Parp inhibitor drugs have changed the natural history of ovarian cancer and continue to do so. We are talking about one of the most aggressive female neoplasms, which occurs at an advanced stage in 80% of cases and which, even when discovered at an early stage, often causes relapses. Now, the independent PRIME study shows that, in patients with stage III / IV ovarian cancer, individually administered Parp-inhibitor niraparib is able to triple progression-free survival compared to placebo. In fact, in women who received the drug, this survival was over two years, while in those who had been treated with placebo the recovery of the disease occurred after just over 8 months. These data equate to a 55% reduction in the chance of the cancer returning or dying.
Benefits even without mutations
The study was conducted in China and confirms the results of the PRIMA trial, which led to the drug’s registration (compared to PRIMA, the PRIME study included stage III patients who had no residual disease after surgery). In Italy, niraparib is in fact approved for first-line maintenance treatment and in monotherapy, in patients with complete or partial response to chemotherapy and regardless of the presence of mutations. “An important finding is that in all subgroups of patients – with mutations in the BRCA genes, with homologous recombination deficiency or without alterations of these genes – a statistically significant benefit in terms of progression-free interval was observed”, he points out. Giorgio Valabregaof the Department of Oncology of the University of Turin and of Oncology of the Mauriziano Umberto I Hospital in the Savoy city.
The advantage of the personalized dose
In the trial – whose data were presented at the Annual Meeting on Women’s Cancer of the Society of Gynecologic Oncology – the authors administered an individualized dose of the drug from the beginning, based on body weight and platelet count, precisely to improve the safety profile. And the data confirm the improvement: only 6.7% of patients treated with the drug (5.4% in the placebo arm, for comparison) permanently discontinued treatment due to adverse events. This is the lowest percentage among those reported in Phase III studies with Parp inhibitors in ovarian cancer. “PRIME definitively confirms that the dosage of niraparib must be individualized for each individual patient, even in the first line, as already partially suggested by the PRIMA study – continues Valabrega – In this way it is possible to greatly reduce the side effects, without compromising the ‘efficacy of the drug “