Ramucirumab in combination with pembrolizumab for recurrent or metastatic head and neck squamous cell carcinoma: a single-centre, phase 1/2 trial.

BACKGROUND: VEGF, a key mediator of angiogenesis and resistance to immunotherapy, is overexpressed in head and neck squamous cell carcinoma (HNSCC). We aimed to determine the recommended phase 2 dose of ramucirumab, a selective VEGFR2 inhibitor, given with pembrolizumab and the objective response rate of this combination as first-line treatment for recurrent or metastatic HNSCC. METHODS: In this single-centre, phase 1/2 trial, which was done at Washington University (St Louis, MO, USA), eligible patients were aged 18 years or older with incurable recurrent or metastatic HNSCC and an Eastern Cooperative Oncology Group performance status of 0-2. Patients in phase 2 were required to have had no previous systemic therapy for recurrent or metastatic disease. In a dose de-escalation phase 1 design, patients received ramucirumab (starting dose 10 mg/kg given intravenously) and pembrolizumab (200 mg intravenously) on day 1 of each 21-day cycle. The recommended phase 2 dose of ramucirumab was defined as the highest dose at which one or fewer of three patients had dose-limiting toxicity during cycle one (primary endpoint of phase 1). In a Simon's two-stage phase 2 design, patients received the recommended phase 2 dose of ramucirumab and pembrolizumab. Tumour response (primary endpoint of phase 2) was assessed by Response Evaluation Criteria in Solid Tumours (version 1.1). We hypothesised that there would be an objective response rate of 32% or higher (null ≤13%). Eight or more responses among 33 evaluable patients (those with at least one response assessment) was evidence for activity (80% power; one-sided α=0·05). Analyses were done per protocol. The trial is registered with ClinicalTrials.gov, NCT03650764, and is closed to enrolment. FINDINGS: Between June 18, 2019, and Feb 11, 2021, three patients enrolled and were treated in phase 1 and 37 patients in phase 2. Median age of all patients was 64 years (IQR 59-72). 36 (90%) of 40 patients were men and four (10%) were women, and 36 (90%) patients were White, three (8%) were Black or African American, and one (3%) was Asian. In phase 1, no dose-limiting toxicity event occurred. The recommended phase 2 dose of ramucirumab was 10 mg/kg. Median follow-up for patients on phase 2 was 14·8 months (IQR 4·9-31·0). In phase 2, 18 (55%; 95% CI 38-70) of 33 evaluable patients had an objective response, including confirmed complete response in 11 patients, confirmed partial response in six patients, and unconfirmed partial response in one patient. The most common grade 3 or worse adverse events were dysphagia (14 [38%] of 37 patients), lung infection (11 [30%]), lymphocyte count decrease (ten [27%]), hypophosphataemia (nine [24%]), and hypertension (eight [22%]). No treatment-related deaths were recorded. INTERPRETATION: Ramucirumab and pembrolizumab were safe to administer to patients with recurrent or metastatic HNSCC, and the objective response rate with this combination as first-line treatment for recurrent or metastatic HNSCC was favourable. Further studies of ramucirumab and pembrolizumab in patients with recurrent or metastatic HNSCC are warranted. FUNDING: Lilly and the Joseph Sanchez Foundation.

Trends in ototoxicity monitoring among cisplatin-treated patients with cancer.

PURPOSE: This study aims to characterize patterns in ototoxicity monitoring and identify potential barriers to audiologic follow-up. METHODS: We performed a single-institution retrospective cohort study on adult (≥ 18 years old) cancer patients treated with cisplatin from January 2014 to September 2021. Our primary outcomes were rates of baseline and post-treatment audiograms at the following time points: 3, 6, 12, and greater than 12 months. Time-to-event analyses were performed to describe additional insights to ototoxicity monitoring patterns. RESULTS: Nine hundred fifty-five patients with cancer were included for analysis. The most common primary cancer sites were head and neck (64%), followed by cervical (24%). Three hundred seventy-three patients (39%) underwent baseline audiometric assessment, 38 patients (4%) received audiologic evaluation during chemotherapy, and 346 patients (36%) obtained at least one post-treatment audiogram. Audiologic follow-up was greatest within 3 months of completing chemotherapy (26%), but this tapered dramatically to less than 10% at every other post-treatment time point. Patients with head and neck cancer achieved higher rates of audiologic follow-up at every time point than patients with non-head and neck cancer except for during treatment. CONCLUSIONS: Ototoxicity monitoring is an inconsistent practice, particularly during chemotherapy and for long-term surveillance of hearing loss. Patients with non-head and neck cancer may be at increased risk for loss of audiologic follow-up. IMPLICATIONS FOR CANCER SURVIVORS: Cisplatin ototoxicity is a common occurrence that can be effectively managed with auditory rehabilitation. Therefore, referrals to audiology and counseling on treatment-related ototoxicity are recommended throughout chemotherapy and cancer survivorship.

