Zinner, Ralph

Importance The incidence of human papillomavirus type 16 (HPV16–positive) recurrent/metastatic (R/M) head and neck squamous cell carcinoma (HNSCC) is rising. Approved therapies offer a durable response to a minority of patients. Objective To determine the efficacy and safety of a therapeutic HPV16-targeted immunotherapy, PDS0101, in combination with pembrolizumab in participants with HPV16-positive R/M HNSCC, with separate evaluation of immune checkpoint inhibitor (ICI)–naive and ICI-resistant cohorts. Design, Setting, and Participants VERSATILE-002 was a phase 2, open-label, multicenter nonrandomized clinical trial conducted at 26 oncology centers from March 29, 2021, to May 15, 2025, across the US, UK, and Ireland using the Simon 2-stage optimal design. Efficacy analyses were performed on modified intent-to-treat (mITT) population; safety analyses included all participants who received 1 or more doses. Eighty-eight participants with histologically confirmed R/M HPV16-positive HNSCC were enrolled, of whom 87 (98.9%) received treatment and composed the safety population. Seventy five (85.2%) were in the mITT population used for efficacy analyses, of whom 53 (70.7%) were ICI-naive with a programmed cell death ligand 1 combined positive score of 1 or greater and 22 (29.3%) were ICI-resistant. Exposures Pembrolizumab (200 mg, intravenously, every 3 weeks for up to 35 cycles) plus subcutaneous PDS0101 (5 scheduled doses per protocol). Main Outcomes and Measures The primary end point was objective response rate (ORR) per the Response Evaluation Criteria in Solid Tumors , version 1.1, by a masked independent central reviewer. Secondary end points included progression-free survival (PFS), median overall survival (mOS), and safety, with exploratory end points of duration of response, disease control rate, and response rates by programmed cell death ligand 1 status. Results Of the 75 patients in the mITT population, the mean (SD) age was 64.0 (8.3) years; 4 individuals (5%) were female and 71 (95%) were male; and 2 individuals (3%) were Asian, 1 (1%) was Black, 5 (7%) were Hispanic, and 71 (95%) were White. Among 53 ICI-naive participants in the mITT cohort, ORR by the central reviewer was 34.0%, median PFS was 5.3 months (95% CI, 2.10-9.00), and mOS was 39.3 months (95% CI, 23.90 to not evaluable). Among 22 ICI-resistant patients in the mITT cohort, no objective responses were observed and the primary end point (ORR by central reviewer) was not met, but mOS was 14.8 months (95% CI, 8.50-26.00). The treatment was well tolerated, with 13.8% experiencing grade 3 or higher treatment-related adverse events. Conclusions and Relevance The results of this nonrandomized clinical trial suggest that PDS0101 plus pembrolizumab showed antitumor activity in ICI-naive HPV16-positive R/M HNSCC, with favorable safety, response rates, and survival outcomes. The findings support further evaluation in a first-line setting. Trial Registration ClinicalTrials.gov Identifier: NCT04260126

6037 Background: The incidence of HPV-associated head and neck squamous cell carcinoma (HNSCC) continues to rise with over 90% of cases being driven by HPV16. Median overall survival (OS) with pembrolizumab in first-line recurrent/metastatic (R/M) HNSCC is 12.3 months in subjects with CPS ≥1, 10.8 months for CPS ≥1-19, and 14.9 months for CPS ≥20. There is an urgent need to improve survival rates in the growing population of HPV16-positive R/M HNSCC. PDS0101 (Versamune HPV) is an investigational T cell stimulating immunotherapy that unleashes a potent, durable attack against HPV16-positive cancers and is being studied in combination with pembrolizumab. Preliminary results were presented at ASCO 2023. (Price KAR, et al. ASCO 2023. Abstract 6012). Methods: VERSATILE-002 is a single-arm phase 2 study evaluating PDS0101 and pembrolizumab for first-line HPV16-positive R/M HNSCC with CPS ≥1. Subjects received pembrolizumab 200 mg IV Q3W with PDS0101 1 mL SC administered concurrently during Cycles 1, 2, 3, 4, and 12 and pembrolizumab alone for all other Cycles up to Cycle 35 (approx. 2 years). The primary study endpoint is confirmed objective response rate (ORR) per RECIST 1.1. Secondary endpoints include progression-free survival (PFS), OS, and safety. Results: The median follow-up is 18.4 months (range 0.2-42.7 months). The efficacy population consists of 53 subjects: 32 (60%) with CPS ≥1-19 and 21 (40%) with CPS ≥20. The median OS for subjects with CPS ≥1 is 30 months (95% CI 23.9, NE). For the CPS ≥1-19 subgroup, the median OS is 29.5 months (95% CI 15.3, NE). For the CPS ≥20 subgroup, the median OS is 39.3 months (95% CI 18.4, NE). Confirmed response rates by investigator assessment are shown in the Table. Twenty-three subjects are still on study: 3 on treatment and 20 in long-term follow-up. No new safety signals have emerged. The most common TRAEs are injection site reactions, fatigue, headache, and pruritus. Only 19% of subjects experienced Grade ≥3 TRAEs. No subject had a Grade 5 TRAE. Conclusions: These data represent one of the most extended follow-up periods to date of subjects receiving an HPV16-targeted therapy for HPV16-positive R/M HNSCC. The PDS0101 and pembrolizumab combination is well tolerated and has demonstrated deep and durable clinical responses. Median OS is promising in light of historic expectations, both overall and relative to PD-L1 subgroup, and remains durable with continued follow up. The results support further evaluation in a randomized phase 3 study with OS as the primary endpoint. Clinical trial information: NCT04260126 . Summary of results. CPS ≥1-19 (N=32) CPS ≥20 (N=21) CPS ≥1 (N=53) ORR, % 28.1 47.6 35.8 DCR, % 75.0 81.0 77.4 Median DOR, months (95 % CI) 21.8 (4.2, NE) NE (5.6, NE) 21.8 (11.5, NE) Median PFS, months (95% CI) 5.1 (2.4, 8.1) 14.1 (2.1, NE) 6.3 (3.5, 9.0) Median OS, months (95% CI) 29.5 (15.3, NE) 39.3 (18.4, NE) 30.0 (23.9, NE)

