Purpose: Balstilimab (antiprogrammed death-1) and zalifrelimab (anticytotoxic T-lymphocyte-associated antigen-4) are two new checkpoint inhibitors emerging as promising investigational agents for the treatment of advanced cervical cancer. This phase II trial (ClinicalTrials.gov identifier: NCT03495882) evaluated the combination of balstilimab plus zalifrelimab in patients with recurrent and/or metastatic cervical cancer who relapsed after prior platinum-based therapy., Patients and Methods: Patients were intravenously dosed with balstilimab 3 mg/kg once every 2 weeks and zalifrelimab 1 mg/kg once every 6 weeks, for up to 24 months. The primary end point was objective response rate (ORR, RECIST version 1.1, assessed by independent central review). Secondary end points included duration of response, safety and tolerability, and survival., Results: In total, 155 women (median age, 50 years [range, 24-76 years]) were enrolled and treated with balstilimab plus zalifrelimab; 125 patients had measurable disease at baseline and one prior line of platinum-based therapy in the advanced setting, and these patients constituted the efficacy-evaluable population. The median follow-up was 21 months. The confirmed ORR was 25.6% (95% CI, 18.8 to 33.9), including 10 complete responders and 22 partial responders, with median duration of response not reached (86.5%, 75.5%, and 64.2% at 6, 9, and 12 months, respectively). The ORRs were 32.8% and 9.1% in patients with programmed death ligand-1-positive and programmed death ligand-1-negative tumors, respectively. For patients with squamous cell carcinoma, the ORR was 32.6%. The overall disease control rate was 52% (95% CI, 43.3 to 60.6). Hypothyroidism (14.2%) and hyperthyroidism (7.1%) were the most common immune-mediated adverse events., Conclusion: Promising and durable clinical activity, with favorable tolerability, was seen in this largest trial to date evaluating dual programmed death-1/cytotoxic T-lymphocyte-associated antigen-4 blockade in patients with recurrent and/or metastatic cervical cancer. Further investigation of the balstilimab and zalifrelimab combination in this setting is continuing., Competing Interests: David M. O'MalleyConsulting or Advisory Role: Janssen Oncology, AstraZeneca, Clovis Oncology, Tesaro, Novocure, AbbVie, Genentech/Roche, OncoQuest, Immunogen, GOG Foundation, Translational Genomics Research Institute, Agenus, Marker Therapeutics, Eisai, Genelux, Iovance Biotherapeutics, Ambry Genetics, Tarveda Therapeutics, Leap Therapeutics, Myriad Genetics, GlaxoSmithKline, Regeneron, Sorrento Therapeutics, Rubius Therapeutics, Elevar Therapeutics¸ Novartis, Seattle Genetics, BBI Healthcare, Arquer Diagnostics¸ Toray Medical, Takeda, InxMed, Celsion, Roche Diagnostics MSAResearch Funding: Amgen (Inst), AstraZeneca (Inst), Genentech/Roche (Inst), Regeneron (Inst), Immunogen (Inst), Janssen Research & Development (Inst), Clovis Oncology (Inst), EMD Serono (Inst), Ergomed (Inst), Ajinomoto (Inst), Immunogen (Inst), Cerulean Pharma (Inst), PharmaMar (Inst), Array BioPharma (Inst), Bristol Myers Squibb (Inst), Agenus (Inst), Tesaro (Inst), TRACON Pharma (Inst), Genmab (Inst), Seattle Genetics (Inst), Iovance Biotherapeutics (Inst), Merck (Inst), AbbVie/Stemcentrx (Inst), AbbVie (Inst), Mersana (Inst), Eisai (Inst), BBI Healthcare (Inst), Sumitomo Dainippon Pharma Oncology (Inst), Bradley J. MonkLeadership: US OncologyHonoraria: AbbVie, Advaxis, Agenus, Akeso Biopharma, Amgen, Aravive, AstraZeneca, Asymmetric Therapeutics, Boston Biomedical, ChemoID, Clovis Oncology, Deciphera Pharmaceuticals, Eisai¸ Geistlich Pharma, Genmab/Seattle Genetics, ImmunoGen, Immunomedics, Incyte, Iovance Biotherapeutics, Laekna Health Care, Mersana, Merck, Myriad Pharmaceuticals, NuCana, OncoMed, OncoQuest, OncoSec, Perthera, Pfizer, Puma Biotechnology, Regeneron, Roche/Genentech, Senti Biosciences, Takeda, Tarveda Therapeutics, Tesaro/GSK, Vavotar Life Sciences, Vascular Biogenics, Vigeo Therapeutics, GOG Foundation, Starton Therapeutics, Elevar Therapeutics, Novocure, Iovance Biotherapeutics, Gradalis, Karyopharm TherapeuticsConsulting or Advisory Role: AbbVie, Advaxis, Agenus, Akeso Biopharma, Amgen, Aravive, AstraZeneca, Asymmetric Therapeutics, Boston Biomedical, ChemoID, Clovis Oncology, Deciphera Pharmaceuticals, Eisai¸ Geistlich Pharma, Genmab/Seattle Genetics, GOG Foundation, ImmunoGen, Immunomedics, Iovance Biotherapeutics, Laekna Health Care, Mersana, Merck, Myriad Pharmaceuticals, NuCana, OncoMed, OncoQuest, OncoSec, Perthera, Pfizer, Puma Biotechnology, Regeneron, Roche/Genentech, Senti Biosciences, Takeda, Tarveda Therapeutics, Tesaro/GSK, Vavotar Life Sciences, Vascular Biogenics, Vigeo Therapeutics, Gradalis, Karyopharm Therapeutics, Sorrento Therapeutics, Novocure, ChemocareSpeakers' Bureau: Roche/Genentech, AstraZeneca, Clovis Oncology, Eisai, Tesaro/GSK, MerckResearch Funding: Amgen (Inst), Genentech (Inst), Lilly (Inst), Janssen (Inst), Array BioPharma (Inst), Tesaro (Inst), Morphotek (Inst), Pfizer (Inst), Advaxis (Inst), AstraZeneca (Inst), ImmunoGen (Inst), Regeneron (Inst), NuCana (Inst) Marilyn HuangConsulting or Advisory Role: Tesaro, Seattle Genetics, Aptitude Health, Agenus, Cooper Surgical, touchExpert opinionsResearch Funding: Merck (Inst) Tarek M. MeniawyHonoraria: AstraZeneca/MedImmuneConsulting or Advisory Role: AstraZeneca/MedImmune, Novartis, GlaxoSmithKline, BMSResearch Funding: Bristol Myers Squibb (Inst), BeiGene (Inst), Incyte (Inst), AstraZeneca/MedImmune (Inst), Regeneron (Inst), Bayer (Inst), Merck Serono (Inst), Roche/Genentech (Inst)Travel, Accommodations, Expenses: BMS Waldo Ortuzar FeliuEmployment: AgenusStock and Other Ownership Interests: AgenusTravel, Accommodations, Expenses: Agenus Marek AncukiewiczEmployment: Agenus, LFB Biotechnologies, Boston Scientific (I)Stock and Other Ownership Interests: Agenus, Boston Scientific (I) Iwona LugowskaHonoraria: Roche, Agen7s, MSD, AmgenResearch Funding: Roche (Inst), Novartis (Inst)Travel, Accommodations, Expenses: Roche/GenentechNo other potential conflicts of interest were reported.