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* EMA assessed 8 cases of serious clots in the United States
* Says overall benefits outweigh any risks
* Cases occurred in adults under 60, most of them women
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By Pushkala Aripaka, Anthony Deutsch and John Miller
April 20 (Reuters) - Europe's drug regulator has found a
possible link between Johnson & Johnson's COVID-19
vaccine and rare blood clotting issues in adults who received
doses in the United States, but backed its overall benefits
against any risks.
The European Medicines Agency (EMA) said on Tuesday its
safety committee had concluded that a warning about unusual
blood clots with low platelets must be added to the vaccine's
labels, just as has also been required of rival shot maker
AstraZeneca.
The questions over the J&J shot have dealt a further blow to
the EU's vaccination programme, which has lagged rollouts in
Britain and the United States due to supply delays as well as
safety concerns. Rising infections caused by more infectious
variants have forced France and others to reimpose lockdowns.
The review of a handful of cases prompted a pause in the
rollout of the J&J vaccine in Europe and the United States last
week, the latest setback to efforts to tackle the pandemic,
which has killed more than 3.1 million and infected 142.1
million worldwide.
While the regulator said it considers the vaccine safe, it
was up to the European Union's member states to decide how to
use it, taking a similar stance to that with AstraZeneca.
"I have to stress again (the cases) are very rare and in the
vast majority of cases these vaccines are going to prevent death
and hospitalisation from COVID-19," EMA executive Director Emer
Cooke said in a briefing.
"We have to balance the benefits of the vaccine with the
risks."
Several nations have suspended or limited the use of
AstraZeneca's vaccine over possible blood clots. (https://bit.ly/3xckNFu)
The EMA examined eight cases of clotting that occurred in
U.S. adults under 60 years, mostly women, within three weeks of
vaccination with J&J's single shot. The cases were reported out
of more than 7 million doses administered in the United States
as of April 13.
If treated early, health care professionals can help people
in their recovery and avoid further complications, Sabine
Straus, chair of EMA's safety committee, told the briefing.
EXTREMELY RARE CLOTTING
With both the AstraZeneca and J&J vaccines, the reports
involve extremely rare clotting, mainly a type of blood clot
called cerebral venous sinus thrombosis (CVST), which was seen
in combination with low levels of blood platelets, called
thrombocytopenia.
J&J has said it is working closely with regulators and noted
that no clear causal relationship had been established between
the clotting cases and its shot.
The EU watchdog said most clots had occurred in the brain
and abdomen, as was the case with AstraZeneca's shot, Vaxzevria,
which is also being studied for similar problems.
"One plausible explanation for the combination of blood
clots and low blood platelets is an immune response, leading to
a condition similar to one seen sometimes in patients treated
with heparin," the EMA said.
There have been more than 300 cases worldwide of rare blood
clotting incidents combined with low platelet counts after use
of all COVID-19 vaccines, it added.
Some scientists say the similar design of the AstraZeneca
and J&J shots may explain a possible link with clotting. Both
vaccines are based on a technology that uses a modified version
of adenoviruses, which cause the common cold, as vectors to
ferry instructions to human cells.
The similar side-effects suggest the inactivated adenovirus
may be causing the problems, said Jonathan Ball, professor of
molecular virology at Britain's University of Nottingham.
"It's important to remember though, that in most people the
benefits of these vaccines far outweigh the risks - these are
incredibly rare potential side-effects," he said.
U.S. authorities will meet on Friday to discuss whether to
resume using the J&J vaccine.
J&J, which recorded $100 million in COVID-19 vaccine sales,
has delayed rolling out the vaccine to Europe, but said on
Tuesday it was prepared to resume the deployment. It has said it
aims to deliver 55 million doses to the EU, as contracted, by
the end of June.
J&J's vaccine, developed by its Janssen unit, is one of four
COVID-19 vaccines authorised for use in Europe.
(Additional reporting by Toby Sterling in Amsterdam, Ludwig
Burger in Frankfrut, Julie Steenhuysen in Chicago and Kate
Kelland in London; Writing by Josephine Mason; Editing by Gareth
Jones)
