Atezolizumab in this study is expected to have a positive benefit-risk profile for the treatment of patients with platinum-sensitive relapse of ovarian cancer. Of interest, atezolizumab is being investigated also in combination with platinum-based doublet chemotherapy in second line (2L)/ third line (3L) platinum-sensitive recurrent ovarian cancer patients in ATALANTE (NCT02891824), which also includes bevacizumab in the combination. The study is proceeding as expected after \>100 patients enrolled and under independent Data Monitoring Committee (IDMC) supervision. Platinum-containing therapy is considered the treatment of choice for patients with platinum-sensitive relapse. However the duration of response and the prolongation of the progression free interval with chemotherapy are usually brief, among other because these chemotherapy regimens cannot be continued until progression as they are associated with neurological, renal and hematological toxicity and cannot generally be tolerated for more than about 6 to 9 cycles. Niraparib received FDA approval in March 2017 as maintenance treatment of adult patients with recurrent epithelial ovarian, fallopian tube or primary peritoneal cancer who are in complete or partial response to platinum-based chemotherapy. Recently, the European Medicines Agency (EMA) has also approved niraparib as maintenance monotherapy. Despite the progress brought about by niraparib, there is a need for a more effective treatment to extend the progression free interval in this patient population. The combination with immune checkpoint inhibitors such as anti-death protein 1 (anti-PD1) or anti-death protein ligand 1 (anti-PD-L1) has a compelling rationale to this aim, especially under the light of the emerging clinical data of this combination. The use of atezolizumab concurrent to platinum-containing chemotherapy followed by niraparib as maintenance therapy after completion of chemotherapy, as per normal clinical practice, may provide further benefit to patients in terms of prolonging the progression free interval and increasing the interval between lines of chemotherapy, hence delaying further hospitalization and the cumulative toxicities associated with chemotherapy. Additionally, preliminary studies with atezolizumab suggest an acceptable tolerability profile for long term clinical use in recurrent ovarian cancer patients and other indications.