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By Nancy Lapid
March 31 (Reuters) - The following is a roundup of some of
the latest scientific studies on the novel coronavirus and
efforts to find treatments and vaccines for COVID-19, the
illness caused by the virus.
Pfizer/BioNTech vaccine safe, effective in adolescents
Pfizer Inc and BioNTech SE said on
Wednesday their two-shot COVID-19 vaccine is safe and effective
and produces robust antibody responses in 12 to 15-year-olds.
The findings will likely allow use of the vaccine in that group
before the next school year, Pfizer Chief Executive Albert
Bourla said in a statement. Currently, the vaccine is authorized
for use starting at age 16. In the new study, involving 2,260
adolescents aged 12 to 15, there were 18 cases of COVID-19 in
volunteers who got a placebo and none in those who received the
vaccine, resulting in 100% efficacy in preventing COVID-19, the
companies said without releasing a formal report. Side effects
were in line with the generally mild ones seen in adults, such
as injection-site pain, headaches, fever and fatigue, according
to the announcement. In a subset of youngsters, researchers
measured the level of virus-neutralizing antibodies a month
after the second dose and found it comparable to that in 16- to
25-year-olds in adult trials. Other companies are also testing,
or planning to test, their vaccines in children. Moderna Inc
is studying its COVID-19 vaccine in adolescents aged 12
to 17 and in children aged six months to 11 years. (https://reut.rs/31xg6HA)
Arthritis drug reduces potency of first vaccine dose
The first dose of the COVID-19 vaccines from Pfizer/BioNTech
and from AstraZeneca Plc produces only weak immune
responses in patients being treated with the widely-used
rheumatoid arthritis drug infliximab, researchers have found.
Infliximab, sold by Johnson & Johnson under the brand
name Remicade and available in biosimilar versions, is also
approved to treat a range of other autoimmune disorders
including plaque psoriasis and ulcerative colitis. In a study of
865 patients receiving regular infusions of infliximab,
researchers observed "poor antibody responses" after a single
dose of either of the vaccines, which exposes these patients to
a potential increased risk of coronavirus infection, according
to a paper posted on Monday on medRxiv ahead of peer review. The
responses improved after the second dose, which suggests
patients on infliximab should not delay their second shot, the
researchers said. "Until patients receive a second vaccine dose,
they should consider that they are not protected from SARS-CoV-2
infection and continue to practice enhanced physical distancing
and shielding if appropriate," they advised. Even after two
doses, they found that a small subset of patients failed to
mount an antibody response. The researchers added that they
suspect their findings will apply to other drugs in the class
known as TNF inhibitors, including Abbvie's Humira and
Amgen's Enbrel, two of the world's top selling
medicines. "Antibody testing and adapted vaccine schedules
should be considered to protect these at-risk patients," the
researchers said. (https://bit.ly/31xCKzC)
COVID-19 was third leading cause of U.S. deaths in 2020
COVID-19 was the primary or contributing cause of 378,048
U.S. deaths last year, making it the third leading cause of
death in the United States in 2020 after heart disease and
cancer, according to data released on Wednesday by the U.S.
Centers for Disease Control and Prevention (CDC). In one study,
which used preliminary data for 2020, researchers found the
overall U.S. mortality rate increased for the first time since
2017, by nearly 16%, with COVID-19 accounting for an increase of
11.3%. The highest overall numbers of deaths occurred during the
weeks ending April 11 (78,917) and December 26 (80,656). The
COVID-19 death rate was highest among Hispanics, followed by
Black non-Hispanics; it was lowest among children aged 5 to 14,
and highest among people over age 85. In a second study,
researchers found that death certificate data for 2020 collected
through February 2021 largely confirm the preliminary data in
the other report. The CDC pointed out that limited availability
of testing for the coronavirus at the beginning of the pandemic
might have resulted in an underestimation of COVID-19-associated
deaths. (https://bit.ly/31yLnK6; https://bit.ly/3mfrAZR)
High-risk U.S. adults may not consistently wear masks
Most U.S. adults with chronic medical conditions know they
face higher odds of severe COVID-19 but that does not mean they
avoid high-risk behaviors, survey data suggest. In late 2020,
researchers asked nearly 6,000 participants in the Understanding
America Study about their perceived risks from the new
coronavirus, and their mask-wearing behavior. They also asked if
participants had been diagnosed with a variety of known risk
factors - chronic lung disease, kidney disease, heart disease,
cancer, autoimmune disorders, diabetes, asthma, high blood
pressure, or obesity. All of those conditions, except for high
blood pressure and kidney disease, were linked with perceptions
of higher risks for COVID-19 complications and death among
respondents. Compared to people with none of these medical
conditions, those with three or more had engaged in about 10%
fewer activities in the past week. But only when visiting a
grocery store or pharmacy were participants with three or more
medical risk factors more likely to always wear a mask than
those with no conditions. During other common activities,
including visiting with friends, the majority of adults,
including the highly susceptible, did not consistently wear
masks, the researchers reported on Wednesday in JAMA Network
Open. They "understood their risks were higher, but consistent
mask wearing remained low," the researchers said. (https://bit.ly/3rzVVTT)
Open https://tmsnrt.rs/3c7R3Bl in an external browser for
a Reuters graphic on vaccines in development.
(Reporting by Nancy Lapid, Julie Steenhuysen and Vishwadha
Chander; Editing by Bill Berkrot)
