CX-072 (pacmilimab), a Probody PD-L1 inhibitor, in combination with ipilimumab in patients with advanced solid tumors (PROCLAIM-CX-072): a first-in-human, dose-finding study
Authors
Sanborn, R. E.Hamid, O.
de Vries, E. G.
Ott, P. A.
Garcia-Corbacho, J.
Boni, V.
Bendell, J.
Autio, K. A.
Cho, D. C.
Plummer, R.
Stroh, M.
Lu, L
Thistlethwaite, Fiona C
Affiliation
Department of Medical Oncology, Earle A. Chiles Research Institute, Providence Cancer Institute, Portland, Oregon, USAIssue Date
2021
Metadata
Show full item recordAbstract
Background: Probody® therapeutics are antibody prodrugs designed to be activated by tumor-associated proteases. This conditional activation restricts antibody binding to the tumor microenvironment, thereby minimizing 'off-tumor' toxicity. Here, we report the phase 1 data from the first-in-human study of CX-072 (pacmilimab), a Probody immune checkpoint inhibitor directed against programmed death-ligand 1 (PD-L1), in combination with the anti-cytotoxic T-lymphocyte-associated protein 4 (anti-CTLA-4) antibody ipilimumab. Methods: Adults (n=27) with advanced solid tumors (naive to PD-L1/programmed cell death protein 1 or CTLA-4 inhibitors) were enrolled in the phase 1 combination therapy dose-escalation portion of this multicenter, open-label, phase 1/2 study (NCT03013491). Dose-escalation pacmilimab/ipilimumab followed a standard 3+3 design and continued until the maximum tolerated dose (MTD) was determined. Pacmilimab+ipilimumab was administered intravenously every 3 weeks for four cycles, followed by pacmilimab administered every 2 weeks as monotherapy. The primary objective was identification of dose-limiting toxicities and determination of the MTD. Other endpoints included the rate of objective response (Response Evaluation Criteria In Solid Tumors v.1.1). Results: Twenty-seven patients were enrolled in pacmilimab (mg/kg)+ipilimumab (mg/kg) dose-escalation cohorts: 0.3+3 (n=6); 1+3 (n=3); 3+3 (n=3); 10+3 (n=8); 10+6 (n=6); and 10+10 (n=1). Dose-limiting toxicities occurred in three patients, one at the 0.3+3 dose level (grade 3 dyspnea/pneumonitis) and two at the 10+6 dose level (grade 3 colitis, grade 3 increased aspartate aminotransferase). The MTD and recommended phase 2 dose was pacmilimab 10 mg/kg+ipilimumab 3 mg/kg administered every 3 weeks. Pacmilimab-related grade 3-4 adverse events (AEs) and grade 3-4 immune-related AEs were reported in nine (33%) and six (22%) patients, respectively. Three patients (11%) discontinued treatment because of AEs. The overall response rate was 19% (95% CI 6.3 to 38.1), with one complete (anal squamous cell carcinoma) and four partial responses (cancer of unknown primary, leiomyosarcoma, mesothelioma, testicular cancer). Responses lasted for >12 months in four patients. Conclusions: The MTD and recommended phase 2 dose of pacmilimab (10 mg/kg)+ipilimumab (3 mg/kg) every 3 weeks is active and has a favorable tolerability profile.Citation
Sanborn RE, Hamid O, de Vries EG, Ott PA, Garcia-Corbacho J, Boni V, et al. CX-072 (pacmilimab), a Probody PD-L1 inhibitor, in combination with ipilimumab in patients with advanced solid tumors (PROCLAIM-CX-072): a first-in-human, dose-finding study. J Immunother Cancer. 2021 Jul;9(7):e002446.Journal
Journal for Immunotherapy of CancerDOI
10.1136/jitc-2021-002446PubMed ID
34301808Additional Links
https://dx.doi.org/10.1136/jitc-2021-002446Type
ArticleLanguage
enae974a485f413a2113503eed53cd6c53
10.1136/jitc-2021-002446
Scopus Count
Collections
Related articles
- CX-072 (pacmilimab), a Probody (®) PD-L1 inhibitor, in advanced or recurrent solid tumors (PROCLAIM-CX-072): an open-label dose-finding and first-in-human study.
- Authors: Naing A, Thistlethwaite F, De Vries EGE, Eskens FALM, Uboha N, Ott PA, LoRusso P, Garcia-Corbacho J, Boni V, Bendell J, Autio KA, Randhawa M, Durm G, Gil-Martin M, Stroh M, Hannah AL, Arkenau HT, Spira A
- Issue date: 2021 Jul
- Phase IA/IB study of single-agent tislelizumab, an investigational anti-PD-1 antibody, in solid tumors.
- Authors: Desai J, Deva S, Lee JS, Lin CC, Yen CJ, Chao Y, Keam B, Jameson M, Hou MM, Kang YK, Markman B, Lu CH, Rau KM, Lee KH, Horvath L, Friedlander M, Hill A, Sandhu S, Barlow P, Wu CY, Zhang Y, Liang L, Wu J, Paton V, Millward M
- Issue date: 2020 Jun
- Blocking TIM-3 in Treatment-refractory Advanced Solid Tumors: A Phase Ia/b Study of LY3321367 with or without an Anti-PD-L1 Antibody.
- Authors: Harding JJ, Moreno V, Bang YJ, Hong MH, Patnaik A, Trigo J, Szpurka AM, Yamamoto N, Doi T, Fu S, Calderon B, Velez de Mendizabal N, Calvo E, Yu D, Gandhi L, Liu ZT, Galvao VR, Leow CC, de Miguel MJ
- Issue date: 2021 Apr 15
- Probody Therapeutic Design of (89)Zr-CX-072 Promotes Accumulation in PD-L1-Expressing Tumors Compared to Normal Murine Lymphoid Tissue.
- Authors: Giesen D, Broer LN, Lub-de Hooge MN, Popova I, Howng B, Nguyen M, Vasiljeva O, de Vries EGE, Pool M
- Issue date: 2020 Aug 1
- Combined nivolumab and ipilimumab with or without stereotactic body radiation therapy for advanced Merkel cell carcinoma: a randomised, open label, phase 2 trial.
- Authors: Kim S, Wuthrick E, Blakaj D, Eroglu Z, Verschraegen C, Thapa R, Mills M, Dibs K, Liveringhouse C, Russell J, Caudell JJ, Tarhini A, Markowitz J, Kendra K, Wu R, Chen DT, Berglund A, Michael L, Aoki M, Wang MH, Hamaidi I, Cheng P, de la Iglesia J, Slebos RJ, Chung CH, Knepper TC, Moran-Segura CM, Nguyen JV, Perez BA, Rose T, Harrison L, Messina JL, Sondak VK, Tsai KY, Khushalani NI, Brohl AS
- Issue date: 2022 Sep 24