While immune checkpoint inhibitors (ICIs) have ushered in major changes in standards of care for many solid tumor malignancies, primary and acquired resistance is common. Insufficient antitumor T cells, inadequate function of these cells, and impaired formation of memory T cells all contribute to resistance mechanisms to ICI. Adoptive cellular therapy (ACT) is a form of immunotherapy that is rapidly growing in clinical investigation and has the potential to overcome these limitations by its ability to augment the number, specificity, and reactivity of T cells against tumor tissue. ACT has revolutionized the treatment of hematologic malignancies, though the use of ACT in solid tumor malignancies is still in its early stages. There are currently three major modalities of ACT: tumor-infiltrating lymphocytes (TILs), genetically engineered T-cell receptors (TCRs), and chimeric antigen receptor (CAR) T cells. TIL therapy involves expansion of a heterogeneous population of endogenous T cells found in a harvested tumor, while TCRs and CAR T cells involve expansion of a genetically engineered T-cell directed toward specific antigen targets. In this review, we explore the potential of ACT as a treatment modality against solid tumors, discuss their advantages and limitations against solid tumor malignancies, discuss the promising therapies under active investigation, and examine future directions for this rapidly growing field.

Head and neck squamous cell carcinoma (HNSCC) is the most common cancer arising in the head and neck region. The most common risk factors are smoking, excessive drinking, and human papillomavirus (HPV) infection. While the overall incidence of smoking is decreasing, the incidence of HPV-related HNSCC is increasing in the United States and Western Europe, which led to a shift in understanding of the pathophysiology, treatment, and prognosis of this disease. The outcomes for non-metastatic HNSCC remains very encouraging and continues to improve. Advances in radiation technology and techniques, better organ preserving surgical options, and multidisciplinary treatment modalities have improved cure rates for locally advanced HNSCC patients. The treatment of metastatic disease, however, remains an area of need. The advancement of immune checkpoint inhibitors has provided significantly better outcomes, but only a small proportion of patients obtain benefits. Most recurrent and/or metastatic HNSCC patients continue to have poor survival. This has led to the vigorous investigation of new biomarkers and biomarker-based therapies. Novel therapeutic options including adaptive cellular therapy and therapeutic vaccines are also on the horizon. In this review, we highlight the latest advances in the field of HNSCC and the future direction of research.

MRNA-4157 (V940) is an individualized neoantigen therapy targeting up to 34 patient-specific tumor neoantigens to induce T-cell responses and potentiate antitumor activity. We report mechanistic insights into the immunogenicity of mRNA-4157 via characterization of T-cell responses to neoantigens from the first-in-human, phase 1, KEYNOTE-603 study (NCT03313778) in patients with resected non–small cell lung cancer (Part A: 1-mg mRNA-4157, n = 4) or resected cutaneous melanoma (Part D: 1-mg mRNA-4157 + 200-mg pembrolizumab, n = 12). Safety, tolerability, and immunogenicity were assessed. All patients experienced ≥1 treatment-emergent adverse event; there were no grade 4/5 adverse events or dose-limiting toxicities. mRNA-4157 alone induced consistent de novo and strengthened preexisting T-cell responses to targeted neoantigens. Following combination therapy, sustained mRNA-4157-induced neoantigen-specific T-cell responses and expansion of cytotoxic CD8 and CD4 T cells were observed. These findings show the potential of a novel mRNA individualized neoantigen therapy approach in oncology. Significance: The safety and immunogenicity results from this phase 1 study of mRNA-4157 as adjuvant monotherapy or combination therapy with pembrolizumab show generation of de novo and enhancement of existing neoantigen-specific T-cell responses and provide mechanistic proof of concept to support further development of mRNA-4157 for patients with resected solid tumors. See related commentary by Berraondo et al., p. 2021