Targeting Dendritic Cell Dysfunction to Circumvent Anti-PD1 Resistance in Head and Neck Cancer.

PURPOSE: Neoadjuvant anti-PD1 (aPD1) therapies are being explored in surgically resectable head and neck squamous cell carcinoma (HNSCC). Encouraging responses have been observed, but further insights into the mechanisms underlying resistance and approaches to improve responses are needed. EXPERIMENTAL DESIGN: We integrated data from syngeneic mouse oral carcinoma (MOC) models and neoadjuvant pembrolizumab HNSCC patient tumor RNA-sequencing data to explore the mechanism of aPD1 resistance. Tumors and tumor-draining lymph nodes (DLN) from MOC models were analyzed for antigen-specific priming. CCL5 expression was enforced in an aPD1-resistant model. RESULTS: An aPD1-resistant mouse model showed poor priming in the tumor DLN due to type 1 conventional dendritic cell (cDC1) dysfunction, which correlated with exhausted and poorly responsive antigen-specific T cells. Tumor microenvironment analysis also showed decreased cDC1 in aPD1-resistant tumors compared with sensitive tumors. Following neoadjuvant aPD1 therapy, pathologic responses in patients also positively correlated with baseline transcriptomic cDC1 signatures. In an aPD1-resistant model, intratumoral cDC1 vaccine was sufficient to restore aPD1 response by enhancing T-cell infiltration and increasing antigen-specific responses with improved tumor control. Mechanistically, CCL5 expression significantly correlated with neoadjuvant aPD1 response and enforced expression of CCL5 in an aPD1-resistant model, enhanced cDC1 tumor infiltration, restored antigen-specific responses, and recovered sensitivity to aPD1 treatment. CONCLUSIONS: These data highlight the contribution of tumor-infiltrating cDC1 in HNSCC aPD1 response and approaches to enhance cDC1 infiltration and function that may circumvent aPD1 resistance in patients with HNSCC.

Pralsetinib in Patients with Advanced/Metastatic Rearranged During Transfection (RET)-Altered Thyroid Cancer: Updated Efficacy and Safety Data from the ARROW Study.

Background: Rearranged during transfection (RET) alterations are targetable oncogenic drivers in thyroid cancer. Primary data from the open-label, phase 1/2 ARROW study demonstrated clinical activity and manageable safety with pralsetinib, a selective RET inhibitor, in patients with advanced/metastatic RET-altered thyroid cancer. We present an updated analysis with more patients and longer follow-up. Methods: Adult patients with advanced/metastatic RET-mutant medullary thyroid cancer (MTC) or RET fusion-positive thyroid cancer who initiated oral pralsetinib at 400 mg once daily were included. Primary endpoints were overall response rate (ORR) by blinded independent central review (per RECIST v1.1) and safety. Secondary endpoints included duration of response (DoR), progression-free survival (PFS), and overall survival. Responses were assessed in three cohorts of patients with baseline measurable disease: patients with RET-mutant MTC who had received prior cabozantinib and/or vandetanib (C/V), treatment-naïve patients with RET-mutant MTC, and patients with previously treated RET fusion-positive thyroid cancer. Patient-reported outcomes (PROs) were an exploratory endpoint. Results: As of October 18, 2021, the measurable disease population comprised of 61 patients with RET-mutant MTC and prior C/V, 62 treatment-naïve patients with RET-mutant MTC, and 22 patients with RET fusion-positive thyroid cancer who had received prior systemic therapy, including radioactive iodine. The ORR was 55.7% [confidence interval; 95% CI: 42.4-68.5] in patients with RET-mutant MTC and prior C/V, 77.4% [95% CI: 65.0-87.1] in treatment-naïve patients with RET-mutant MTC, and 90.9% [95% CI: 70.8-98.9] in patients with previously treated RET fusion-positive thyroid cancer. Median DoR and median PFS were both 25.8 months in patients with RET-mutant MTC and prior C/V, not reached in treatment-naïve patients with RET-mutant MTC, and 23.6 and 25.4 months, respectively, in patients with previously treated RET fusion-positive thyroid cancer. In the RET-altered thyroid cancer safety population (N = 175), 97.1% of patients reported a treatment-related adverse event (TRAE); these led to discontinuation in 5.7% and dose reduction in 52.6% of patients. There was one death (0.6%) due to a TRAE. PROs improved or remained stable after pralsetinib treatment. Conclusions: In this updated analysis of the ARROW study, pralsetinib continued to show deep and durable clinical activity and a manageable safety profile in patients with advanced/metastatic RET-altered thyroid cancer. Clinical Trial Registration: NCT03037385.

