Nektar presents preclinical study findings for etirinotecan pegol combination Nektar Therapeutics announced results of a study investigating the preclinical anti-tumor activity and tolerability of etirinotecan pegol in combination with the PARP inhibitor rucaparib in a BRCA1-deficient MX-1 breast tumor model. The preclinical study results demonstrated that all dose combinations of NKTR-102 and rucaparib were well-tolerated, synergistic, and led to 100% prolonged survival in this tumor model. These data were presented during the Symposium on Molecular Targets and Cancer Therapeutics in Barcelona, Spain. NKTR-102 and rucaparib in combination exhibited marked synergy, demonstrated by durable complete responses, even at the lowest doses of both agents dosed in combination. The combination of NKTR-102 and rucaparib was tolerated at all dose levels. Doses used in this study provide exposures of NKTR-102 and rucaparib that are achievable clinically, underscoring the translational relevance of these results. Combination studies of NKTR-102 and rucaparib are ongoing in patient-derived xenograft models in collaboration with Professor Paul Haluska at Mayo Clinic and Clovis Oncology.