PURPOSE: To provide evidence-based recommendations for practicing physicians and other health care providers on immunotherapy and biomarker testing for head and neck cancers. METHODS: ASCO convened an Expert Panel of medical oncology, surgical oncology, radiation oncology, radiology, pathology, and patient advocacy experts to conduct a literature search, including systematic reviews, meta-analyses, randomized controlled trials, and prospective and retrospective comparative observational studies published from 2000 through 2022. Outcomes of interest included survival, overall response, and locoregional control. Expert Panel members used available evidence and informal consensus to develop evidence-based guideline recommendations. RESULTS: The literature search identified 28 relevant studies to inform the evidence base for this guideline. RECOMMENDATIONS: When possible, evidence-based recommendations were developed to address biomarker testing, first-line treatment regimens based on programmed death ligand-1 scores, immunotherapy in platinum-refractory recurrent or metastatic head and neck squamous cell carcinoma, immunotherapy in nasopharyngeal carcinoma, and radiation therapy in combination with immunotherapy for treatment of local recurrence. Additional information is available at www.asco.org/head-neck-cancer-guidelines .

Purpose: A phase II multi-institutional clinical trial was conducted to determine overall survival (OS) in patients with recurrent and/or metastatic (R/M) head and neck squamous cell carcinoma (HNSCC) treated with a combination of cetuximab and nivolumab. Patients and Methods: Patients with R/M HNSCC were treated with cetuximab 500 mg/m2 i.v. on day 14 as a lead-in followed by cetuximab 500 mg/m2 i.v. and nivolumab 240 mg i.v. on day 1 and day 15 of each 28-day cycle. Expression of p16 and programmed cell death-ligand 1 (PD-L1) in archived tumors were determined. Tumor-tissue–modified human papillomavirus (TTMV) DNA was quantified in plasma. Results: Ninety-five patients were enrolled, and 88 patients were evaluable for OS with a median follow-up of 15.9 months. Median OS in the 45 patients who had prior therapy for R/M HNSCC (cohort A) was 11.4 months, with a 1 year OS 50% [90% confidence interval (CI), 0.43–0.57]. Median OS in the 43 patients who had no prior therapy (cohort B) was 20.2 months, with a 1-year OS 66% (90% CI, 0.59–0.71). In the combined cohorts, the p16-negative immunostaining was associated with higher response rate (RR; P = 0.02) but did not impact survival while higher PD-L1 combined positive score was associated with higher RR (P = 0.03) and longer OS (log-rank P = 0.04). In the p16-positive patients, lower median (1,230 copies/mL) TTMV DNA counts were associated with higher RR (P = 0.01) and longer OS compared with higher median (log-rank P = 0.05). Conclusions: The combination of cetuximab and nivolumab is effective in patients with both previously treated and untreated R/M HNSCC and warrants further evaluation.

Chimeric antigen receptor (CAR) T-cell therapy can lead to durable responses in patients with relapsed/refractory hematologic malignancies. Immune effector cell-associated neurotoxicity syndrome (ICANS) and cytokine release syndrome (CRS) are common and may place patients at risk for longer-term cognitive impairment. This study examined changes in cognition in the first year after CD19-directed CAR-T-cell therapy for lymphoma, as well as CAR T-cell therapy-specific risk-factors (e.g., ICANS, CRS) and non-specific risk factors (e.g., baseline quality of life, frailty) for worsening cognition. Patients’ perceived cognition was assessed at baseline and at days 90 and 360. Clinical variables were abstracted from medical records. Piecewise mixed models were used to examine acute change (i.e., within 90 days) and longer-term change (i.e., from 90 days to 360 days) in cognition as well as to explore risk factors for worsening cognition. Among 118 participants (mean age 61, 59% male), mean levels of perceived cognition did not change from baseline to day 90 (p values>0.05) but worsened from day 90 to day 360 in global cognition and in the domains of memory, language, organization, and divided attention (p values<0.05). Although statistically significant, changes were small (d values 0.15-0.28). Greater baseline fatigue, anxiety, and depression were associated with worse global cognition at day 90 (p values<0.01). Patients with more severe ICANS post-CART reported worse global cognition at day 360 (p0.05). Other putative risk factors were not associated with acute or longer-term changes in perceived cognition (p values>0.05). CAR T-cell therapy recipients reported delayed deterioration in several cognitive domains, although changes were small. These findings may be useful when educating future patients on what to expect when receiving CAR T-cell therapy.