Immune Cell Deconvolution Reveals Possible Association of γδ T Cells with Poor Survival in Head and Neck Squamous Cell Carcinoma.

(1) Background: The role of rare immune cell subtypes in many solid tumors, chief among them head and neck squamous cell carcinoma (HNSCC), has not been well defined. The objective of this study was to assess the association between proportions of common and rare immune cell subtypes and survival outcomes in HNSCC. (2) Methods: In this cohort study, we utilized a deconvolution approach based on the CIBERSORT algorithm and the LM22 signature matrix to infer proportions of immune cell subtypes from 517 patients with untreated HPV-negative HNSCC from The Cancer Genome Atlas. We performed univariate and multivariable survival analysis, integrating immune cell proportions with clinical, pathologic, and genomic data. (3) Results: We reliably deconvolved 22 immune cell subtypes in most patients and found that the most common immune cell types were M0 macrophages, M2 macrophages, and memory resting CD4 T cells. In the multivariable analysis, we identified advanced N stage and the presence of γδ T cells as independently predictive of poorer survival. (4) Conclusions: We uncovered that γδ T cells in the tumor microenvironment were a negative predictor of survival among patients with untreated HNSCC. Our findings underscore the need to better understand the role of γδ T cells in HNSCC, including potential pro-tumorigenic mechanisms, and whether their presence may predict the need for alternative therapy approaches.

Preexisting tumor-resident T cells with cytotoxic potential associate with response to neoadjuvant anti-PD-1 in head and neck cancer.

About 50% of patients with locally advanced head and neck squamous cell carcinoma (HNSCC) experience recurrences after definitive therapy. The presurgical administration of anti-programmed cell death protein 1 (PD-1) immunotherapy results in substantial pathologic tumor responses (pTR) within the tumor microenvironment (TME). However, the mechanisms underlying the dynamics of antitumor T cells upon neoadjuvant PD-1 blockade remain unresolved, and approaches to increase pathologic responses are lacking. In a phase 2 trial (NCT02296684), we observed that 45% of patients treated with two doses of neoadjuvant pembrolizumab experienced marked pTRs (≥50%). Single-cell analysis of 17,158 CD8+ T cells from 14 tumor biopsies, including 6 matched pre-post neoadjuvant treatment, revealed that responding tumors had clonally expanded putative tumor-specific exhausted CD8+ tumor-infiltrating lymphocytes (TILs) with a tissue-resident memory program, characterized by high cytotoxic potential (CTX+) and ZNF683 expression, within the baseline TME. Pathologic responses after 5 weeks of PD-1 blockade were consistent with activation of preexisting CTX+ZNF683+CD8+ TILs, paralleling loss of viable tumor and associated tumor antigens. Response was associated with high numbers of CD103+PD-1+CD8+ T cells infiltrating pretreatment lesions, whereas revival of nonexhausted persisting clones and clonal replacement were modest. By contrast, nonresponder baseline TME exhibited a relative absence of ZNF683+CTX+ TILs and subsequent accumulation of highly exhausted clones. In HNSCC, revival of preexisting ZNF683+CTX+ TILs is a major mechanism of response in the immediate postneoadjuvant setting.

Multidimensional biomarker predicts disease control in response to immunotherapy in recurrent or metastatic head and neck squamous-cell carcinoma.

