Phase 2 study of pembrolizumab in patients with advanced rare cancers

Abstract

Background: Patients with advanced rare cancers have poor prognosis and few treatment options. As immunotherapy is effective across multiple cancer types, we aimed to assess pembrolizumab (programmed cell death 1 (PD-1) inhibitor) in patients with advanced rare cancers.

Methods: In this open-label, phase 2 trial, patients with advanced rare cancers whose tumors had progressed on standard therapies, if available, within the previous 6 months were enrolled in nine tumor-specific cohorts and a 10th cohort for other rare histologies. Pembrolizumab 200 mg was administered intravenously every 21 days. The primary endpoint was non-progression rate (NPR) at 27 weeks; secondary endpoints were safety and tolerability, objective response rate (ORR), and clinical benefit rate (CBR).

Results: A total of 127 patients treated between August 15, 2016 and July 27, 2018 were included in this analysis. At the time of data cut-off, the NPR at 27 weeks was 28% (95% CI, 19% to 37%). A confirmed objective response (OR) was seen in 15 of 110 (14%) evaluable patients (complete response in one and partial response in 14). CBR, defined as the percentage of patients with an OR or stable disease ≥4 months, was 38% (n=42). Treatment was ongoing in 11 of 15 patients with OR at last follow-up. In the cohort with squamous cell carcinoma (SCC) of the skin, the NPR at 27 weeks was 36%, ORR 31%, and CBR 38%. In patients with adrenocortical carcinoma (ACC), NPR at 27 weeks was 31%, ORR 15%, and CBR 54%. In the patients with carcinoma of unknown primary (CUP), NPR at 27 weeks was 33%, ORR 23%, and CBR 54%. In the paraganglioma-pheochromocytoma cohort, NPR at 27 weeks was 43%, ORR 0%, and CBR 75%. Treatment-related adverse events (TRAEs) occurred in 66 of 127 (52%) patients, and 12 (9%) had grade ≥3 TRAEs. The most common TRAEs were fatigue (n=25) and rash (n=17). There were six deaths, all of which were unrelated to the study drug.

Conclusions: The favorable toxicity profile and antitumor activity seen in patients with SCC of skin, ACC, CUP, and paraganglioma-pheochromocytoma supports further evaluation of pembrolizumab in this patient population.

Trial registration number: NCT02721732.

Keywords: oncology; tumours.

