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(Adds detail on Calquence, background)
By Aakash B
April 14 (Reuters) - AstraZeneca Plc said on Tuesday
it would start a clinical trial of its cancer drug Calquence to
assess its potential to control the exaggerated immune system
response associated with COVID-19 infection in severely ill
patients.
Calquence (acalabrutinib) belongs to a class of drugs called
Bruton's tyrosine kinase (BTK) inhibitors which can suppress
autoimmune diseases. The drug, which is currently used to treat
certain types of blood cancers, has already been approved for
the treatment of adult patients with chronic lymphocytic
leukaemia in the U.S. and several other countries.
Calquence competes with AbbVie Inc and Johnson &
Johnson's established treatment Imbruvica as a treatment
for chronic lymphocytic leukemia, one of the most common types
of leukemia in adults.
The British drugmaker's shares rose as much as 7.3% to 7642
pence by 0855 BST.
AstraZeneca's announcement comes as drugmakers are having to
pause clinical trials for other disease areas as they focus on
testing potential treatments for the fast-spreading coronavirus.
Patients with severe symptoms including pneumonia are
believed to suffer from an over reaction of the immune system
known as cytokine storm and AstraZeneca aims to test whether
Calquence, which suppresses certain elements of the immune
system, can help control this immune response.
"Given the well documented role of the protein BTK in
regulating inflammation, it is possible that inhibiting BTK with
acalabrutinib could provide clinical benefit in patients with
advanced COVID-19 lung disease," said Louis Staudt, chief of the
lymphoid malignancies branch at the National Cancer Institute.
The trial will evaluate the effectiveness and safety of
adding the drug to best supportive care to reduce mortality and
the need for assisted ventilation in patients with
life-threatening COVID-19 symptoms, the drugmaker said.
It is expected to open for enrolment in the coming days in
the U.S. and several countries in Europe, AstraZeneca said.
Earlier this month, AstraZeneca and its domestic rival
GlaxoSmithKline PLC agreed to set up a testing
laboratory to aid in COVID-19 testing with Cambridge University.
(Reporting by Aakash Jagadeesh Babu in Bengaluru and Ludwig
Burger; Editing by Patrick Graham, Sherry Jacob-Phillips and
Mike Harrison)