PURPOSE: Anti-PD-1 therapy provides clinical benefit in 40-50% of patients with relapsed and/or metastatic head and neck squamous cell carcinoma (RM-HNSCC). Selection of anti- PD-1 therapy is typically based on patient PD-L1 immunohistochemistry (IHC) which has low specificity for predicting disease control. Therefore, there is a critical need for a clinical biomarker that will predict clinical benefit to anti-PD-1 treatment with high specificity. METHODS: Clinical treatment and outcomes data for 103 RM-HNSCC patients were paired with RNA-sequencing data from formalin-fixed patient samples. Using logistic regression methods, we developed a novel biomarker classifier based on expression patterns in the tumor immune microenvironment to predict disease control with monotherapy PD-1 inhibitors (pembrolizumab and nivolumab). The performance of the biomarker was internally validated using out-of-bag methods. RESULTS: The biomarker significantly predicted disease control (65% in predicted non-progressors vs. 17% in predicted progressors, p < 0.001) and was significantly correlated with overall survival (OS; p = 0.004). In addition, the biomarker outperformed PD-L1 IHC across numerous metrics including sensitivity (0.79 vs 0.64, respectively; p = 0.005) and specificity (0.70 vs 0.61, respectively; p = 0.009). CONCLUSION: This novel assay uses tumor immune microenvironment expression data to predict disease control and OS with high sensitivity and specificity in patients with RM-HNSCC treated with anti-PD-1 monotherapy.

Memory-like Differentiation, Tumor-Targeting mAbs, and Chimeric Antigen Receptors Enhance Natural Killer Cell Responses to Head and Neck Cancer.

PURPOSE: Head and neck squamous cell carcinoma (HNSCC) is an aggressive tumor with low response rates to frontline PD-1 blockade. Natural killer (NK) cells are a promising cellular therapy for T cell therapy-refractory cancers, but are frequently dysfunctional in patients with HNSCC. Strategies are needed to enhance NK cell responses against HNSCC. We hypothesized that memory-like (ML) NK cell differentiation, tumor targeting with cetuximab, and engineering with an anti-EphA2 (Erythropoietin-producing hepatocellular receptor A2) chimeric antigen receptor (CAR) enhance NK cell responses against HNSCC. EXPERIMENTAL DESIGN: We generated ML NK and conventional (c)NK cells from healthy donors, then evaluated their ability to produce IFNγ, TNF, degranulate, and kill HNSCC cell lines and primary HNSCC cells, alone or in combination with cetuximab, in vitro and in vivo using xenograft models. ML and cNK cells were engineered to express anti-EphA2 CAR-CD8A-41BB-CD3z, and functional responses were assessed in vitro against HNSCC cell lines and primary HNSCC tumor cells. RESULTS: Human ML NK cells displayed enhanced IFNγ and TNF production and both short- and long-term killing of HNSCC cell lines and primary targets, compared with cNK cells. These enhanced responses were further improved by cetuximab. Compared with controls, ML NK cells expressing anti-EphA2 CAR had increased IFNγ and cytotoxicity in response to EphA2+ cell lines and primary HNSCC targets. CONCLUSIONS: These preclinical findings demonstrate that ML differentiation alone or coupled with either cetuximab-directed targeting or EphA2 CAR engineering were effective against HNSCCs and provide the rationale for investigating these combination approaches in early phase clinical trials for patients with HNSCC.

Tipifarnib Potentiates the Antitumor Effects of PI3Kα Inhibition in PIK3CA- and HRAS-Dysregulated HNSCC via Convergent Inhibition of mTOR Activity.

Outcomes for patients with recurrent/metastatic (R/M) head and neck squamous cell carcinoma (HNSCC) are poor, with median overall survival (OS) ranging from 6 to 18 months. For those who progress on standard-of-care (chemo)immunotherapy, treatment options are limited, necessitating the development of rational therapeutic strategies. Toward this end, we targeted the key HNSCC drivers PI3K-mTOR and HRAS via the combination of tipifarnib, a farnesyltransferase (FTase) inhibitor, and alpelisib, a PI3Kα inhibitor, in multiple molecularly defined subsets of HNSCC. Tipifarnib synergized with alpelisib at the level of mTOR in PI3Kα- or HRAS-dependent HNSCCs, leading to marked cytotoxicity in vitro and tumor regression in vivo. On the basis of these findings, the KURRENT-HN trial was launched to evaluate the effectiveness of this combination in PIK3CA-mutant/amplified and/or HRAS-overexpressing R/M HNSCC. Preliminary evidence supports the clinical activity of this molecular biomarker-driven combination therapy. Combined alpelisib and tipifarnib has potential to benefit >45% of patients with R/M HNSCC. By blocking feedback reactivation of mTORC1, tipifarnib may prevent adaptive resistance to additional targeted therapies, enhancing their clinical utility. SIGNIFICANCE: The mechanistically designed, biomarker-matched strategy of combining alpelisib and tipifarnib is efficacious in PIK3CA- and HRAS-dysregulated head and neck squamous carcinoma and could improve outcomes for many patients with recurrent, metastatic disease. See related commentary by Lee et al., p. 3162.

