-valent approach with two Lyme disease vaccine candidates that will be developed in parallel. mRNA-1982 is designed to elicit antibodies specific for Borrelia burgdorferi, which causes almost all Lyme disease in the U.S. mRNA-1975 is designed to elicit antibodies specific for the four major Borrelia species causing disease in the U.S. and Europe.

TP-05 is a novel investigative oral therapeutic that could potentially prevent Lyme disease. It is an oral systemic formulation of lotilaner, a well-characterized anti-parasitic agent that selectively inhibits parasite-specific GABA-CI channels.

The National School of Tropical Medicine at Baylor College of Medicine and Texas Children's Hospital's Center for Vaccine Development received an $860,000 grant from the U.S. Department of Defense to develop a recombinant protein vaccine for Lyme disease. The Congressional Director of Medical Research Programs supports this work through the DoD Tick-borne Disease Research Program. W81XWH-20-1-0913. 

Penn Medicine's Lyme disease vaccine candidate uses mRNA-LNP platform technology pioneered at Penn. After a single immunization, the OspA mRNA-LNP vaccine induced superior humoral and cell-mediated immune responses in mice. These potent immune responses resulted in protection against bacterial infection.

CyanVac's intranasal parainfluenza virus 5 (PIV5)-based vaccine for Lyme Disease was found in a study to induce protection against a multi-strain Borrelia burgdorferi tick challenge in mice. The Lyme disease project was a collaboration between CyanVac and Immuno Technologies, Inc. and was supported by the National Institute of Allergy and Infectious Disease.

Lyme Disease Diagnostics

Many tick-borne infections are misdiagnosed because their nonspecific symptoms mirror other illnesses. In addition, several Borrelia sub-species and strains exist, and researchers continue to discover new species.

Lyme Disease Overview

According to the U.S. NIH, Borreliosis is an infectious disease caused by spiral-shaped bacteria known as Borreliae, often carried by ticks. The species of Borreliae known to cause disease in humans are split into the following two groups: B. burgdorferi sensu lato, which causes Lyme disease, and Relapsing Fever Borrelia, which causes Tick-borne Relapsing Fever.

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Zika Outbreaks

Zika Outbreaks December 2025

Zika virus disease (ZIKV) was first recognized in Uganda in 1947, with the initial human infection confirmed in 1952. In 2016, the World Health Organization (WHO) declared the Zika virus epidemic a public health emergency of international concern. Since then, Zika outbreaks have been reported in tropical Africa, Southeast Asia, the Pacific Islands, in the Americas, and continue to occur in 92 countries and territories globally. The WHO published a Global Strategic Preparedness, Readiness, and Response Plan for Aedes-borne arboviruses on January 20, 2025. Studies predict that because of virus-carrying mosquitoes expanding into new geographic areas, about 1.3 billion people could be impacted by Zika by 2050.

As of 2025, the U.S. Centers for Disease Control and Prevention (CDC) Yellow Book states that international travelers with suspected Zika infection should be tested with real-time polymerase chain reaction or an NS1 antigen test. In 2025, public health and commercial lab testing services can detect Zika infections in people.

Zika in the United States

As of 2025, the Pan American Health Organization (PAHO) reported travel-related Zika cases in the United States. The Hawaiʻi Department of Health announced on May 27, 2025, that it is investigating two travel-related Zika cases, and Puerto Rico has been categorized as having a risk of Zika transmission for several years. As of December 31, 2024, the U.S. CDC reported 19 non-congenital Zika cases among U.S. residents (1 imported case in Texas). In 2023, the CDC reported five non-congenital cases among U.S. residents and 27 in U.S. territories. The  CDC says Zika-spreading mosquitoes are found throughout Puerto Rico, where the Department of Health says 16 cases were reported in 2024. 

Zika Outbreaks in The Americas

The PAHO has confirmed local transmission of the Zika virus in 52 countries and territories in the Americas since 2015. As of December 2025, over 25,800 Zika cases and four related fatalities were reported in the Americas this year. The PAHO reported 42,127 ZIka cases and two associated fatalities in the Americas in 2024, with the highest proportion of Zika cases reported in ArgentinaBrazil, Bolivia, Colombia, and Costa Rica. The PAHO reported over 37,659 Zika cases in the Americas in 2023. In 2021, the U.S. CDC removed its Level 2—Practice Enhanced Precautions notice regarding Argentina's Zika outbreak.

Zika in Europe

The European Centre for Disease Prevention and Control (ECDC) says the Zika virus is not endemic in mainland Europe. In August 2025, France reported four travel-related Zika cases. In November 2024, Italy reported 7 imported Zika cases this year. On September 11, 2024, France reported five imported cases of Zika in 3 departments colonized by Aedes albopictus. In 2022, the European CDC reported that 31,453 Zika patients were confirmed in 13 of 52 countries and territories. In addition, the WHO reported in 2019 that French authorities confirmed an autochthonous Zika virus case in Hyeres, Var department.

Zika United Kingdom

Zika virus disease cases also decreased to 4 cases in the first half of 2025. Zika cases increased to 16 in England, Wales, and Northern Ireland in 2024, up from 8 in 2023. Thailand (5 cases) and Singapore (2) were the most frequently reported travel countries. The UK Health Security Agency (UKHSA) issued a warning on March 21, 2024, concerning Zika outbreaks. Travel-related Zika cases in the UK peaked in 2016 with 725 cases.

Zika Virus Infection Impact

According to the WHO, there is scientific consensus that the Zika virus is transmitted to people by mosquitoes of the genus Aedes. Since 2013, 31 countries and territories have reported cases of congenital microcephaly and other central nervous system malformations associated with Zika virus infection. The WHO reports that Zika virus lineages, the African lineage and the Asian lineage, have recently spread in the Pacific and the Americas. Zika infections can cause microcephaly, Guillain-Barré syndrome (GBS), and other central nervous system malformations. Although the Zika outbreak in southern Brazil has slowed in recent years, live births with microcephaly continue to be reported.

The U.S. CDC published Research, Volume 30, Number 2—February 2024: a temporal phylogenetic analysis revealed limited within-host diversity among most ZIKV-persistent-infected associated samples. The researchers detected unusual viral diversity, uncovering the existence of divergent genomes within the same patient. During pregnancy, healthcare providers can monitor the fetus for signs of congenital Zika virus infection.