Conflict of interest statement

Competing interests: AN reports research support and non-financial support from Merck Sharpe grants from NCI, research support from EMD Serono, MedImmune, Healios Onc. Nutrition, Atterocor, Amplimmune, Armo BioSciences, Karyopharm Therapeutics, Incyte, Novartis, Regeneron, Merck, Bristol Myers Squibb, Pfizer, CytomX Therapeutics, Neon Therapeutics, Calithera BioSciences, TopAlliance BioSciences, Eli Lilly, Kymab, and PsiOxus, non-financial support for travel and accommodation from Armo BioSciences, and has served as an advisory board member for Novartis and CytomX Therapeutics outside the submitted work; FM-B reports grants from Novartis/Aduro, Calithera, Bayer, Jounce, CytoMx, eFFECTOR, PUMA Biotechnology, Curis, Millennium, GlaxoSmithkline, Daiichi Sankyo, Abbvie, Guardant Health, Takeda, and Aileron, personal fees for advisory from Inflection Biosciences, Darwin Health and Spectrum, personal fees for consulting from GRAIL, Clearlight Diagnostics, Dialectica, Samsung Bioepis, Aduro, Xencor, Jackson Laboratory, personal fees from OrigiMed, Kolon Life Science and Parexel International, personal fees for consulting/travel related from Pieris, Sumitomo Dainippon, and OrigMed, personal fees for advisory/travel related from Mersana, grants and personal fees for travel related from Taiho, grants and personal fees for Consulting/travel related from Genentech, Debio, and Pfizer, grants and personal fees for consulting from Zymeworks, grants and personal fees for advisory from Seattle Genetics, grants from AstraZeneca outside the submitted work; JH reports grant from Immune Deficiency Foundation, outside the submitted work; JRA reports personal fees from Novartis, Eli Lilly, Orion Pharmaceuticals, Servier Pharma, Peptomyc, and Merck Sharpe, on the advisory board for Novartis, Eli Lilly, Orion Pharmaceuticals, Servier Pharma, Peptomyc, Merck Sharpe & Dome, Kelun Pharma/Klus Pharma, Pfizer, Roche Pharma, and Elipses Pharma, research funding from Bayer, Novartis, Spectrum Pharmaceuticals, Tocagen, Symphogen, BioAtla, Pfizer, GenMab, CytomX, KELUN-BIOTECH, Takeda-Millenium, GlaxoSmithkline, Ipsen, from null, outside the submitted work. SAP-P reports grants from AbbVie, Inc., Aminex Therapeutics, BioMarin Pharmaceutical, Inc., Boehringer Ingelheim, Bristol Myers Squibb, Cerulean Pharma, Inc., Chugai Pharmaceutical Co., Ltd, Curis, Inc., Five Prime Therapeutics, Flex Bio, Inc., Genmab A/S, GlaxoSmithkline, Helix BioPharma Corp., Incyte Corp., Jacobio Pharmaceuticals Co., Ltd, Medimmune, LLC, Medivation, Inc., Merck Sharpe & Dome Corp., NewLink Genetics Corporation/Blue Link Pharmaceuticals, Novartis Pharmaceuticals, Pieris Pharmaceuticals, Inc., Pfizer, Principia Biopharma, Inc., Puma Biotechnology, Inc., Seattle Genetics, Taiho Oncology, Tesaro, Inc., Transthera Bio, and XuanZhu Biopharma, outside the submitted work; RF reports personal fees for serving on advisory board from Ayala and Regeron-Sanofi, personal fees for consultation from Cellestia, and other from Merck, outside the submitted work; MC reports personal fees for consulting from Pfizer Inc., Genentech, Inc., and Apricity Health LLC, personal fees for serving as scientific/advisory committee member from EMD Serono, Inc., and Genentech, Inc., outside the submitted work; SHS reports personal fees from Angiodynamics, non-financial support from Neuwave Medical, Medtronic, and Merit Medical, outside the submitted work; CT reports salary support from Merck, during the conduct of the study; salary support from Merck, and for contract work to perform correlatives from Armo Bioscience, outside the submitted work; MF reports personal fees and non-financial support for speaking engagements and research funding from Stryker, personal fees for serving on advisory board from Biom’Up, Genetech, and Ipsen, outside the submitted work; VS reports clinical trial research funding from Novartis, Bayer, GlaxoSmithkline, Nanocarrier, Vegenics, Celgene, Northwest Biotherapeutics, Berghealth, Incyte, Fujifilm, Pharmamar, D3, Pfizer, Multivir, Amgen, Abbvie, Alfa-sigma, Agensys, Boston Biomedical, Idera Pharma, Inhibrx, Exelixis, Blueprint medicines, Loxo oncology, Takeda and Roche/ Genentech, National Comprehensive Cancer Network, NCI-CTEP and UT MD Anderson Cancer Center, outside the submitted work; DSH reports research/grant funding from Abbvie, Adaptimmune, Amgen, Astra-Zeneca, BMS, Daiichi-Sankyo, Eisai, Fate Therapeutics, Genmab, Ignyta, Kite, Kyowa, Lilly, Medimmune, Merck, Merrimack, Mirati, MIRNA, Molecular Templates, Mologen, NCI-CTEP, Novartis, Pfizer; personal fees from Axiom, Baxter, GLG, Group H, Guidepoint Global, Jannsen, Medscape, Numab, Trieza Therapeutics; research/grant funding and personal fees from Bayer, Genentech, Infinity, LOXO, Seattle Genetics, Takeda; and other from Molecular Match, OncoResponse, Presagia Inc, during the conduct of the study; SP reports personal fees and other for financial relationship/speakers bureau consultant from Tyme, Inc., and 4-D Pharma, outside the submitted work; TAY reports personal fees and other for research support, consulting, speakers bureau from AstraZeneca and Pfizer, personal fees and other for research support, consulting from Bayer, Seattle Genetics, and Vertex Pharmaceuticals, personal fees and other for research support, speakers bureau from Tesaro, personal fees for consultant, speakers bureau from Merck, research support from Jounce, Eli Lilly and Kyowa, personal fees for consultant services from Aduro, Almac, Atrin, Bristol-Meyers Squibb, Calithera, Clovis, Cybrexa, EMD Serono, Ignyta, Jansen, and Roche, outside the submitted work; AMT reports grants from NIH/NCI, during the conduct of the study; grants from EMD Serono, Boston Biomedical, Inc., Verastem Oncology, Karus Therapeutics, Ltd., Immatics Biotechnologies, CPRIT, Tvardi Therapeutics, OBI Pharma, Parker Institute, Tempus, Foundation Medicine, and Placon Therapeutics, for consulting/advisory role from Genentech, Roche Europe, and Covance, outside the submitted work; FJ reports grants from Novartis, Genentech, BioMed Valley Discoveries, Plexxikon, Piqur, Symphogen, Bayer, and Fujifilm Corporation and Upsher-Smith Laboratories, research funding & SAB from Deciphera, SAB from IFM Therapeutics, Synlogic, Gaurdant Health, services as paid consultant & ownership interests in Trovagene, and paid consultant in Immunomet, outside the submitted work; SF reports clinical trial research support from Polaris Pharmaceuticals, Inc., Takeda., Lilly, Astra Zeneca, Endocyte, Novartis NIH/NCI, Aprea Therapeutics, Aneropharma Science, OncoMed Pharmaceuticals, Huya Bioscience International, Parexel International, LLC, Medivir AB, New Pharma, Inc, BioAtla LLC, MacroGenics, BeiGene, IMV, Inc, and Tolero Pharmaceuticals, outside the submitted work; RMS reports fees for consulting services from Amgen, Bristol-Myers Squibb, Jansen, Abbvie, Pfizer, Innocrin Therapeutics, Tessa Therapeutics during the conduct of the study; MAH reports grants from Exelixis Inc, grants and personal fees from Eisai Inc, and HRA Pharma, outside the submitted work. BS, DDK, RRC, CJ, KPR, S-MT, LW, CB, NT, VR, SK, JMP, AA (Abonofal), JG, AA (Alshawa), LMM, MX, SA, EEID, KRH, and GRV declare no competing interests.

