LONDON, Nov 4 (Reuters) - AstraZeneca's new cancer drug olaparib, which won a green light from European regulators last month for inherited ovarian cancer, could also be used much more widely to treat prostate cancer, according to a leading oncologist.
Johann de Bono, professor of experimental cancer therapeutics at the Institute of Cancer Research in London, told a conference on Tuesday the drug had produced "encouraging" preliminary results in clinical tests against prostate cancer.
Olaparib works by blocking an enzyme involved in cell repair and is designed for patients with hereditary BRCA gene mutations, which are also found in breast and gastric cancer.
While AstraZeneca believes the drug has the potential to sell $2 billion a year, the company has so far only talked about its promise in ovarian, breast and gastric cancer.
However, de Bono told the National Cancer Research Institute that olaparib might also work in patients who have not inherited BRCA mutations but do carry mutations to DNA repair genes within their tumours.
To test the theory, de Bono and colleagues have assessed olaparib in advanced prostate cancer tests, including a mid-stage Phase II clinical trial, the first part of which has now closed.
"Although PARP inhibitors like olaparib have generally been trialled in women with inherited BRCA mutations, these exciting new trials could give them a whole other lease of life in advanced prostate cancer and other tumours with DNA repair mutations," de Bono said.
"It is too early to say whether they will prove to be beneficial in prostate cancer but the initial results from our preliminary trials have been encouraging."
Olaparib is on track to become the first poly ADP-ribose polymerase (PARP) inhibitor to reach the market, following the European recommendation. AstraZeneca plans to market it under the brand name Lynparza.
Cancer medicine is a core focus for AstraZeneca and central to its claims to have a strong independent future, after fending off a $118 billion takeover bid from Pfizer in May.
The British drugmaker earlier on Tuesday moved to strengthen its oncology business with three new collaborations that will extend its reach in the fast-growing and promising field of cancer immunotherapy.
(Reporting by Ben Hirschler. Editing by Jane Merriman)