866P - Neoadjuvant and adjuvant AK104 in patients with recurrent, resectable squamous cell carcinoma of the head and neck: A phase II study

Background

For recurrent, resectable head and neck squamous cell carcinoma (HNSCC), the efficacy of salvage surgery remains limited, with a 2-year overall survival (OS) of only 25%. Therefore, there is an urgent need to explore new combination to further improve the survival of this patient subset. Therefore, this study aims to explore the efficacy and safety of AK104 (PD-1/CTLA-4 bispecific antibody) before and after salvage surgery in patients with recurrent, resectable HNSCC.

Methods

This was an open-label, single-institutional phase II clinical trial (ChiCTR2400079741). Patients with recurrent, resectable HNSCC received two circles of AK104 (6mg/kg) 2-4 weeks before surgery, followed by maintenance therapy with AK104 for one year. Primary endpoint was 1-year disease free survival (DFS); secondary endpoints were safety, objective response rate (ORR), pathological response and OS.

Results

As of 7 May 2024, 10 patients were enrolled, including 4 with oral cavity, 3 with oropharynx, and 3 with larynx/hypopharynx. Among them, 8 patients had received surgery, while 2 patients just finished preoperative imaging assessment. The confirmed ORR was 50% (5/10), including 1 case with complete response (CR), 4 with partial response, and 5 patients with stable disease radiologically. Of the 8 patients receiving surgery, 2 (25%) cases had a pathological CR, 2 (25%) had a major pathological response (MPR), and 4 cases had no pathological response. With a median follow-up time of 2.2 months (range: 1.6-5.1 months), DFS and OS were both 100%. Treatment-related adverse events (TRAEs) occurred in 25% (4/10) of the patients. All of them were G1-G2 TRAEs, and there were no G3 and G4 TRAEs. No TRAEs led to treatment discontinuation. Most frequent TRAEs were constipation (20%, N=2), hypothyroidism (10%, N=1), myocarditis (10%, N=1), and rash (10%, N=1).

Conclusions

AK104 demonstrated encouraging anti-tumor activity and favorable safety profile in patients with recurrent, resectable HNSCC. AK104 for the treatment of recurrent, resectable HNSCC should be further evaluated.

Clinical trial identification

Editorial acknowledgement

Funding

Akeso Biopharma.

Disclosure

All authors have declared no conflicts of interest.