© Author(s) (or their employer(s)) 2020. Re-use permitted under CC BY-NC. No commercial re-use. See rights and permissions. Published by BMJ.

Figures

Figure 1

Radiological response to pembrolizumab treatment. The figure illustrates the best overall response to pembrolizumab treatment using the immune-related Response Evaluation Criteria in Solid Tumors (irRECIST) in four tumor-specific cohorts. The values shown are the maximum percentage change from baseline in the sum of the longest diameters of all target lesions and any new lesions in patients receiving pembrolizumab. Each bar represents a patient. Five of six patients who derived benefit from continuing on the treatment after an initial assessment of PD by RECIST V.1.1 (pseudoprogression) are represented in the figure. The sixth patient who had pseudoprogression was enrolled in 10th cohort (not shown). Patients with clinical progression of disease were arbitrarily assigned 20% increase in tumor burden. The dashed line indicates the 30% reduction in tumor burden that is consistent with an objective response to treatment according to irRECIST. In squamous cell carcinoma of skin cohort, response data is not shown for three of the 19 patients enrolled in this cohort; two patients came off treatment prior to first restaging due to withdrawal of consent and patient choice. The third patient had not reached the 9-week response assessment period. Two patients with 100% reduction in target lesions were considered as irPR as irCR could not be confirmed in one patient at the time of data cut-off and the presence of non-target lesion in the other patient precluded the assignment of irCR. Two patients with unconfirmed irPR were considered as irSD for the analysis as one patient withdrew consent from the study and another patient came off treatment due to toxicity prior to the date of data cut-off. In the adrenocortical cancer cohort, response data is not shown for two of the 15 patients enrolled in this cohort as they came off treatment prior to first restaging due to toxicity and PI choice. In the carcinoma of unknown primary cohort, response data is not shown for nine patients as two patients came off treatment prior to first restaging due to withdrawal of consent and seven patients had not reached the 9-week response assessment period. In the paraganglioma–pheochromocytoma cohort, response data is not shown for one patient who had not reached the 9-week response assessment period. One another patient with 56% decrease in the size of the target lesions was considered to have irPD due to the presence of new non-target lesions in the liver, which was confirmed in the subsequent scan. CR, complete response; ir, immune-related; PD, progressive disease; PR, partial response; RECIST, Response Evaluation Criteria in Solid Tumors; SD, stable disease.

Figure 2

Kinetics of tumor measurement during treatment with pembrolizumab. Percentage changes in tumor measurements from baseline per irRECIST during the course of treatment with pembrolizumab by PD-L1 expression levels are shown for all the patients represented in figure 1. Panel (A) squamous cell carcinoma of the skin. Panel (B) adrenocortical carcinoma. Panel (C) carcinoma of unknown primary and Panel (D) paraganglioma–pheochromocytoma. Of the patients represented in figure 1, five patients are not represented in figure 2. Three patients had clinical progression of disease (squamous cell carcinoma of the skin (n=1) and carcinoma of unknown primary (n=2)) and two patients had no measurable disease (squamous cell carcinoma of the skin (n=1) and carcinoma of unknown primary (n=2)). irRECIST, immune-related Response Evaluation Criteria in Solid Tumors; PD-L1, programmed cell death-ligand 1.