Hearing Outcomes in a Deintensification Trial of Adjuvant Therapy for HPV-Related Oropharyngeal Squamous Cell Carcinoma.

OBJECTIVE: To explore whether deintensification of adjuvant therapy reduces ototoxicity among patients with human papillomavirus (HPV)-related oropharyngeal squamous cell carcinoma (OPSCC). STUDY DESIGN: Retrospective cohort study. SETTING: Single academic center. METHODS: The ototoxicity rate among adult patients with HPV-related OPSCC enrolled in the Minimalist Trial (MINT), a prospective phase 2 trial of surgery followed by risk-adjusted deintensified adjuvant therapy (42 Gy radiation given alone or with a single 100 mg/m2 dose of cisplatin), was compared to that among a historical cohort treated with standard adjuvant therapy (60-66 Gy radiation with up to three 100 mg/m2 doses of cisplatin). Ototoxicity was defined as Common Terminology Criteria for Adverse Events v5.0 ≥ Grade 2. Mixed model analysis was performed to investigate the association between deintensified adjuvant therapy and treatment-related hearing loss. RESULTS: A total of 29 patients (58 ears) were analyzed in the MINT cohort, and 27 patients (54 ears) in the historical cohort. The ototoxicity rate was 5% (n = 3/58 ears) in the MINT cohort and 46% (n = 25/54 ears) in the historical cohort (difference, 41%; 95% confidence interval [CI] = 27%-56%). Patients in the MINT cohort demonstrated a 95% decrease in risk of ototoxicity compared to those in the historical cohort (adjusted odds ratio: 0.05, 95% CI = 0.01-0.31). Differences in estimated marginal mean threshold shifts were statistically and clinically significant at frequencies ≥ 3 kHz. CONCLUSION: The deintensified adjuvant therapy given in MINT led to less ototoxicity than standard adjuvant therapy among patients with HPV-related OPSCC.

Audiologic Follow-up in Patients With Head and Neck Cancer Treated With Cisplatin and Radiation.

OBJECTIVES: Evaluate factors associated with adherence to ototoxicity monitoring among patients with head and neck cancer treated with cisplatin and radiation therapy at a tertiary care center. METHODS: We performed a single-institution retrospective cohort study on adults with head and neck cancer treated with cisplatin and radiation therapy who participated in an ototoxicity monitoring program. The primary outcomes were rates of post-treatment audiograms at the following time points: one, three, six, 12, and greater than 12 months. Multivariable logistic regression was performed to identify risk factors associated with complete loss of follow-up after pre-treatment evaluation. RESULTS: Two hundred ninety-four head and neck cancer patients were analyzed. Overall, 220 (74.8%) patients had at least one post-treatment audiogram; 58 (20.0%) patients had more than one audiogram. The time point with the highest follow-up rate was at 3 months (n = 170, 57.8%); rates at the remaining times ranged from 7.1% to 14.3%. When controlling for covariates, patients without insurance and those with stage IV cancers were associated with complete loss of audiologic follow-up (aOR = 7.18, 95% CI = 2.75-19.90; aOR = 1.96, 95% CI = 1.02-3.77, respectively). Among 156 patients recommended for a hearing aid, only 39 (24.8%) patients received one. CONCLUSIONS: Head and neck cancer patients enrolled in an ototoxicity monitoring program demonstrate moderately high follow-up rates for at least one post-treatment audiogram. However, follow-up tapers dramatically after 6 months, and overall hearing aid utilization is low. Further research is needed to understand barriers to long-term audiologic follow-up and hearing aid utilization to decrease untreated hearing loss in cancer survivorship. LEVEL OF EVIDENCE: Level 3 Laryngoscope, 133:3161-3168, 2023.

Integrated analysis of genomic and transcriptomic data for the discovery of splice-associated variants in cancer.

Somatic mutations within non-coding regions and even exons may have unidentified regulatory consequences that are often overlooked in analysis workflows. Here we present RegTools ( www.regtools.org ), a computationally efficient, free, and open-source software package designed to integrate somatic variants from genomic data with splice junctions from bulk or single cell transcriptomic data to identify variants that may cause aberrant splicing. We apply RegTools to over 9000 tumor samples with both tumor DNA and RNA sequence data. RegTools discovers 235,778 events where a splice-associated variant significantly increases the splicing of a particular junction, across 158,200 unique variants and 131,212 unique junctions. To characterize these somatic variants and their associated splice isoforms, we annotate them with the Variant Effect Predictor, SpliceAI, and Genotype-Tissue Expression junction counts and compare our results to other tools that integrate genomic and transcriptomic data. While many events are corroborated by the aforementioned tools, the flexibility of RegTools also allows us to identify splice-associated variants in known cancer drivers, such as TP53, CDKN2A, and B2M, and other genes.