An Original Investigation published by JAMA Public Health on January 23, 2025, found that children younger than 5 years born with congenital Zika syndrome (CZS) had a 13.10-fold higher hazard of death compared with those without CZS. The cause-specific mortality hazard ratios were 30.28 for respiratory diseases, 28.26 for infectious and parasitic diseases, and 57.11 for nervous system diseases. Research published in Communications Biology and the Liverpool School of Tropical Medicine on January 20, 2025, reported that the Zika virus hijacks the skin of its human host to send chemical signals that lure more mosquitoes to infect and spread the disease further.

Congenital Zika Syndrome

A population-based study of mortality rates among children younger than 5 years old in Brazil, published in JAMA Network Open in January 2025, showed that children with congenital Zika syndrome (CZS) had a 13-fold higher risk of death compared with those without CZS.

The 2015–2016 ZIKV outbreak in the Region of the Americas revealed the ability of ZIKV from the Asian lineage to cause congenital disabilities, generically called CZS, which caused severe congenital disabilities of the brain and eyes, including severe microcephaly. A study published in Pediatrics in January 2025 concluded that children exposed to ZIKV in utero, even without CZS, demonstrate a greater risk for neurodevelopmental delay in early childhood, with the timing of maternal infection being a significant predictive risk factor. The International Journal of Infectious Diseases published a study in 2025 showing that children with CZS are more likely to experience frequent hospitalizations in early childhood. Scientists have reported that ZIKV RNA is detectable in the semen of infected men for months and is found in newborn children.

Zika Vaccines

As of 2025, no approved Zika vaccine exists; however, vaccine candidates are currently being tested in clinical trials.

6 min read
Last Reviewed: 
Wednesday, December 3, 2025 - 09:10
Description: 
Zika outbreaks in 2025 are caused by mosquitoes transmitting virus to people that cause microcephaly in children.

Travel Diseases 2025

Travel Diseases December 2025

Vaccine-preventable disease outbreaks, such as polio, yellow fever, Ebola, measles, cholera, and chikungunya, continue to disrupt international travel in 2025, says the U.S. Centers for Disease Control and Prevention (CDC). In the United States, the National Notifiable Diseases Surveillance System collects data on reportable diseases from various jurisdictions. As of December 2025, the CDC published Travel Health Advisories and digital maps indicating disease outbreaks in multiple countries.

The World Health Organization (WHO) and the UK Health Security Agency (UKHSA) emphasize the importance of checking your destination before travel and staying prepared by staying up to date with the latest outbreaks and events. The UKHSA published an analysis of travel-related diseases in the United Kingdom for the first half of 2025. The WHO and the Pan American Health Organization (PAHO) publish weekly Epidemiological Updates for mosquito-transmitted diseases in 2025. The WHO publishes global trends and total numbers in reported cases of selected vaccine-preventable diseases.

Travel Diseases

As of 2025, the U.S. Food and Drug Administration (FDA) has approved vaccines targeting travel-related diseases, such as the following:

Chagas Disease - Researchers from Texas A&M University, the University of Florida, and the Texas Department of State Health Services say the time is now to recognize Chagas disease as endemic in the U.S. As of 2025, no vaccines are available to prevent Chagas disease.

Chikungunya: Chikungunya is a viral disease transmitted to humans by mosquitoes infected with the Chikungunya virus (CHIKV). Outbreaks are primarily found in Africa, Asia, Brazil, and the Indian subcontinent. In 2023, the U.S. FDA approved a CHIKV preventive vaccine, nd in 2025, a second one, VIMKUNYA® 2025.

Cholera: The WHO has recorded seven cholera pandemics over the past two centuries, with the current (7th) cholera epidemic, which began in 1961, expected to continue in 45 countries by 2025. WHO-prequalified oral cholera vaccines (OCV), such as DUKORAL, are available. VaxChora® became available in the U.S. in late 2023.

Dengue: The dengue virus is transmitted to humans through the bite of infected mosquitoes. There are four Dengue serotypes, and any of them can infect you.

Ebola: Ebola virus disease is a rare but often fatal illness in humans. The Ervebo® vaccine was approved by the U.S. FDA in 2020. 

Hepatitis: Hepatitis is an inflammation of the liver. The five main strains of hepatitis viruses include hepatitis A, hepatitis B, hepatitis C, hepatitis D, and hepatitis E. The CDC updated hepatitis vaccination schedules for children, adolescents, and adults. 

Influenza: Various influenza viruses continually spread worldwide. Several FDA-approved flu shots are available in 2025.

Japanese Encephalitis (JE) is a severe virus that spreads to people through the bites of infected mosquitoes. FDA-approved JE vaccines are available in the U.S.

Lassa Fever is an acute viral infection that originates and spreads through contact with a typical African rodent, such as the multimammate rat. As of 2023, the U.S. FDA has not approved a Lassa fever vaccine.

Lyme disease is a Tickborne disease common in Europe and the United States, transmitted to humans through the bite of infected ticks. No vaccine has been approved in 2025.

Malaria: A life-threatening disease caused by parasites transmitted to people through the bites of infected female Anopheles mosquitoes. It is preventable with the Mosquirix and R21/Matrix-M malaria vaccines, which are available in Africa, not the U.S.

Marburg: Marburg virus disease (MVD) is a severe human disease caused by the Marburg virus. Recent outbreaks in Africa have caused MVD. As of 2025, the FDA has not approved a vaccine for MVD.

Measles: Highly contagious, severe viral Disease; vaccines (MMR-II and Priorix) are available throughout the U.S., but the Disease poses a risk to international travelers visiting countries such as India.

Meningococcal: Vaccines can help prevent meningococcal Disease, which is any illness caused by the bacterium Neisseria meningitidis.

MERS: Middle East Respiratory Syndrome vaccines are not approved in 2025, but several vaccine candidates are being tested in clinical trials.

Mpox: Mpox is caused by the mpox virus, and outbreaks began in May 2022 and continue in 2023. Authorized vaccines such as JYNNEOS® are available in various countries in 2023.

