Olaparib causes anti-tumour activity in ovarian breast cancer sufferers carrying the BRCA1 or BRCA2 gene mutation, two proof-of-concept trials have found.
The research suggests that therapy for ovarian, breast and potentially other cancers can be targeted on shared genetic defects and not the organ of origin.
One in 10 women with ovarian cancer and one in 20 women with breast cancer carry a mutation in the genes BRCA1 or BRCA2, which creates a high risk of development of the cancers, the articles published online in The Lancet report.
Andrew Tutt, from the Breakthrough Breast Cancer Research Unit at King's College London School of Medicine, led an international team that carried out two proof-of-concept trials to analyse the efficacy and safety of olaparib for patients with the gene mutations.
Findings indicated better treatment response with the higher dose of olaparib compared with lower dose in both trials. In both the ovarian and breast cancer studies, olaparib was generally well tolerated, with most adverse events being low grade.
In the report on ovarian cancer, first author M William Audeh from the Samuel Oschin Cancer Institute and colleagues said: "The results of this phase 2 study show that the oral PARP inhibitor olaparib, given as monotherapy at a dose of 400 mg twice daily, has antitumour activity in heavily pretreated carriers of the BRCA1 or BRCA2 mutation who have recurrent ovarian cancer."