Risk Factors for Functional Outcomes in Advanced Laryngeal Squamous Cell Carcinoma.

OBJECTIVE: Chemoradiation for patients with laryngeal squamous cell carcinoma (SCC) may achieve organ preservation, but appropriate patient selection remains unknown. This study investigates pre-treatment risk factors associated with functional and survival outcomes after radiation-based therapy in patients with advanced laryngeal SCC. METHODS: A retrospective cohort study was performed on 75 adult patients with stage III or IV laryngeal SCC receiving definitive radiation-based therapy from 1997 to 2016 at a tertiary care center. Tracheostomy and gastrostomy dependence were the primary functional outcomes. Multivariable logistic regressions were performed to evaluate relationships between pre-treatment factors and tracheostomy and gastrostomy dependence. Time-to-event analyses were performed to determine risk factors associated with overall survival. RESULTS: Among 75 patients included in the analysis, 30 (40%) patients were tracheostomy dependent and 31 (41%) were gastrostomy tube dependent. The median length of follow-up was 31 months (range = 1 to 142 months). Pre-treatment tracheostomy was a significant predictor of post-treatment tracheostomy (aOR = 13.9, 95% CI = 3.35 to 57.5) and moderate-severe comorbidity was a significant predictor of post-treatment gastrostomy dependence (aOR = 2.96, 95% CI = 1.04 to 8.43). The five-year overall survival was 51% (95% CI = 38 to 64%). Pre-treatment gastrostomy tube dependence was associated with an increased risk of death (aHR = 2.45, 95% CI = 1.09 to 5.53). CONCLUSIONS: Baseline laryngeal functional status and overall health in advanced laryngeal SCC are associated with poor functional outcomes after radiation-based therapy, highlighting the importance of patient selection when deciding between surgical and non-surgical treatment plans. Laryngoscope, 133:594-600, 2023.

The Potential for Selective Cyclin-Dependent Kinase 4/6 Inhibition in the Therapy for Head and Neck Squamous Cell Carcinoma.

ABSTRACT: Preclinical data support investigation of selective CDK4/6 inhibition as a therapeutic strategy for human papillomavirus (HPV)-unrelated head and neck squamous cell carcinoma (HNSCC). Phase 1 clinical trials established the feasibility of combining palbociclib with cetuximab in patients with recurrent or metastatic HNSCC. Nonrandomized phase II trials showed that palbociclib plus cetuximab resulted in efficacy outcomes better than cetuximab in biomarker-unselected, platinum-resistant or cetuximab-resistant, HPV-unrelated HNSCC. A double-blind, randomized phase II trial (PALATINUS) evaluated the efficacy of palbociclib or placebo and cetuximab in patients with biomarker-unselected, platinum-resistant, cetuximab-naive, HPV-unrelated HNSCC. Palbociclib and cetuximab did not significantly prolong overall survival compared with placebo and cetuximab. However, correlative biomarker analyses identified that trends for better overall survival with palbociclib and cetuximab were observed in certain prespecified subsets; the largest reduction in risk of death with palbociclib versus placebo and cetuximab occurred in the subset with CDKN2A mutations. Several phase II-III trials are underway investigating palbociclib in biomarker-selected patients with HPV-unrelated locally advanced or recurrent or metastatic HNSCC.

Neoadjuvant Immunotherapy Strategies in HPV-Related Head-and-Neck Cancer.

Purpose of review: Herein, we review current evidence and future directions of neoadjuvant immunotherapy in HPV-related head and neck squamous cell carcinoma (HNSCC) by describing published data and ongoing clinical trials. Recent findings: Although HNSCCs have shown response to immune checkpoint inhibitors in recurrent/metastatic disease, a limited number of patients benefit from this treatment. There is an expanding interest in clarifying the clinical benefit of immunotherapy in earlier stage disease setting including at initial presentation. Neoadjuvant immunotherapy for HPV-related HNSCCs represents a rational approach, as these cancers bear strong viral antigens. Summary: The majority of patients with HPV-related HNSCC have good prognosis and treatment de-intensification strategies are under evaluation to decrease toxicity and maintain efficacy. On the other hand, a subset of patients with HPV-related HNSCC have a poorer prognosis and additional treatment options are need to improve outcome. Multiple clinical trials are ongoing to evaluate whether neoadjuvant immunotherapy will achieve these goals.