Oropouche is a known disease that is emerging in parts of South America, Central America, and the Caribbean. As of July 2025, a commercial test was announced. Reverse transcription PCR testing can identify the RNA of the virus during the early stages of infection, aiding in diagnosis. Serology testing, which identifies antibodies produced by the immune system in response to the virus, can assist in diagnosing the virus in later stages of infection.

Polio is a highly infectious disease caused by the poliovirus. There is no cure for polio, but vaccines can prevent it. Canada, Israel, Germany, the UK, New York, Spain, and various African and European countries have detected the rabies virus in wastewater and in expanded vaccination programs. Rabies is a vaccine-preventable viral disease in over 150 countries and territories. It is present on all continents except Antarctica, with over 95% of human deaths occurring in the Asia and African regions. It is spread to people and animals through bites or scratches, usually via saliva. Dogs are responsible for up to 99% of rabies transmission to humans. 

Rift Valley Fever: An epidemic in Africa that can be fatal to humans. As of 2023, no vaccines are available for human use. However, the ThVF vaccine candidate was found safe, well-tolerated, and immunogenic when administered as a single dose in this University of Oxford phase 1 study population.

Rotavirus: Four rotavirus strains are WHO prequalified.

Tickborne encephalitis: The Tickborne encephalitis virus belongs to the family Flaviviridae. Four FDA-approved vaccines are currently available.

Typhoid: Typhoid fever is a life-threatening infection caused by Salmonella Typhi. It is usually spread through contaminated food or water. One FDA-approved vaccine has been used for many years to prevent typhoid.

Tuberculosis (TB) is a potentially severe infectious disease that primarily affects the lungs. The Bacillus Calmette-Guérin (BCG) vaccine helps prevent TB. 

West Nile Virus: Phoenix, Arizona, has become a West Nile Virus (WNV) hot spot in the U.S. in 2023. However, the U.S. FDA has not authorized a WNV vaccine for prevention.

Yellow Fever: Yellow fever is an acute viral hemorrhagic disease transmitted by infected mosquitoes. A small proportion of patients who contract the virus develop severe symptoms, and approximately half die within 7 to 10 days. Yellow fever vaccines (YF-Vax® and Stamaril®) are available worldwide.

Zika: Zika virus outbreaks in Brazil, India, and Puretro Rico are expected to continue in 2025. However, as of July 2025, no approved Zika vaccines are available.

Travel Vaccine Appointments

Request a pre-departure travel vaccination advisory appointment with a healthcare professional using this weblink.

6 min read
Last Reviewed: 
Saturday, December 13, 2025 - 20:10
Description: 
Vaccination prevents yellow fever, polio, malaria, measles, mpox, dengue, chikungunya diseases.
Condition: 

Lyme PrEP Antibody Treatment

Lyme PrEP Antibody Treatment 2022

Lyme PrEP uses a single human antibody, or blood protein, to kill the bacteria in the tick’s gut while the tick drinks its victim’s blood before the bacteria can get into the human host. The testing pre-exposure prophylaxis delivers a monoclonal antibody to provide immediate immunity against Lyme disease.

A panel of anti-OspA human mAbs (HuMAbs) as potential prophylaxis for Lyme disease was developed. In particular, HuMAb 2217 was shown to be borreliacidal (EC50 < 1 nM) against B. burgdorferi, B. afzelii, and B. garinii, the three main genospecies endemic in the United States, Europe, and Asia. In addition, when passively administered to mice before challenge with B. burgdorferi–infected Ixodes ticks, HuMAb 2217 completely prevented transmission after a single dose of 10 mg/kg.

One challenge to developing 2217 for Lyme disease prevention is to ensure that the antibody sustains a protective plasma concentration for the entire tick season.

HuMab 2217 was modified (HuMab 2217LS) to successfully double its half-life, which could provide sufficient protection during the Lyme disease season.

Lyme PrEP Antibody Treatment Indication

Lyme PrEP would be indicated for those populations living in areas where black-legged or deer ticks are found. It prevents infection by delivering a single human anti-Lyme antibody, or blood protein, directly to a person rather than triggering their immune system to make many antibodies as vaccines do. If a person’s blood contains the correct antibody against the bacteria, the antibody can kill Borrelia in the tick’s gut before the bacteria has a chance to travel to the person.

Lyme disease in humans is characterized by erythema migrans (EM), fever; fatigue; musculoskeletal pain; and the potential for neurological, cardiac, or joint manifestations. The CDC has estimated that over 476,000 Americans are diagnosed with and treated for Lyme disease each year.

Lyme PrEP Antibody Treatment Dosage

Phase 1 trial indicates that a single shot will give protection for the necessary amount of time but will be confirmed during the later phases of the clinical trials.

Lyme PrEP Antibody Treatment Side Effects

Unlike a vaccine, which induces antibodies that may not contribute to protection but can cause side effects, the Lyme PrEP approach uses a single, defined antibody, thus reducing the risk of side effects.

Lyme PrEP Antibody Treatment News 2020 - 2022

May 5, 2022 - A Phase I clinical trial of a preventive Lyme disease shot developed by MassBiologics of UMass Chan Medical School is nearing completion, and the subsequent trial phase may begin as soon as next spring, according to Mark Klempner, MD, professor of medicine and former executive vice chancellor for MassBiologics.

March 11, 2021 - Video: Preventive shot for Lyme disease, now in a clinical trial, explained.

June 4, 2020 - A Lyme disease vaccine doesn’t exist, but a yearly antibody shot shows promise at preventing infection.

Lyme PrEP Antibody Treatment Clinical Trial

LymePrEP Phase 1 clinical trial. The trial title is First Clinical Study of the Safety and Blood Levels of a Human Monoclonal Antibody (2217LS) Against Lyme Disease Bacteria in Healthy People.  “The goals for the Phase I clinical trial are to test for the safety of Lyme PrEP and to determine how long it lasts in the bloodstream in humans. During the Phase I trial, 48 volunteers who had never been exposed to Lyme disease participated in the trial in Nebraska, where the disease is not endemic. The Phase I trial will end in August.

The Phase II-III clinical trial is under development and is anticipated to begin in Spring 2023.

