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By Ludwig Burger
BARCELONA, Sept 30 (Reuters) - AstraZeneca presented
results on Monday for a trial of its Lynparza drug against
prostate cancer, which it hopes could lead to wider regulatory
approval for the treatment for use against more forms of the
disease.
The British drugmaker, together with development partner
Merck & Co, said Lynparza was shown to delay disease
progression in an aggressive and difficult-to-treat type of
prostate cancer by a median 3.8 months in the group most
sensitive to the treatment.
The data, presented at the annual conference of the European
Society for Medical Oncology (ESMO) in Barcelona, adds to
further promising results presented on Saturday at the
conference that may lead to wider use in women suffering from
ovarian cancer.
In the prostate cancer study researchers gave Lynparza to
men with metastatic disease that had worsened despite at least
two forms of hormone therapy, and compared time to progression
with a reference group of patients on standard hormone therapy.
Many cancer cells have a limited ability to make DNA repairs
during cell division, as healthy cells would. This feature makes
tumours genetically volatile and helps them develop resistance
to treatment over time.
Lynparza, and other drugs in the drug class of PARP
inhibitors that it belongs to, are designed to block what is
left of the DNA repair mechanism so cancer cells fail to
replicate.
The trial was restricted to patients that were found to have
a range of genetic mutations that hamper DNA repairs, grouped
together under the term homologous recombination deficiency
(HRD).
Depending on the extent of HRD, Lynparza delayed disease
progression - which in this patient group often means painful
bone metastases - by between 2.3 to 3.8 months.
AstraZeneca said it would seek approval for wider use with
health regulators.
Analysts see AstraZeneca and Merck's Lynparza leading the
PARP inhibitor class with an average sales estimate of $3.1
billion for 2023. Rival GlaxoSmithKline's Zejula is
expected to achieve about 870 million pounds ($1.1 billion) in
revenue that year.
Other approved PARP inhibitors, Pfizer's Talzenna
and Clovis Oncology's Rubraca, are seen as further
behind in terms of future revenue prospects. Abbvie is
testing an experimental compound called veliparib.
($1 = 0.8039 pounds)
(Reporting by Ludwig Burger; Editing by Jan Harvey)