Phase II Study of Enzalutamide for Patients With Androgen Receptor-Positive Salivary Gland Cancers (Alliance A091404).

PURPOSE: The androgen receptor (AR) is expressed (+) in a subset of salivary gland cancers (SGCs). This phase II trial evaluated the efficacy of the antiandrogen enzalutamide in AR+ SGC. METHODS: Patients with locally advanced/unresectable or metastatic AR+ SGCs were enrolled. Enzalutamide (160 mg) was given orally once daily. The primary end point was the best overall response rate per RECIST v1.1 within eight cycles. Confirmed responses in ≥ 5 of 41 patients would be considered promising. Secondary end points were progression-free survival, overall survival, and safety. RESULTS: Forty-six patients were enrolled; 30 (65.2%) received prior systemic therapy, including 13 (28.3%) with AR-targeted drugs. Of seven (15.2%) partial responses (PRs), only two (4.3%) were confirmed per protocol and counted toward the primary end point. Twenty-four patients (52.2%) had stable disease; 15 (32.6%) had progression of disease as best response. Twenty-six patients (56.5%) experienced tumor regression in target lesions; 18 (39.1%) had partial response/stable disease ≥ 6 months. Tumor regressions were observed in female patients (5 of 6 [83.3%]) and those who received prior AR- (6 of 13 [46.2%]) or human epidermal growth factor receptor 2-targeted therapies (5 of 8 [62.5%]). Three patients remained on treatment at data cutoff (duration, 32.2-49.8 months). The median progression-free survival was 5.6 months (95% CI, 3.7 to 7.5); the median overall survival was 17.0 months (95% CI, 11.8 to 30.0). The most common adverse events were fatigue, hypertension, hot flashes, and weight loss. Total and free testosterone levels increased by a mean of 61.2% and 48.8%, respectively, after enzalutamide. CONCLUSION: Enzalutamide demonstrated limited activity in AR+ SGC, failing to meet protocol-defined success in part because of a lack of response durability. Strategies to enhance the efficacy of antiandrogen therapy are needed.

Clinical trial data of Anti-PD-1/PD-L1 therapy for recurrent or metastatic nasopharyngeal Carcinoma: A review.

IMPORTANCE: Anti-programmed cell death receptor-1 (PD-1) therapy is standard of care for incurable recurrent or metastatic non-nasopharyngeal head and neck cancer. In contrast, there are no regulatory agency-approved anti-PD-1 agents indicated for the treatment of recurrent or metastatic nasopharyngeal carcinomas (RM-NPC) in the Western hemisphere, and no standard treatment option exists beyond first-line chemotherapy for RM-NPC. The pace of development of novel systemic therapy regimens for RM-NPC has been slow compared to many other advanced tumor types, leaving an unmet clinical need for these patients with a poor prognosis. OBSERVATIONS: Recent clinical trials have documented the clinical activity of anti-PD-1 therapy in RM-NPC. In particular, randomized clinical trials in the first-line setting have demonstrated significant improvements in progression-free survival (PFS) with the addition of anti-PD-1 therapy to standard chemotherapy. Whether the observed PFS benefits require combination chemoimmunotherapy or can be achieved with chemotherapy followed by crossover to immunotherapy upon progression remains unknown. Ongoing clinical trials are exploring novel anti-PD-1 therapy-based combinations, which may further solidify a role for these agents in RM-NPC. CONCLUSIONS AND RELEVANCE: Among patients with RM-NPC, anti-PD-1 therapy added to first-line standard-of-care gemcitabine plus cisplatin provides significantly better efficacy outcomes compared to chemotherapy alone, and anti-PD-1 monotherapy appears to have comparable clinical activity and better tolerability than chemotherapy in previously treated disease. Thus, anti-PD-1 therapy is poised to advance standard of care for the treatment of RM-NPC.

First-in-human phase 1/1b study to evaluate sitravatinib in patients with advanced solid tumors.