LBA8003 The full, final text of this abstract will be available at abstract.asco.org at 7:30 AM (EDT) on Monday, June 3, 2013, and in the Annual Meeting Proceedings online supplement to the June 20, 2013, issue of Journal of Clinical Oncology. Onsite at the Meeting, this abstract will be printed in the Monday edition of ASCO Daily News.

LBA8003 Background: PemC and PCB are regimens used for first-line treatment of advanced NS-NSCLC. The primary objective was to compare progression-free survival without Grade 4 toxicity (G4PFS) between two vs three drug regimen arms. Methods: Patients ≥18 years, Stage IV NS NSCLC, AJCC (v7.0), and ECOG PS 0/1 were enrolled. Patients were randomized (1:1); received 4 cycles of induction (PemC: Pem, 500 mg/m2 and C, AUC = 6; PCB: P, 200 mg/m2, C, AUC = 6, and B, 15 mg/kg) followed by Pem (PemC Arm) or B (PCB Arm) maintenance therapy in the absence of progressive disease or discontinuation. Secondary endpoints were PFS, overall survival (OS), overall response rate (ORR), and disease control rate (DCR). The study was powered for G4PFS; assuming hazard ratio (HR) of 0.75; there was 80% power to detect superiority of PemC over PCB with a 2-sided type I error of 0.10. Efficacy data were analyzed by intent-to-treat principle using the log-rank test for time-to-event variables, and an exact test for ORR and DCR. Safety data were evaluated using CTCAE v3 for patients who received ≥1 dose of study treatment. Results: Patients were randomized to PemC (N = 182) or PCB (N = 179). Baseline factors were balanced between arms: median age 66/66 years; % female 42/42; % PS=0, 47/47; % stage IV M1a 29/30; for PemC vs PCB, median G4PFS (months) was 3.91/2.86 (HR = 0.85, 90% CI 0.7, 1.04, p = 0.176); PFS and OS had HR = 1.06 (95% CI 0.84, 1.35), p = 0.610, and HR = 1.07 (95% CI 0.83, 1.36), p = 0.616, respectively. The ORR (%) 23.6/ 27.4 and DCR (%) 59.9/57.0 were for PemC vs PCB, respectively. Significantly more drug-related grade 3/4 anemia (18.7% vs 5.4%), and thrombocytopenia (24.0% vs 9.6%) were seen on PemC; significantly more grade 3/4 neutropenia (48.8% vs 24.6%) and grade 1/2 alopecia (28.3 % vs 8.2%) were seen on PCB. Conclusions: PemC was not superior to PCB in G4PFS; no difference in PFS or OS was observed for the two- vs three-drug regimens. There were no unexpected toxicities; the toxicity profiles demonstrated distinctions by arm, and both regimens demonstrated tolerability. Clinical trial information: NCT00948675.

Purpose To evaluate the efficacy and toxicity of pemetrexed combined with bevacizumab as second-line therapy for patients with advanced non–small-cell lung cancer (NSCLC) and to correlate allelic variants in pemetrexed-metabolizing genes with clinical outcome. Patients and Methods Patients with previously treated NSCLC received pemetrexed (500 mg/m2 intravenous) combined with bevacizumab (15 mg/kg intravenous) every 3 weeks. The primary end point, evaluated using a one-stage Fleming design for detecting a true success rate of at least 70%, was the proportion of patients who were progression free and on treatment at 3 months. Polymorphisms in genes responsible for pemetrexed transport (reduced folate carrier [SLC19A1]) and metabolism (folylpolyglutamate synthase [FPGS] and gamma-glutamyl hydrolase [GGH]) evaluated in germline DNA (blood) were correlated with treatment outcome. Results Forty-eight evaluable patients (14 females and 34 males) received a median of four cycles (range, one to 20 cycles). The most common grade 3 or 4 nonhematologic adverse events (AEs) were fatigue (13%), dyspnea (10%), and thrombosis (10%). Grade 3 or 4 hematologic AEs were neutropenia (19%) and lymphopenia (13%). Twenty-four (57%; 95% CI, 41% to 72%) of the first 42 patients met the success criteria. Median overall survival (OS) and progression-free survival (PFS) times were 8.6 and 4.0 months, respectively. The exon 6 (2522)C→T polymorphism in SLC19A1 correlated with 3-month progression-free status (P = .01) and with PFS (P = .05). The IVS1(1307)C→T polymorphism in GGH correlated with OS (P = .04). Conclusion The study did not meet its primary end point. However, the median PFS time of 4 months is promising. Pharmacogenetic studies in larger cohorts are needed to definitively identify polymorphisms that predict for survival and toxicity of pemetrexed.