0 min read
Generic: 
Lyme PrEP
Drug Class: 
Monoclonal Antibody
Condition: 
Last Reviewed: 
Thursday, May 12, 2022 - 10:25
Abbreviation: 
2217LS
Status: 
Manufacturer Country ID: 

Ivermectin

Ivermectin

Ivermectin (STROMECTOL®) is a U.S. Food and Drug Administration (FDA) approved semisynthetic, anthelmintic agent for oral administration. Ivermectin is derived from the avermectins, a class of highly active, broad-spectrum, antiparasitic agents isolated from the fermentation products of Streptomyces avermitilis. Ivermectin is a mixture containing at least 90% 5-Odemethyl-22,23-dihydroavermectin A1a and less than 10% 5-O-demethyl-25-de(1-methylpropyl)-22,23-dihydro25-(1-methylethyl)avermectin A1a, generally referred to as 22,23-dihydroavermectin B1a and B1b, or H2B1a and H2B1b, respectively.

On March 6, 2023, the FDA confirmed that Ivermectin is an approved antiparasitic drug used to treat several neglected tropical diseases, including onchocerciasis, helminthiases, scabies, and strongyloidiasis, all of which are caused by parasitic worms. Ivermectin has been widely used for these indications and is generally well tolerated. Ivermectin is usually well tolerated when used at appropriate doses for approved indications.

Ivermectin Indication

The U.S. CDC states that Ivermectin is indicated for the treatment of the following infections: Strongyloidiasis of the intestinal tract. Ivermectin is indicated for treating intestinal (i.e., non-disseminated) strongyloidiasis caused by the nematode parasite Strongyloides stercoralis. This indication is based on clinical studies of comparative and open-label designs, in which 64-100% of infected patients were cured following a single 200-mcg/kg dose of Ivermectin.

In addition, some topical forms of Ivermectin are approved to treat external parasites, such as head lice, and skin conditions like rosacea. Zydus Lifesciences Limited (formerly Cadila Healthcare Limited) received final approval from the USFDA to market Ivermectin Cream, 1% (Soolantra). Ivermectin Cream is used the treat inflammatory lesions of rosacea. Soolantra will be manufactured at the group's topical manufacturing facility in Ahmedabad, India.

Ivermectin is contraindicated for those five years of age or those weighing less than 15 kilograms and individuals with liver or kidney disease.

ivermectin Scabies

The results of a multicenter trial indicate that Ivermectin can be safely used in young children for scabies treatment. "Outcomes from the Ivermectin Safety in Small Children trial will hopefully provide greater reassurance that ivermectin can be safely used in children weighing less than 15 kilograms," lead study author Kevin Kobylinski, PhD, a University of Oxford honorary visiting research fellow with the Mahidol Oxford Tropical Medicine Research Unit in Bangkok, said in a press release on November 10, 2025.

Ivermectin Malaria

A study published in the New England Journal of Medicine on July 23, 2025, concluded that Ivermectin reduced the incidence of malaria by 26% in a cluster-randomized trial (BOHEMIA) conducted in Kenya, Africa. Previously, The Lancet published the results of a 2019 study. The primary analysis of this study revealed that the mean number of clinical malaria episodes per child was approximately 20% lower in the intervention group than in the control group during the 18-week treatment period. Two groups of clusters (three in Mozambique) were randomized to receive (a) ivermectin in humans, (b) ivermectin in humans + livestock (only in Mozambique), or (c) albendazole control. WHO's PPC states that the desired efficacy of an endectocide as stand-alone insecticide in areas of high to moderate transmission is at least 20% reduction in the incidence of clinical malaria (as primary outcome) and incidence of infection (as secondary outcome) in children under 5 years old (the highest incidence age-group in areas with high-transmission), lasting for at least 1 month following a single regimen.

Ivermectin Dengue

Ivermectin has been previously shown to inhibit all four dengue serotypes in vitro by blocking the host nuclear import proteins that are crucial for the nuclear localization of the dengue NS5 protein, which has RNA-dependent RNA polymerase (RdRp) function. A phase 2/3 randomized, double-blind, placebo-controlled trial (NCT02045069) was conducted to study the efficacy of a once-daily dose of Ivermectin 400 μg/kg for 2–3 days in adult dengue patients. Interestingly, the study reported faster NS1 antigenemia clearance upon ivermectin treatment, with no difference in viremia, viral clearance, or any beneficial clinical outcomes, including fever, DHF incidence, hospitalization, pleural effusion, hemoconcentration, or fluid requirements.

Ivermectin Use Against Human Adenoviruses

Human adenoviruses (HAdVs) are ubiquitous and clinically essential pathogens without an effective antiviral treatment. HAdV infections typically cause mild symptoms; however, individuals such as children, those with underlying conditions, and those with compromised immune systems can develop severe disseminated disease. One study found that Ivermectin, an FDA-approved antiparasitic agent, effectively inhibits the replication of several HAdV types in vitro.

Ivermectin Clinical Trials

Ivermectin (Stromectol, Mectizan) has been tested in over 190 clinical trials.

0 min read
Vaccine: 
Availability: 
Global
Generic: 
Ivermectin
Clinical Trial: 
https://clinicaltrials.gov/
Drug Class: 
Antiparasitic Agent
Last Reviewed: 
Tuesday, November 11, 2025 - 10:10
Brand: 
Stromectol
Status: 
Manufacturer Country ID: 
Kosher: 
Yes
Halal: 
Yes
Rate Vaccine: 
gt6GgMo8

Beyfortus (Nirsevimab) RSV Antibody

Beyfortus™ (Nirsevimab) RSV Monoclonal Antibody Clinical Trials, Dosage, Efficacy, Side Effects

Beyfortus™ (Nirsevimab-alip) (MEDI8897) is the first approved single-dose, extended half-life monoclonal antibody (mAb) offering passive immunization to prevent lower respiratory tract infections (LRTI) caused by the respiratory syncytial virus (RSV) in newborns and infants experiencing their first or second RSV season and those with congenital heart disease or chronic lung disease. Beyfortus binds to the prefusion conformation of the RSV fusion protein and was developed in partnership with AstraZeneca and Sanofi using AstraZeneca's technology. In clinical trials, Beyfortus was approximately 90% (95% CI, 75%-96%) protective against RSV-associated hospitalization in infants during their first RSV season.

