Abstract 71P
Background
Stimulator of interferon genes (STING) pathway activation may enhance the innate and adaptive anti-tumor immune response, and complement anti-tumor activity exhibited by PD-1 blockade. ADU-S100 is a synthetic cyclic dinucleotide that broadly activates all human STING isoforms. We report this ongoing phase II study of ADU-S100 plus pembrolizumab in patients (pts) with no prior systemic treatment for recurrent/metastatic head and neck squamous cell carcinoma (HNSCC). Endpoints include safety, preliminary anti-tumor activity, pharmacokinetics (PK) and immunomodulation.
Methods
Pts with PD-L1 CPS score ≥1% were enrolled into this study with a Simon 2-stage design. ADU-S100 was administered by intratumoral injection of 800 mcg per lesion (up to 2 lesions) day (D) 1 and 8 of a 21D cycle. Pembrolizumab (200 mg) was administered by IV infusion on D1 of each 21D cycle. Plasma concentration-time profiles were completed during cycles 1 and 2. Pharmacodynamic (PD) biomarkers were also assessed.
Results
As of 04 September 2020, 11 pts have been enrolled, 6 pts remain on treatment and 5 pts discontinued (3 for disease progression, 1 withdrew consent, and 1 due to second baseline primary malignancy). This interim analysis shows there are no deaths, dose reductions or treatment discontinuations due to Adverse Events (AEs). Treatment-related serious (S)AEs: Grade (Gr) 3 cytokine release syndrome (n=1), Gr 3 localized edema (n=1), Gr 3 hypophysitis (n=1) and Gr 3 laryngeal edema (n=1). The most frequent (≥3 pts) treatment related AEs: fatigue (n=5), localized edema (n=3), pyrexia (n=3), diarrhea (n=3), nausea (n=3), and anemia (n=3). At the time of data cut-off, 8 of the 11 pts were evaluable for response, 1 had not completed first evaluation and 2 pts withdrew before tumor evaluation. Best overall response (by RECISTv1.1): 4 partial response (PR, 3 confirmed), 1 stable disease and 3 disease progression. Duration of disease control: 9 to 38+wks, with patients ongoing.
Conclusions
These results provide early evidence that ADU-S100 plus pembrolizumab is well tolerated, and enrollment into Stage 2 of Simon’s 2-stage design is underway.
Clinical trial identification
NCT03937141.
Legal entity responsible for the study
Aduro Biotech.
Funding
Aduro Biotech.
Disclosure
D.P. Zandberg: Research grant/Funding (institution): Merck; Research grant/Funding (institution): Bristol Myers-Squibb; Research grant/Funding (institution): AstraZeneca; Research grant/Funding (institution): Aduro Biotech; Research grant/Funding (institution): ISA Therapeutics; Research grant/Funding (institution): Astelles; Research grant/Funding (institution): Glaxo Smith-Kline; Research grant/Funding (institution): Regeneron. R. Ferris: Advisory/Consultancy: Aduro Biotech; Advisory/Consultancy, Research grant/Funding (self), Shareholder/Stockholder/Stock options: Novasenta; Advisory/Consultancy, Research grant/Funding (self), Research grant/Funding (institution): Bristol Myers Squibb; Advisory/Consultancy: EMD Serono; Advisory/Consultancy: MacroGenics, Inc.; Advisory/Consultancy, Research grant/Funding (institution): Merck; Advisory/Consultancy: Numab Therapeutics AG; Advisory/Consultancy: Pfizer; Research grant/Funding (self), Research grant/Funding (institution): Astra-Zeneca/MedImmune; Research grant/Funding (self): Tesaro. R. Mehra: Advisory/Consultancy: Rakuten Medical; Advisory/Consultancy: Bayer; Research grant/Funding (institution), research: AstraZeneca; Research grant/Funding (institution), research: Merck; Research grant/Funding (institution), clinical trial: Innate Pharma; Research grant/Funding (institution), clinical trial: Aduro biotech; Research grant/Funding (institution), clinical trial: Seattle Genetics; Research grant/Funding (institution), clinical trial: Kura; Research grant/Funding (institution), clinical trial: Ayala; Leadership role, Member: NCI Head and Neck Recurrent/Metastatic Task Force; Leadership role, Toxicity Monitor: ECOG-ACRIN Head and Neck committee. J. Kaczmar: Advisory/Consultancy, Member of cSCC advisory board: Regeneron. M.K. Gibson: Advisory/Consultancy, Off label speaker: BMS; Advisory/Consultancy, DSMC: Abbvie; Advisory/Consultancy: Daichi; Advisory/Consultancy: Merck. Y.J. Kim: Advisory/Consultancy: Takeda; Advisory/Consultancy: Mersana; Advisory/Consultancy: Dracen; Leadership role, Study Section: NCI. J. Bauman: Advisory/Consultancy: Cue Biopharma; Research grant/Funding (institution): Aveo; Research grant/Funding (institution): BMS; Research grant/Funding (institution): Celldex; Research grant/Funding (institution): Lilly; Research grant/Funding (institution): Moderna; Research grant/Funding (institution): Novartis; Research grant/Funding (institution): Aduro biotech; Research grant/Funding (institution): AstraZeneca; Leadership role, ASCO Measures Steering Committee: ASCO; Leadership role, Steering Committee Co-Chair: NCI Cancer Prevention. D. Adkins: Advisory/Consultancy, Research grant/Funding (institution): Pfizer; Advisory/Consultancy, Research grant/Funding (institution): Celgene/BMS; Advisory/Consultancy, Research grant/Funding (institution): Eli Lilly; Advisory/Consultancy, Research grant/Funding (institution): Merck; Advisory/Consultancy, Research grant/Funding (institution): Cue Biopharma; Advisory/Consultancy, Research grant/Funding (institution): Aduro biotech; Research grant/Funding (institution): Novartis; Research grant/Funding (institution): AstraZeneca; Research grant/Funding (institution): Atara Bio; Research grant/Funding (institution): Blueprint Medicine; Research grant/Funding (institution): Celldex; Research grant/Funding (institution): Kura; Research grant/Funding (institution): Exelixis; Research grant/Funding (institution): Innate; Research grant/Funding (institution): Sensei; Research grant/Funding (institution): Matrix BioMed; Research grant/Funding (institution): Hookipa; Research grant/Funding (institution): CoFactor; Research grant/Funding (institution): MedImmune. E. Cohen: Advisory/Consultancy: ALX Oncology; Advisory/Consultancy: Ascendis; Advisory/Consultancy: Bayer; Advisory/Consultancy: Bioline RX; Advisory/Consultancy: BMS; Advisory/Consultancy: Debio; Advisory/Consultancy: Dynavax; Advisory/Consultancy: MSD; Advisory/Consultancy: Merck; Advisory/Consultancy: Regeneron; Advisory/Consultancy: Sanofi. B. Burtness: Advisory/Consultancy, Research grant/Funding (institution), Steering committee: Aduro Biotech; Advisory/Consultancy, DSMC: Astrazeneca; Advisory/Consultancy: Celgene; Research grant/Funding (institution): BMS; Research grant/Funding (institution): Merck; Advisory/Consultancy: ALX Oncology; Advisory/Consultancy: Nuvelution; Advisory/Consultancy, DSMC: Kura; Advisory/Consultancy, Steering committee: Macrogenics; Advisory/Consultancy: Rakuten; Advisory/Consultancy: Maverick; Research grant/Funding (institution): Formation Biologics; Research grant/Funding (institution): Advaxis; Advisory/Consultancy, Research grant/Funding (institution): Cue BioPharma; Advisory/Consultancy: Debio. C. Bermingham: Shareholder/Stockholder/Stock options, Full/Part-time employment: Aduro Biotech; Shareholder/Stockholder/Stock options: Exelixis; Shareholder/Stockholder/Stock options: Pfizer. A. Dupage: Shareholder/Stockholder/Stock options: CytomX Therapeutics; Full/Part-time employment: Aduro Biotech. A. Desbien: Shareholder/Stockholder/Stock options, Full/Part-time employment: Aduro Biotech. A. Loi: Full/Part-time employment: Aduro Biotech. D.S.A. Nuyten: Leadership role, Shareholder/Stockholder/Stock options, Chief Medical Officer: Aduro Biotech; Shareholder/Stockholder/Stock options: Merck/ MSD; Shareholder/Stockholder/Stock options: Pfizer; Shareholder/Stockholder/Stock options: BMS; Shareholder/Stockholder/Stock options: GSK; Shareholder/Stockholder/Stock options: Kezar; Shareholder/Stockholder/Stock options: Aveo; Shareholder/Stockholder/Stock options: Nektar; Shareholder/Stockholder/Stock options: Sylogic; Shareholder/Stockholder/Stock options: Sangamo; Shareholder/Stockholder/Stock options: Teva; Shareholder/Stockholder/Stock options: Astrazeneca; Shareholder/Stockholder/Stock options, Spouse/Financial dependant: Turningpoint Therapeutics; Shareholder/Stockholder/Stock options: Abbott Laboratories; Shareholder/Stockholder/Stock options: Amgen; Shareholder/Stockholder/Stock options: Allogene; Shareholder/Stockholder/Stock options: Beigene; Shareholder/Stockholder/Stock options: Novo Nordisk; Shareholder/Stockholder/Stock options: Radius Healthcare; Shareholder/Stockholder/Stock options: Seattle Genetics. N.F. Saba: Advisory/Consultancy: Merck; Advisory/Consultancy: Bluprint; Advisory/Consultancy: CUE; Advisory/Consultancy: GSK; Advisory/Consultancy: Pfizer; Advisory/Consultancy: Biontech; Research grant/Funding (institution): BMS; Research grant/Funding (institution): Exilexis. All other authors have declared no conflicts of interest.