How long does PARP inhibitor therapy take to work for ovarian cancer?

PARP inhibitors interfere with repair processes that some cancer cells rely on. They are usually taken repeatedly according to the prescribed schedule, so the goal is ongoing control rather than a single moment when treatment switches on.

Your oncologist may combine symptom review, examination, blood tests and imaging when deciding whether the treatment is helping. A change in symptoms alone may not show the full picture, and stable findings can also be meaningful. The timing of scans depends on your treatment plan and the features of your ovarian cancer.

Take each dose as directed and do not double a missed dose unless your team tells you to. Report nausea, vomiting, unusual tiredness, breathlessness, fever, bruising or signs of infection. Your team may check blood counts and organ function and may pause or alter treatment if side effects need attention.

Contact your cancer team promptly for fever, chills, persistent vomiting, severe weakness, unusual bleeding, worsening breathlessness or chest pain. Ask for urgent help if symptoms are severe, sudden or rapidly worsening.

Ask when your first response review is planned, which tests will be used, what a useful response would look like, and what to do after a missed dose.