The concept of using passive immunization strategies to prevent severe RSV illness during infancy is not new. The first proof-of-principle results were obtained from studies conducted in the mid-1980s using animal models of RSV infection. Palivizumab, a humanized RSV-F mouse monoclonal IgG1, was first approved by the U.S. Food and Drug Administration (FDA) in 1998. On July 17, 2023, the FDA Approved Beyfortus. As of May 2025, RSVVaxView reported that nirsevimab coverage among infants <8 months (born since April 1) ranged from 20.5% to 48.2%. Among U.S. territorial and affiliated island jurisdictions, coverage ranged from 0% to 47.8%.

The World Health Organization (WHO) published the preferred product characteristics of monoclonal antibodies for passive immunization against RSV  disease. In September 2024, the WHO SAGE recommended that all countries introduce passive vaccination to prevent severe RSV disease in young infants. In 2025, more than 25 countries are expected to offer Beyfortus. Beyfortus was approved by the European Union (EU) on November 4, 2022. Beyfortus was recommended in AustraliaCanada, China, Europe  (EMEA/H/C/005304), Japan, and France. On July 25, 2024, the Ontario Ministry of Health announced a universal public program with Beyfortus. On May 29, 2025, data show that infant RSV hospitalizations in Spain decreased by 69% following immunization with BEYFORTUS, which targets infants only.

On May 8, 2025, the U.S. CDC MMWR reported a comparison of RSV-associated hospitalization rates among infants aged 0–7 months during 2024–25 with those during pre–pandemic RSV seasons, which were lower by an estimated 28% and 43%, respectively. On June 25, 2025, the CDC's ACIP reviewed a presentation titled "Effectiveness and Impact of RSV Prevention Products in Infants during the 2024–2025 RSV Season." On July 22, 2025, a study, published in PEDIATRICS®, an official journal of the American Academy of Pediatrics, met both of its co-primary endpoints, demonstrating that BEYFORTUS provides 87% reduction in cases of RSV disease across all sites of care among healthy, term babies, born ahead of or during the RSV season, and 98% reduction in hospitalizations of babies with RSV compared to those who did not get BEYFORTUS, per new post-hoc analysis.

Protein Chemical Formula: C6494H10060N1708O2050S46; Protein Average Weight: 146300.0 Da (approximate),  PubChem SID: 384585358, ChEMBL: ChEMBL4297575. CPT codes: 96380, 96381

In March 2017, Sanofi and AstraZeneca announced an agreement to develop and commercialize Beyfortus, with both companies sharing all costs and profits. Sanofi is listed on EURONEXT: SAN and NASDAQ: SNY. AstraZeneca (LSE/STO/Nasdaq: AZN) is a global, science-led biopharmaceutical company. BEYFORTUS - Trademark Details: 90557485

Beyfortus (Nirsevimab) Effectiveness

In November 2025, a study reported that the preventive effect of nirsevimab against RSV infection was observed not only for the first 6 months, but also potentially for up to 12 months after the last dose in children younger than 24 months. On May 29, 2025, Sanofi presented BEYFORTUS® public health advantage of BEYFORTUS®, bolstered by the first real-world comparison of infant vs maternal RSV immunization programs. It's the first real-world findings from the REACH public health impact study, along with updated findings from the HARMONIE Phase 3b clinical trial. REACH Public Health Impact Data: Late-breaking data from REACH show infant RSV hospitalizations were reduced by 69.0% in Spain following Beyfortus-only immunization targeted to all infants and 26.7% in the UK following RSVpreF-only maternal vaccination. The real-world results suggest substantial differences in the public health impact of the respective campaigns. HARMONIE Durability Data: New durability data from HARMONIE show Beyfortus sustained efficacy of 83% through six months, exceeding the typical length of the five-month RSV season. Half of infant RSV hospitalizations occur in babies born before the RSV season begins. These six-month results suggest that older babies can have season-long protection even if they are born and immunized with Beyfortus before the season starts.

In April 2025, a study concluded that the prophylactic administration of Nirsevimab after delivery significantly affects (reduces) the burden of severe acute viral bronchiolitis in pediatric intensive care, while substantially reducing the cost of care. In October 2024, The Lancet published a study (Volume 8, Issue 10) estimating effectiveness against RSV-associated hospitalizations for bronchiolitis at 73% (61–84), corresponding to one hospitalization averted for every 39 (26–54) doses administered. On July 10, 2024, the New England Journal of Medicine reported that in a real-world setting, Beyfortus reduced the risk of infant hospitalization for RSV-associated bronchiolitis by 83%. The effectiveness of therapy against RSV-associated bronchiolitis resulting in critical care was 69.6% (95% CI, 42.9 to 83.8) (27 of 193 case-patients [14.0%] vs. 47 of 146 matched control patients [32.2%]) and against RSV-associated bronchiolitis resulting in ventilatory support was 67.2% (95% CI, 38.6 to 82.5) (27 of 189 case-patients [14.3%] vs. 46 of 151 matched control patients [30.5%]).

On September 11, 2024, a study published by the American Academy of Pediatrics (AAP) concluded that Beyfortus (Nirsevimab) could effectively protect a broad infant population against RSV infection: 63.1% reduction in acute bronchiolitis-related hospital admissions (95% confidence interval [CI], 60.9% to 65.2%), and a 63.1% reduction in pediatric intensive care unit admissions (95% CI, 58.1% to 67.9%). As of September 28, 2024, the AAP recommends Beyfortus for all infants who are not otherwise protected through vaccination during pregnancy. On November 14, 2024, the CDC reported that in Alaska, nirsevimab was 89% effective in preventing RSV-associated hospitalization for infants in their first RSV season and 76% and 88% effective against medically attended illness for children in their first and second seasons, respectively. On November 26, 2024, a study published in The Pediatric Infectious Disease Journal concluded that in immunized infants, RSV-positive bronchiolitis was less frequent and less severe, with a significant reduction in hospitalization length compared to nonimmunized infants, resulting in substantial healthcare cost savings.

On April 29, 2025, a study concluded that the introduction of Nirsevimab was significantly associated with a reduction in hospitalizations and a decrease in the severity of RSV and other respiratory infections. Its use was associated with fewer admissions and a reduced need for intensive care, especially in infants infected with RSV, as well as in those infected with HMPV and adenovirus.