Sitravatinib (MGCD516), a spectrum-selective receptor tyrosine kinase inhibitor targeting TAM (TYRO3, AXL, MERTK) and split kinase family receptors, has demonstrated preclinical anti-tumor activity and modulation of tumor microenvironment. This first-in-human phase 1/1b study included sitravatinib dose exploration and anti-tumor activity evaluation in selected patients with advanced solid tumors. Primary objectives included assessment of safety, pharmacokinetics and clinical activity of sitravatinib. Secondary objectives included identifying doses for further investigation and exploring molecular markers for patient selection. In phase 1, 32 patients received 10-200 mg, while phase 1b dose expansion comprised 161 patients (150 mg n = 99, 120 mg n = 62). Maximum tolerated dose was determined as 150 mg daily. Dose-limiting toxicity was reported in 4/28 evaluable phase 1 patients (three at 200 mg, one at 80 mg). In phase 1b, 120 mg was defined as the recommended dose due to tolerability. Treatment-related adverse events (TRAEs) were experienced by 174/193 patients (90.2%); grade ≥ 3 TRAEs in 103 patients (53.4%). Most common TRAEs were diarrhea, fatigue, hypertension and nausea; TRAEs led to treatment discontinuation in 26 patients (13.5%) and death in one patient. Sitravatinib was steadily absorbed and declined from plasma with a terminal elimination half-life of 42.1-51.5 h following oral administration. Overall objective response rate was 11.8% in phase 1b, 13.2% in patients with non-small cell lung cancer (NSCLC) and 4.2% in patients with NSCLC with prior checkpoint inhibitor experience. Sitravatinib demonstrated manageable safety and modest clinical activity in solid tumors. NCT02219711 (first posted August 14, 2014).

Phase II Trial of CDX-3379 and Cetuximab in Recurrent/Metastatic, HPV-Negative, Cetuximab-Resistant Head and Neck Cancer.

In phase I development, CDX-3379, an anti-ErbB3 monoclonal antibody, showed promising molecular and antitumor activity in head and neck squamous cell carcinoma (HNSCC), alone or in combination with cetuximab. Preliminary biomarker data raised the hypothesis of enhanced response in tumors harboring FAT1 mutations. This phase II, multicenter trial used a Simon 2-stage design to investigate the efficacy of CDX-3379 and cetuximab in 30 patients with recurrent/metastatic, HPV-negative, cetuximab-resistant HNSCC. The primary endpoint was objective response rate (ORR). Secondary endpoints included ORR in patients with somatic FAT1 mutations, progression-free survival (PFS), overall survival (OS), and safety. Thirty patients were enrolled from March 2018 to September 2020. The ORR in genomically unselected patients was 2/30 (6.7%; 95% confidence interval [CI], 0.8-22.1). Median PFS and OS were 2.2 (95% CI: 1.3-3.6) and 6.6 months (95% CI: 2.7-7.5), respectively. Tissue was available in 27 patients including one of two responders. ORR was 1/10 (complete response; 10%; 95% CI 0.30-44.5) in the FAT1-mutated versus 0/17 (0%; 95% CI: 0-19.5) in the FAT1-wildtype cohorts. Sixteen patients (53%) experienced treatment-related adverse events (AEs) ≥ grade 3. The most common AEs were diarrhea (83%) and acneiform dermatitis (53%). Dose modification was required in 21 patients (70%). The modest ORR coupled with excessive, dose-limiting toxicity of this combination precludes further clinical development. Dual ErbB3-EGFR inhibition remains of scientific interest in HPV-negative HNSCC. Should more tolerable combinations be identified, development in an earlier line of therapy and prospective evaluation of the FAT1 hypothesis warrant consideration.

Integrative genomic analysis reveals low T-cell infiltration as the primary feature of tobacco use in HPV-positive oropharyngeal cancer.

Although tobacco use is an independent adverse prognostic feature in HPV(+) oropharyngeal squamous cell carcinoma (OPSCC), the biologic features associated with tobacco use have not been systematically investigated. We characterized genomic and immunologic features associated with tobacco use through whole exome sequencing, mRNA hybridization, and immunohistochemical staining in 47 HPV(+) OPSCC tumors. Low expression of transcripts in a T cell-inflamed gene expression profile (TGEP) was associated with tobacco use at diagnosis and lower overall and disease-free survival. Tobacco use was associated with an increased proportion of T > C substitutions and a lower proportion of expected mutational signatures, but not with increases in mutational burden or recurrent oncogenic mutations. Our findings suggest that rather than increased mutational burden, tobacco's primary and clinically relevant association in HPV(+) OPSCC is immunosuppression of the tumor immune microenvironment. Quantitative assays of T cell infiltration merit further study as prognostic markers in HPV(+) OPSCC.