Abstract 2186P
Background
Thymic carcinoma (TC) is a rare but highly aggressive cancer, with no standard treatment for patients who progress after platinum-containing chemotherapy.KN046 is a novel bispecific antibody that inhibits both PD-L1/PD1 and CTLA-4/CD80/CD86 pathways. We conducted this phase 2 study aiming to evaluate the efficacy and safety of KN046 in the TC patients who progressed after front-line chemotherapy.
Methods
Patients documented with histologically TC who progressed after platinum-containing chemotherapy were eligible. KN046 was injected intravenously at 5mg/kg Q2W until tumor progression or unacceptable toxicity. The primary endpoint was ORR by IRC, and secondary endpoints were DoR, PFS, OS, and safety. Response was assessed every 8 weeks. PD-L1 expression was measured using 22C3 PharmDx assay.
Results
From Dec 2020 to Dec 2022, 46 patients were enrolled into the study with a median age of 58 (range:38-69) years. There was no difference in gender distribution (male: female=25:21). 22 patients received more than one line of systemic chemotherapy. Most patients (91.3%) had stage IVB disease, ECOG PS was 0 in 10 (21.7%) and 1 in 36 (78.3%) patients, respectively. 17 patients had positve PD-L1, 25 patients had negative PD-L1 and 4 patients were unknown. The median follow-up time was 16.1 months (ranges:11.1-18.6 months). Of 38 evaluable patients, 7 achieved partial response and 17 remained stable disease, while the other 14 experienced progressive disease. The ORR was 16.3% (95%CI: 6.8%, 30.7%), the mDoR was 10.1 months (95%CI: 7.7, NE). The mPFS was 5.6 months (95%CI: 1.9, 12.8). The mOS was immature, the 18-months OS rate was 74.1% (95%CI: 54.29, 86.32). Among the PD-L1-positive patients, the ORR and PFS were numerically higher than that in PD-L1 negative or status unknown, which was 18.8% vs. 14.8% in ORR and 7.6 months vs 5.6 months in PFS. The most common TRAE of any grade include rash (39.1%), ALT increased (32.6%), AST increased (28.3%). 8 patients experienced ≥ grade 3 irAE, 7 (15.2%) patients discontinued study treatment due to TRAE, but there was no death event related with KN046.
Conclusions
KN046 demonstrated promising antitumor activity and acceptable toxicity in thymic carcinoma patients who have received at least one line of chemotherapy.
Clinical trial identification
NCT04469725.
Editorial acknowledgement
Legal entity responsible for the study
Alphamab Oncology.
Funding
Alphamab Oncology.
Disclosure
All authors have declared no conflicts of interest.
Resources from the same session
2172P - Development and evaluation of the usefulness of an immune-related adverse events interview application
Presenter: AKIKO YANO
Session: Poster session 07
2173P - Exploring the complex needs of older patients receiving targeted therapies and immune checkpoint inhibitors for renal and skin cancers at the Royal Marsden Hospital
Presenter: Niamh Cunningham
Session: Poster session 07
2174P - The impact of exposure to antibiotic (ATB) and proton pump inhibitor (PPI) therapy on immune checkpoint inhibitor (ICI) treatment on overall survival (OS): A population-based study
Presenter: Lawson Eng
Session: Poster session 07
2175P - Sex and age-related differences in immunotherapy-induced toxicities
Presenter: Mafalda Teixeira da Costa
Session: Poster session 07
2176P - Rechallenge of immune checkpoint inhibitors after immune-related adverse events: A systematic review
Presenter: Jin Young Kim
Session: Poster session 07
2177P - Immunotherapy adverse events association with inflammation scores: A real-world data analysis from a Portuguese hospital
Presenter: Catarina Fernandes
Session: Poster session 07
2179P - Prospective monitoring of autoimmune events in cancer immunotherapy patients: A report on the first 658 patients in the PRAISE study
Presenter: Eden Sebbag
Session: Poster session 07
2180P - Detrimental effect of an early exposure to antibiotics on the outcomes of immunotherapy in a multi-tumor cohort of patients
Presenter: Víctor Albarrán
Session: Poster session 07
2181P - Effect of different corticosteroid treatment strategies on checkpoint inhibitors pneumonitis outcomes
Presenter: Hui Guo
Session: Poster session 07
2182P - Patient involvement to improve prospective follow-up: Quality of life data after cancer immunotherapy from the PRAISE study
Presenter: Eden Sebbag
Session: Poster session 07