On June 28, 2024, the U.S. CDC vaccine committee reviewed presentations confirming the effectiveness of Beyfortus. On June 5, 2024, the journal Influenza and Other Respiratory Diseases published a Short Communication that estimated nirsevimab's effectiveness at 75.9% (48.5–88.7) in the primary analysis and 80.6% (61.6–90.3) and 80.4% (61.7–89.9) in two sensitivity analyses. During that 2023-2024 RSV season in the U.S., Beyfortus reduced RSV  hospitalizations by 82% (95% CI: 65.6 to 90.2) in infants under six months of age, compared to infants who received no RSV intervention, according to the interim results of an ongoing study published in The Lancet on April 30, 2024. 

Beyfortus (Nirsevimab) Availability

As of 2025, Beyfortus has protected infants in over 20 countries. Beyfortus will be available in the U.S. for the 2025-2026 RSV season in 50 and 100-mg injection doses. The CDC is releasing VFC Beyfortus throughout the RSV season, which is typically first detected in Florida.

In 2023-2024, 40.9% of infants received nirsevimab at a median age of 4 days, according to a study published in JAMA Network Open. Among 42 state and city IIS jurisdictions, the geographic coverage of nirsevimab among infants under 8 months ranged from 2.4% to 22.8% in 2024. Among eight U.S. territorial and affiliated island jurisdictions, coverage ranged from 0.0% to 14.9%.

Beyfortus (Nirsevimab) U.S. FDA

The U.S. FDA Approved Beyfortus in July 2023. The Vaccines and Related Biological Products Advisory Committee (VBPVAC) meeting on December 12, 2024, reviewed presentations on RSV immunization. The FDA's Antimicrobial Drugs Advisory Committee met on June 8, 2023, to discuss the Briefing Document and presentations (2) for the biologics license application (BLA) 761328 submitted by AstraZeneca AB for use with certain neonates, infants, and children. The Committee voted 21-0 in favor of approval. If approved by the FDA, nirsevimab could be available in the U.S. for the 2023/2024 RSV season. On February 5, 2019, the FDA granted Breakthrough Therapy Designation for MEDI8897, an extended half-life RSV F mAb, for the prevention of lower respiratory tract infections (LRTIs) caused by RSV.

Beyfortus (Nirsevimab) U.S. CDC

As of July 2024, the U.S. Centers for Disease Control and Prevention (CDC) recommends passive immunization to protect all infants under 8 months of age and some older babies at increased risk of severe RSV illness. The CDC Advisory Committee on Immunization Practices (ACIP) meeting on June 28, 2024, reviewed various presentations. On August 3, 2023, the ACIP reviewed recommendations, updated nirsevimab EtR, feasibility and implementation plans for monitoring safety and effectiveness in the second season, and Clinical considerations. The ACIP voted unanimously to include Beyfortus in the Vaccines for Children program and to use it in all infants under 8 months.

The CDC Morbidity and Mortality Weekly Report confirmed in March 2024 that the effectiveness was approximately 90% against RSV-associated hospitalizations in infants during their first RSV season. On January 4, 2024, the CDC advised healthcare providers to return to the recommendations (CDCHAN-00499) from the CDC and the Advisory Committee on Immunization Practices (ACIP) regarding the use of nirsevimab in young children. Infants and children who are recommended for nirsevimab should be immunized as soon as possible.

The ACIP previously met on June 22, 2023, and reviewed Clinical Considerations for RSVpreF maternal vaccine and nirsevimab, presented by Jefferson Jones, MD, MPH, FAAP. On February 23, 2023, the ACIP reviewed presentations on the following topics: Introduction, Cost-effectiveness analysis for nirsevimab – CDC model; Cost-effectiveness analysis for nirsevimab – Comparison to manufacturer model; Evidence to Recommendations framework for nirsevimab; Clinical considerations for nirsevimab; Safety and Efficacy of RSV Bivalent PreF Maternal Vaccine; and Workgroup considerations. On October 20, 2022, Dr. C. Felter presented the updated safety and efficacy of Nirsevimab to the ACIP. Previously, the ACIP meeting on June 23, 2022, reviewed Nirsavimab for The Prevention of RSV Disease in All Infants.

Beyfortus (Nirsevimab) Indication

In June 2021, the World Health Organization (WHO) published its preferred product characteristics for long-acting monoclonal antibodies (mAbs) for passive immunization against respiratory syncytial virus (RSV) disease in infants and children (as of June 2022). Nirsevimab is designed to be administered to infants born below eight months of age during the RSV season or children entering their first or second RSV season. Beyfortus is approved for use in infants who remain vulnerable to severe RSV disease through their second RSV season. RSV is a common, contagious virus that causes seasonal epidemics of LRTI, leading to bronchiolitis and pneumonia in infants. The Lancet published results from a study in February 2024 that concluded preterm infants accounted for about 25% of the RSV hospitalization burden in a meta-analysis. On October 26, 2023, the CDC hosted a COCA webinar, "Protecting Infants from RSV," which discussed the fact that approximately 2–3% of young infants are hospitalized for RSV. In Canada, the National Institute of Excellence in Health and Social Services recommends BEYFORTUS for the prevention of RSV LRTD in all neonates and infants aged 8 months or younger.   

Beyfortus (Nirsevimab) Dosage

Beyfortus is injected into the thigh muscle once. The recommended dose is 50 mg for children weighing less than 5 kg and 100 mg for children weighing 5 kg or more.

Beyfortus (Nirsevimab) Mechanism of Action

Nirsevimab is a recombinant human immunoglobulin G1 kappa (IgG1ĸ) long-acting mAb that binds to the prefusion conformation of the RSV F protein. RSV is coated with two types of glycoproteins: the attachment glycoprotein (G protein) and the fusion glycoprotein (F protein). Of these two, only the F protein is essential for the virus to enter cells lining the respiratory tract, making it a desirable target for drug development. The RSV F protein is initially in a metastable prefusion state and undergoes conformational changes upon triggering by an unknown event. These conformational changes lead to a postfusion conformation, in which both the viral and host-cell membranes are together. Nirsevimab binds to a highly conserved RSV prefusion F protein epitope, inhibiting the membrane fusion step in the viral entry process. This allows nirsevimab to neutralize various RSV A and B strains and block cell-to-cell fusion. Nirsevimab has also been modified with a triple amino acid substitution (M257Y/S259T/T261E [YTE]) in the Fc region to extend serum half-life from the typical 21–28 days to approximately 69 days.

