Background Olaparib and Niraparib are oral antineoplastics used for the maintenance treatment of high-grade ovarian cancer, relapsed, complete or partial response to platinum-based chemotherapy. Olaparib is indicated for patients with BRCA +mutation and marketed in our country: Niraparib is independent of the mutation and it is used in compassionate use.

Purpose Comparing the safety profile of Niraparib and Olaparib, in the everyday clinical practice of a tertiary hospital.

Material and methods Descriptive, transversal, retrospective research of all patients treated with Niraparib or Olaparib until September 2018. Data: clinical and pharmacological history (Farmatools). Variables: age, date of beginning, end and/or reintroduction of treatment, reason for suspension, initial dose, dose reduction, current dose, days of treatment and adverse effects. Analysis: SPSS Statistics.

Results Eight patients with Olaparib and 11 with Niraparib, with an average age of 65 (50–86) and 61 (48–73) respectively. The median of treatment with Olaparib was 455 (25–1264) and with Niraparib 35 (2–91).

Olaparib: seven (87.5%) patients started with 400 mg and one (12.5%) with 200 mg. Three (50%) needed dose reduction and all had started with 400 mg. In two patients the treatment was suspended due to death and progression respectively. Six (75%) continued in treatment (three with 400 mg, two 200 mg and one 100 mg). In one (16.7%) of them the treatment was temporarily suspended due to decreased haemoglobin and three (37.5%) had adverse effects (nausea, vomiting, stomach pain) without interruption of treatment.

Niraparib: four (36.4%) patients started with 300 mg and seven (63.6%) 200 mg. Five (45.5%) patients needed dose reduction, two with initial dose 300 mg and three 200 mg: three of them continued (one of 300 mg and two of 200 mg initial dose). In five (45.5%) patients, treatment was discontinued, two (40%) due to adverse effects (neutropaenia, thrombocytopaenia and increased creatinine respectively) and three due to progression (60%), in addition temporarily suspending it due to neutropaenia. Six continued (three with 200 mg and three with 100 mg) and three of them had to temporarily interrupt it due to thrombocytopaenia.

Conclusion In both treatments, the haematological adverse effects are more severe, frequent and worse tolerated in the case of Niraparib than Olaparib. In addition, greater discontinuity of treatment is observed in patients with Niraparib.

References and/or acknowledgements No conflict of interest.