How was the phase 1/1b expansion cohort designed?
The open-label, multicenter, nonrandomized, first-in-human study evaluated ficerafusp alfa as monotherapy and paired with pembrolizumab in EGFR-driven solid tumors; this analysis reports the HNSCC dose-expansion cohort treated with the combination.1
Eligible patients were 18 years or older with unresectable R/M HNSCC of the oral cavity, oropharynx, hypopharynx, or larynx. That had measurable disease per RECIST 1.1 criteria, an ECOG performance status of 0 or 1, and a tumor PD-L1 CPS of 1 or higher. They were also required to have acceptable hepatic, renal, and hematologic function. Those with prior systemic therapy for R/M disease were excluded; prior platinum, anti-EGFR, or anti–PD-1 treatment for locoregionally advanced disease completed more than 6 months before enrollment was permitted.
Patients received pembrolizumab at 200 mg intravenously on day 1 and ficerafusp alfa at 1500 mg intravenously on days 1, 8, and 15 of 21-day cycles until disease progression, unacceptable toxicity, loss to follow-up, or withdrawal. The primary end point was safety and tolerability; secondary end points included ORR, CBR, DOR, PFS, and OS.
Between February 2022 and April 2023, 42 patients received at least 1 dose (safety set), and 39 were efficacy evaluable. In the HPV-negative cohort (n = 30), the median patient age was 63 years (range, 31-84). More than half of patients were male (63%), and most were White (80%); 63% of patients had an ECOG performance status of 1. Primary disease sites included oral cavity (47%), oropharynx (27%), hypopharynx (13%), and larynx (13%). Half the patients had a CPS of 1 to 19, and the other half had a CPS of 20 or higher.
What were the efficacy outcomes with ficerafusp alfa plus pembrolizumab across HPV subgroups?
Among the 15 HPV-negative responders, 12 (80%) had at least 80% target lesion shrinkage. The probability of maintained response was 65% (95% CI, 40%-90%) at 12 months and 57% (95% CI, 32%-83%) at 18 months.1 The median time to response was 1.4 months (95% CI, 1.4-4.7), and 56% of responses occurred by the first imaging assessment at 6 weeks. Responses were observed across PD-L1 levels: Confirmed ORRs were 54% (95% CI, 25%-81%) in patients with a CPS ranging from 1 to 19 (n = 13) and 53% (95% CI, 25%-81%) in those with a CPS of 20 or higher (n = 15).
In the HPV-positive subgroup (n = 11), the confirmed ORR was 27% (95% CI, 6%-61%), with a CR in 18%; the CBR was 55% (95% CI, 23%-83%). The median PFS was 2.0 months (95% CI, 1.0-10.0), and the median OS was 16.4 months (95% CI, 2.6-25.7).
A subsequent April 2025 assessment showed 24-month OS rates of 46% (95% CI, 23%-65%) in the HPV-negative subgroup and 27% (95% CI, 1.0%-53.6%) in the HPV-positive subgroup. Pharmacodynamic analyses showed complete plasma neutralization of TGF-β1 with minimal effect on TGF-β2, and significant downregulation of intratumoral pSMAD2 after treatment, particularly in HPV-negative tumors.
What was the safety profile of ficerafusp alfa plus pembrolizumab in R/M HNSCC?
Among 42 treated patients, 40 (95%) experienced a treatment-related adverse effect (TRAE). Grade 3 TRAEs occurred in 19 patients (45%), and one patient (2%) had a grade 4 TRAE; no fatal TRAEs were reported.
The most common grade 3 or higher TRAEs were anemia (14%) and acneiform dermatitis (12%), with all other grade 3 or higher TRAEs occurring in 3 or fewer patients. The most frequent any-grade TRAEs were acneiform dermatitis (76%), fatigue (45%), and pruritus (43%).
TRAEs led to ficerafusp alfa discontinuation in 5 patients (12%), with no single TRAE causing discontinuation in more than 1 patient. Investigators reported that infusion-related reactions and mucosal bleeding were generally mild and rarely required dose interruption.
What were the study limitations?
The authors noted limitations, including a single-arm design that precludes isolating the contribution of individual components; limited geographic scope; and the absence of patient-reported outcomes.
“Additionally, information on subsequent treatment after study discontinuation was not collected routinely and could not be analyzed,” the study authors wrote.
What are the next steps for ficerafusp alfa?
A randomized phase 2/3 global trial of first-line ficerafusp alfa plus pembrolizumab vs pembrolizumab monotherapy in PD-L1–positive, HPV-negative R/M HNSCC has been initiated (FORTIFI-HN01; NCT06788990).
References
- Hanna GJ, Zandberg DP, Wong DJ, et al. Ficerafusp alfa (BCA101) with pembrolizumab for recurrent or metastatic head and neck squamous cell carcinoma: two-year results of an expansion cohort of a phase I/Ib trial. J Clin Oncol. Published online May 8, 2026. doi:10.1200/JCO-25-02027
- Harrington KJ, Burtness B, Greil R, et al. Pembrolizumab with or without chemotherapy in recurrent or metastatic head and neck squamous cell carcinoma: updated results of the phase III KEYNOTE-048 study. J Clin Oncol. 2023;41(4):790-802. doi:10.1200/JCO.21.02508
- Burtness B, Harrington KJ, Greil R, et al. Pembrolizumab alone or with chemotherapy versus cetuximab with chemotherapy for recurrent or metastatic squamous cell carcinoma of the head and neck (KEYNOTE-048): a randomised, open-label, phase 3 study. Lancet. 2019;394(10212):1915-1928. doi:10.1016/S0140-6736(19)32591-7
- Black CM, Hanna GJ, Wang L, et al. Real-world treatment patterns and outcomes among individuals receiving first-line pembrolizumab therapy for recurrent/metastatic head and neck squamous cell carcinoma. Front Oncol. 2023;13:1160144. doi:10.3389/fonc.2023.1160144
- Vasiliadou I, Grose D, Wilson C, et al. The use of pembrolizumab monotherapy for the management of head and neck squamous cell carcinoma (HNSCC) in the UK. Int J Cancer. 2024;155(5):883-893. doi:10.1002/ijc.34963