Beyfortus (Nirsevimab) CPT Codes

As of October 6, 2023, the American Academy of Pediatrics (AAP) has approved two new Current Procedural Terminology (CPT) codes related to the administration of nirsevimab. One of these codes accounts for the work associated with providing counseling: 96380 Administration of RSV monoclonal antibody, seasonal dose, by intramuscular injection, with counseling by a physician or other qualified healthcare professional; and 96381 Administration of RSV monoclonal antibody, seasonal dose, by intramuscular injection.

Beyfortus Drug Safety-Related Labeling Changes

The price you pay for Beyfortus may depend on your child's dosage and whether you have health insurance. Severe hypersensitivity reactions (02/23/2024, SUPPL-7) have been reported following administration of BEYFORTUS. These reactions included urticaria, dyspnea, cyanosis, and/or hypotonia. Anaphylaxis has been observed with human immunoglobulin G1 monoclonal antibodies. If signs and symptoms of anaphylaxis or other clinically significant hypersensitivity reactions occur, initiate appropriate treatment.

Beyfortus Adverse Reactions Postmarketing Experience

Adverse reactions have been identified during the post-approval use of BEYFORTUS. Because these reactions are reported voluntarily from a population of uncertain size, it is not always possible to estimate their frequency reliably or establish a causal relationship to drug exposure.

Sanofi SP0125

The Phase 3 clinical study evaluating the Sanofi SP0125 (VAD00001) live attenuated vaccine to prevent RSV in toddlers is expected to begin in 2024. SP0125 is administered through the nasal route.

Beyfortus (Nirsevimab) Price

Sanofi launched the BEYFORTUS Reservation Program, which provides critical insight into private healthcare provider demand and prioritizes fulfilling requests through the program. In Canada, each dose costs the province $1000.

On November 16, 2023, the CDC announced the release of Beyfortus to physicians and hospitals through the Federal Vaccines for Children Program and commercial channels. The Ordering Vaccines webpage provides additional guidance on ordering vaccines in the United States. On February 23, 2023, the U.S. CDC reviewed presentations: A cost-effectiveness analysis for nirsevimab—CDC model and a cost-effectiveness analysis for nirsevimab—Comparison to manufacturer model.

Beyfortus Sales

In April 2025, Sanofi announced that Beyfortus sales reached €284 million, driven by increased sales in the Northern Hemisphere, particularly in Germany and Japan. On January 30, 2025, Sanofi announced that Beyfortus sales were €841 million, driven by additional sales in Europe, Germany, and the U.S. The company announced on October 25, 2024, that during Q3, 15.7% sales growth was boosted by earlier-than-anticipated vaccine sales. Beyfortus sales totaled €645 million, driven by early delivery in the U.S. and the rollout in approximately 20 countries in 2024. Beyfortus sales totaled €18 million (USD 19.6 million) in the second quarter of 2024.

Beyfortus (Nirsevimab) News

July 22, 2025 - Ayman Chit, Head of North America Medical, Vaccines, Sanofi, stated in a press release, "These results support BEYFORTUS as a groundbreaking advancement in infant RSV disease prevention. With more than 40 real-world evidence studies to date, this latest study further strengthens the well-established body of data that shows that BEYFORTUS protects against RSV disease to help safeguard the health of all babies, regardless of whether they are born before or during the RSV season."

May 29, 2025 - Thomas Triomphe, Executive Vice President, Vaccines, Sanofi, stated: "The six-month data from HARMONIE show BEYFORTUS' protection exceeded the typical five-month RSV season. This is important because half of infant RSV hospitalizations occur in older babies born before the RSV season begins. These data demonstrating high, sustained efficacy, combined with real-world public health impact data, underscore how BEYFORTUS provides proven protection against the number one cause of lower respiratory tract disease in all infants."

December 9, 2024 - An Original Investigation: Respiratory Syncytial Virus Disease Burden and Nirsevimab Effectiveness in Young Children From 2023-2024 - nirsevimab was effective against RSV-associated hospitalization.

July 25, 2024—The Honourable Sylvia Jones, Ontario Deputy Premier and Minister of Health, commented, "Our government is taking steps to ensure Ontarians of all ages have the tools to be prepared and keep their loved ones safe and healthy before respiratory virus season. Our government is working with our partners to significantly expand Ontario's RSV program to make it easier for families to connect to the care they need, improve health outcomes, and reduce the number of hospitalizations and ICU admissions resulting from RSV."

June 28, 2024: The U.S. CDC vaccine committee reviewed various data presented by Amanda Payne, PhD, MPH, which support the continued use of Beyfortus for most infants during the 2024-2025 RSV season.

April 18, 2024—Delphine Lansac, General Manager of Vaccines Canada at Sanofi, said in a press release, "Parents and physicians who experience the impacts of RSV annually have been waiting for a preventative option that can cover the entire infant population and protect our most vulnerable.

January 2, 2024 - Professor Liu Hanmin, President of West China Second University Hospital, Sichuan University, commented in a press release, "There is currently no specific treatment for RSV disease in infants. This approval (Beyfortus) is crucial to preventing and controlling RSV disease in China."

December 14, 2023: The companies wrote, "We plan to provide approximately 230,000 additional doses—made up of 50mg and 100mg doses—for the U.S. in January. This would bring the first season's immunization rate to nearly 40 percent, significantly surpassing the prior pediatric immunization launch rates. A total of 1.4 million babies will be offered protection against RSV, a 27 percent increase over the initial supply forecast for the season.

August 3, 2023 - Thomas Triomphe, Executive Vice President of Vaccines, Sanofi, commented, "Today, we have turned the corner on the threat of RSV to our youngest, most vulnerable population. The ACIP's unanimous recommendations for the routine use of Beyfortus and its inclusion in the Vaccines for Children program are critical steps toward providing millions of parents in the U.S. with the ability to protect their babies through their first RSV season, when they are most susceptible to severe RSV disease. We appreciate the leadership of the FDA and CDC, as well as the ACIP public health experts, for recognizing and quickly acting on the threat that RSV poses to all infants. "May 12, 23—Thomas Triomphe, Executive Vice President of vaccine lines at Sanofi, stated, 'the HARMONIE data demonstrate the real-world impact  nirsevimab has on pediatric hospitalizations and illustrate its importance for infants, their families, and public health." November 4, 2022 - AstraZeneca and Sanofi announced that the European Commission had approved Beyfortus in the EU to prevent RSV lower respiratory tract disease in newborns and infants during their first RSV season.

