NISCAHN: A phase II, multicenter nonrandomized trial aiming at evaluating nivolumab (N) in two cohorts of patients (pts) with recurrent/metastatic (R/M) salivary gland carcinoma of the head and neck (SGCHN), on behalf of the Unicancer Head & Neck Group.

Abstract

6083 Background: SGCHN are rare tumors including adenoid cystic carcinoma (ACC) and non-ACC, with no standard systemic treatment for R/M pts. We evaluated N monotherapy in R/M SGCHN pts. Methods: R/M SGCHN pts (ACC or non-ACC) not eligible to local treatment and with centrally confirmed RECIST 1.1 disease progression over the last 6 months were enrolled and received N 3 mg/kg IV, every 2 weeks for a maximum of 12 months (mo). Possibility was given to re-start N in case of progression during the 2-year follow-up phase. Primary endpoint was 6-mo non-progression Rate (NPR 6m ) as per RECIST 1.1. Secondary endpoints included ORR, PFS, OS, and safety. Considering that N would be uninteresting if NPR 6m ≤ 20% and promising if ≥ 40% and using a Fleming’s single-stage design (α: 5% unilateral, power: 90%), at least 14 successes/42 evaluable pts were required for each cohort to be positive. Results: 46 ACC and 52 Non-ACC pts (median age 61 yrs (range 29-81), 43.9% female, 55.1% PS1 and 2.0% PS2) were enrolled and received at least one dose of N. Median treatment duration was 5.5 mo (ACC) and 3.3 (Non-ACC). Median FU was 10.8 mo (ACC) and 8.3 mo (Non-ACC). 95 patients were evaluable for the primary endpoint. NPR 6m was 15/45 pts (33.3%, 90%CI :21.8;46.6) and 7/50 pts (14.0%, 90%CI:6.8;24.7) for ACC and non-ACC pts respectively. 4 (8.7%) partial responses (PR) and 26 (56.5%) stable diseases (SD) were observed in ACC cohort while 2 (3.8%) PR and 22 (42.3%) SD were observed in non-ACC. Median PFS was 4.9 mo (95%CI = 3.4;5.6) in ACC pts and 1.8 mo (95%CI = 1.7;3.5) in non-ACC pts. The most common related adverse events (AE) ( > 10% by cohort) were asthenia, hyperthyroidism, diarrhea, rash, pruritus and hypothyroidism. 7/98 pts (7.1%) presented at least one related AE Grade 3-4 (mainly hepatic) and 9 pts (9.2%) prematurely discontinued Nivolumab due to toxicity. Conclusions: Limited efficacy was observed with N in R/M SGCHN pts. N in combination might be of interest and deserves exploration in ACC pts. Clinical trial information: NCT03132038.