Nov. 7 (UPI) — The incidence of myocarditis — inflammation of the heart muscle — is two to three times higher after a second dose of the Moderna Spikevax COVID-19 vaccine than the Pfizer BioNTech COVID-19 vaccine, a study released on Monday he says. But Moderna tells UPI that the benefits of its vaccine “significantly outweigh” the risks. Men younger than 40 who received the Moderna vaccine were found to have the highest rates of myocarditis, and researchers said the study’s findings support the idea of ​​recommending specific vaccines for certain populations to maximize benefits and minimize side effects. But the scientists stressed that cases of heart inflammation as a serious side effect from any mRNA vaccine are rare overall — also emphasized by the Centers for Disease Control and Prevention, which said it is actively monitoring the situation, and by the manufacturer itself. The most common symptoms of myocarditis are chest pain, fever, fatigue, shortness of breath, and a fast or irregular pulse, says the National Institutes of Health. Inflammation of the heart can lead to serious complications, such as heart failure, shock or death. Moderna, in an emailed statement provided by spokesman Luke Mircea-Willats, said that “its mRNA-1273 has been administered to hundreds of millions of people worldwide and has been shown to be effective against both the original strain of the virus and its major variants. “Regulatory agencies around the world have stated that the benefits of COVID-19 mRNA vaccines significantly outweigh the risk in all age groups. Vaccination against COVID-19 remains a critical tool in addressing the impact of global pandemic.” According to Moderna, myocarditis is a known, though “very rare” risk associated with COVID-19 mRNA vaccines and, “when it occurs, cases are generally mild and resolve after a few days of treatment and rest.” . And, “at the population level,” current evidence shows that the risk of myocarditis after infection with COVID-19 is much higher than after vaccination against COVID-19, Moderna said. Moderna emphasized that the health of patients and ensuring the safety of its vaccines is its top priority, noting that it “shares all adverse event data with regulatory authorities and has a robust pharmacovigilance function, ensuring that any adverse events are recorded and communicated to the regulatory authority according to local authorities. Regulations.” The results of the new study, which was published in the Journal of the American College of Cardiology, are “generally consistent” with the findings of previous studies in the indirect comparison of the safety of the COVID19 mRNA vaccine products, the researchers said in their paper. Epidemiologist Naveed Janjua, lead author of the study, said the findings “have implications for the strategic development of mRNA vaccines, which should also take into account the self-limiting and mild nature of most myocarditis events, the benefits provided by vaccination and the higher effectiveness of the Moderna vaccine against infection and hospitalization [found in prior studies]and the apparent higher risk of myocarditis after infection with COVID-19 than with mRNA vaccination.” Janjua, who is executive director of Data and Analytics Services at the British Columbia Center for Disease Control, made the remarks in a press release. In an accompanying article, Dr. Guy Wittberg, a cardiologist at Rabin Medical Center in Petah Tikva, Israel, wrote that the study is reassuring about the vaccine’s safety, as it provides further data that myocarditis is a very rare adverse event after both vaccines. He also called it “an important step” towards a “personalized and tailored approach to vaccination”. Of the two mRNA COVID-19 vaccines approved for use, more than 52 million doses of Pfizer BioNTech (BNT162b2) and 22 million doses of Moderna Spikevax (mRNA-1273) had been administered by March 20 in Canada, where the study was conducted. , the researchers noted. According to them, few studies have directly compared the safety of the two mRNA COVID-19 vaccines, which the scientists said “differ in important ways that could affect safety.” So the population-based analysis sought to compare the risk of myocarditis, pericarditis, or inflammation of the outer lining of the heart, and myopericarditis — a combination of the two conditions — between the Pfizer and Moderna vaccines for COVID-19. Study participants were 18 years of age or older and had received two primary doses of either the Pfizer or Moderna vaccine in British Columbia, Canada, with the second dose between January 1, 2021, and September 9, 2021. Using data from about 3 million people in the British Columbia COVID-19 Cohort, a population-based cohort study, the researchers looked for a diagnosis of myocarditis, pericarditis, or myopericarditis during hospitalization or an emergency department visit within 21 days of the second dose an mRNA vaccine for COVID-19. Individuals with a history of myocarditis or pericarditis within a year before the second dose of vaccine were excluded. In total, more than 2.2 million second doses of Pfizer and more than 870,000 doses of Moderna were given. Within 21 days of the second dose, there were a total of 59 cases of myocarditis, 21 after Pfizer and 31 after Moderna. and there were a total of 41 cases of pericarditis: 21 after Pfizer and 20 after Moderna. The researchers analyzed the rates per million doses, and the rate was 35.6 cases per million for Moderna and 12.6 cases per million for Pfizer, nearly three times higher. Rates of myocarditis and pericarditis were higher with the Moderna vaccine in both men and women between 18 and 39 years of age, with the highest rates per million in men aged 18-29 years after a second dose of Moderna. According to the researchers, a limitation of the study is that it was observational, which limits the ability to determine causality between vaccination and myocarditis or pericarditis. However, the study was designed to limit the time between the vaccine dose and the diagnosis of myocarditis/pericarditis. Another limitation is that the study was based on hospital and emergency department visit data, so researchers may have missed some less severe cases, the scientists said. The study follows Moderna’s third-quarter earnings report released on Nov. 3. The 2022 sales forecast for the COVID-19 vaccine was cut to between $18 billion and $19 billion in revenue, down from $21 billion.