May 11, 2022 - AstraZeneca announced results from a prespecified pooled analysis of the pivotal MELODY Phase III and Phase IIb trials showed AstraZeneca and SSanofi'snirsevimab demonstrated an efficacy (relative risk reduction versus placebo) of 79.5% (95% Confidence Interval [CI] 65.9 to 87.7; P<0.0001) against medically attended lower respiratory tract infections (LRTI), such as bronchiolitis or pneumonia, caused by RSV in infants born at term or preterm entering their first RSV season.

March 3, 2022 - Sanofi announced the New England Journal of Medicine published detailed results from a Phase 3 trial evaluating nirsevimab involving healthy infants born at term or late preterm (35 weeks gestational age or more significant) entering their first RSV season and met the primary endpoint, reducing the incidence of medically attended lower respiratory tract infections, such as bronchiolitis or pneumonia, caused by RSV by 74.5% (95% CI 49.6 to 87.1; P<0.001) compared to placebo.

August 11, 2021 - A peer-reviewed study concludes that, based on the mechanism of action of the new generation of antiviral mAbs, such as nirsevimab, which is highly specific in targeting viral antigenic sites, it is unlikely that it could interfere with the immune response to other vaccines.

March 3, 17—Sanofi Pasteur announced Today an agreement with the global biologics research and development arm of AstraZeneca to develop and commercialize MEDI8897, a monoclonal antibody 897, for the prevention of RSV-associated illness in newborns and infants. 

Beyfortus (Nirsevimab) Clinical Trials

Nirsevimab has been tested in several clinical trials. The primary endpoint (prevention of MA RSV was met in both trials: TI—Trial 03 RRR 70.1%, 95% CI (52.3%, 8, and 2%); TI—Trial 04 Primary Cohort RRR 74.9%, 95% CI (50.6%, 87.3%).

The JAMA Network published an Original Investigation on February 17, 2023, suggesting Beyfortus is associated with substantial benefits in preventing RSV infection in children. The peer-reviewed New England Journal of Medicine (NEJM) published a Correspondence on April 5, 2023, Nirsevimab for Prevention of RSV in Term and Late-Preterm Infants, and published a different Correspondence on March 3, 2022: Safety of Nirsevimab for RSV in Infants with Heart or Lung Disease or Prematurity. Found that at day 151, serum levels of nirsevimab were similar in the two cohorts and identical to those reported in the MELODY phase 2/3 clinical trial. The Phase 3 clinical study, Understanding Pre-Exposure Prophylaxis of NOVel Antibodies (SUPERNOVA), was last updated on April 3, 2023.

On May 12, 2023, Sanofi announced new data from the HARMONIE Phase 3b clinical trial show an 83.21% (95% CI 67.77 to 92.04; P<0.001) reduction in hospitalizations due to RSV-related LRTD in infants under 12 months of age who received a single dose of Beyfortus, compared to infants who received no RSV intervention. In addition, the data from HARMONIE also show that nirsevimab reduced the incidence of hospitalizations due to severe RSV-related LRTD (patients whose oxygen level is under 90% and require oxygen supplementation) by 75.71% (95% CI 32.75 to 92.91; P<0.001), and demonstrated a reduction of 58.04% in the incidence of all-cause LRTD hospitalization compared to infants who received no RSV intervention. On December 28, 2023, results (0.3% of those who received nirsevimab were hospitalized for RSV-associated lower respiratory tract infection compared with 1.5% of those who received standard care) from the HARMONIE clinical study indicated that Beyfortus protected infants against hospitalization for RSV-associated LRTD and against very severe RSV-associated lower respiratory tract infection in conditions that approximated real-world settings.

 In the MELODY and Phase 2b trials, the post-dose endpoint for Beyfortus was to reduce the incidence of medically attended lower respiratory tract infections (LRTIs) caused by RSV during the RSV season compared to placebo, achieved with a single dose. The Phase IIb study was a randomized, placebo-controlled trial designed to assess the efficacy of Beyfortus against medically attended lower respiratory tract infections (LRTIs) through post-dose. Healthy preterm infants of 29–35 weeks gestation were randomized (2:1) to receive a 50mg intramuscular injection of Beyfortus or a placebo. The dosing regimen was recommended following further analysis of the Phase IIb data. In the subsequent Phase III study, MELODY applied the recommended dosing regimen.

The MELODY Phase III study was a randomized, placebo-controlled trial conducted in 21 countries. Its purpose was to determine the efficacy of Beyfortus against medically attended lower respiratory tract infections (LRTIs) due to respiratory syncytial virus (RSV), as confirmed by reverse transcriptase polymerase chain reaction testing 150 days after dosing, versus placebo in healthy late preterm and term infants (35 weeks' gestational age or more) entering their first RSV season.

MEDLEY was a Phase II/III, randomized, double-blind, Synagis-controlled trial to assess safety and tolerability for Beyfortus in preterm infants and infants with congenital heart disease and/or chronic lung disease of prematurity (CLD) eligible to receive Synpost-dose9 Between July 2019 and May 2021, approximately 918 infants entering their first RSV season were randomized to receive a single 50mg (in infants weighing <5kg) or 100mg (in infants weighing ≥5kg) intramuscular injection of Beyfortus or Synagis. Safety was assessed by monitoring the occurrence of TEAEs and TESAEs through post-dose. Serum levels of Beyfortus following dosing (on day 151) in this trial were comparable to those observed in the MELODY Phase III trial, indicating similar protection in this population to that in healthy term and late preterm infants is likely. The data was published in the New England Journal of Medicine in March 2022.

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Availability: 
USA, Europe, U.K., Canada, China, Japan
Generic: 
Nirsevimab
Clinical Trial: 
https://www.sanofi.com/en/science-and-innovation/clinical-trials-and-results
Drug Class: 
Monoclonal Antibody
Last Reviewed: 
Sunday, November 9, 2025 - 02:00
Brand: 
Beyfortus
Abbreviation: 
MEDI8897
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FDA First In Class: 
Yes
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