ASA in Prevention of Ovarian Cancer (STICs and STONEs)

The standard or usual treatment for women with a high risk gene mutation, BRCA1 or BRCA2, is to have risk-reducing surgery to remove the fallopian tubes and ovaries (bilateral salpingo-oophorectomy or bilateral salpingectomy inclusive of fimbria) after they have decided not to have more children naturally.

Acetylsalicylic Acid (ASA) is a safe, well tolerated drug taken by mouth. ASA has been available for over 100 years and has been used mainly to relieve fever and pain, but also as an anti-inflammatory medication in order to reduce inflammation (swelling).

Inclusion criteria

• Previously documented germline BRCA1/2 pathogenic mutation or likely pathogenic variant based on the ACMG 2015 guidelines
• Risk-reducing surgery (bilateral salpingo-oophorectomy or bilateral salpingectomy inclusive of fimbria) scheduled for within 6 months to 2 years after the date of randomization as standard of care, for women who have completed their families
• ECOG performance status 0 or 1
• Age ≥ 18 years old
• Subject is able (i.e. sufficiently literate) and willing to complete the Credibility/Expectancy questionnaire in English or French.
• Subject consent must be appropriately obtained in accordance with applicable local and regulatory requirements. Each subject must sign a consent form prior to enrollment in the trial to document their willingness to participate
• Subjects must be accessible for treatment and follow up. Subjects randomized on this trial must be treated and followed at the participating centre.
• In accordance with CCTG policy, protocol treatment is to begin within 2 working days after subject randomization
• Women of childbearing potential must have agreed to use a highly effective contraceptive method for the duration of the study treatment and for 30 days post last dose of study medication

Exclusion criteria

• Subjects with history of other malignancies, except:

• adequately treated non-melanoma skin cancer;
• curatively treated in-situ cancer of the cervix;
• previously diagnosed (at any point) breast cancer, treated with curative intent; prior chemotherapy is allowed and the last dose must be ≥ 12 months prior to randomization; endocrine therapy for breast cancer is allowed at any time.
• other solid tumours curatively treated with no evidence of disease for > 5 years.
• Subjects who have been treated with any PARP-inhibitors (e.g. olaparib) at any time.
• Subjects with active bleeding or bleeding diathesis.
• Subjects with active peptic ulcer.
• Subjects with renal, hepatic or congestive heart failure.
• Subjects with concurrent use of anti-coagulants and/or anti-platelet agents.
• Subjects with prior bilateral salpingectomy.
• Subjects with history of chronic daily use of ASA or NSAIDs.
• Subjects with intolerance of ASA including subjects with a history of asthma induced by salicylates or substances with a similar action, notably non-steroidal-anti-inflammatory drugs.
• Ongoing or planned pregnancy.
• Subjects who are breastfeeding.