Effect of time-of-day nivolumab and stereotactic body radiotherapy in metastatic head and neck squamous cell carcinoma: A secondary analysis of a prospective randomized trial.

BACKGROUND: Prior work documented circadian rhythm impacts on efficacy and toxicity of cancer therapies. METHODS: Secondary analysis of prospective, phase II trial of metastatic HNSCC randomized to nivolumab+/-SBRT. Used cutoffs of 1100 and 1630. Timing classified by first infusion or majority of SBRT (e.g., PM SBRT defined by two or three fractions after 1630). RESULTS: Of 62 patients, there was no significant difference in median PFS between AM nivolumab (n = 7, 175 days), PM nivolumab (n = 21, 58 days), or Mid-Day nivolumab (n = 34, 67 days; p = 0.8). There was no significant difference in median PFS with AM SBRT (n = 4, 78 days), PM SBRT (n = 13, 111 days), or Mid-Day SBRT (n = 15, 63 days; p = 0.8). There was no significant difference in Grade 3-4 toxicity or ORR. Sensitivity analyses with other timepoints were negative. CONCLUSIONS: Further work may elucidate circadian impacts on select patients, tumors, and therapies; however, we found no significant effect in this study.

An Analysis of Positron Emission Tomography Maximum Standard Uptake Value Among Patients With Head and Neck Cancer Receiving Photon and Proton Radiation.

PURPOSE: One main advantage of proton therapy versus photon therapy is its precise radiation delivery to targets without exit dose, resulting in lower dose to surrounding healthy tissues. This is critical, given the proximity of head and neck tumors to normal structures. However, proton planning requires careful consideration of factors, including air-tissue interface, anatomic uncertainties, surgical artifacts, weight fluctuations, rapid tumor response, and daily variations in setup and anatomy, as these heterogeneities can lead to inaccuracies in targeting and creating unwarranted hotspots to a greater extent than photon radiation. In addition, the elevated relative biological effectiveness at the Bragg peak's distal end can also increase hot spots within and outside the target area. METHODS AND MATERIALS: The purpose of this study was to evaluate for a difference in positron emission tomography (PET) standard uptake value (SUV) after definitive treatment, between intensity modulated proton therapy (IMPT) and intensity modulated photon therapy (IMRT). In addition, we compared the biologic dose between PET areas of high and low uptake within the clinical target volume-primary of patients treated with IMPT. This work is assuming that the greater SUV may potentially result in greater toxicities. For the purposes of this short communication, we are strictly focusing on the SUV and do not have correlation with toxicity outcomes. To accomplish this, we compared the 3- and 6-month posttreatment fluorodeoxyglucose PET scans for 100 matched patients with oropharyngeal cancer treated definitively without surgery using either IMPT (n = 50) or IMRT (n = 50). RESULTS: Our study found a significant difference in biologic dose between the high- and low-uptake regions on 3-month posttreatment scans of IMPT. However, this difference did not translate to a significant difference in PET uptake in the clinical target volume-primary at 3 and 6 months' follow-up between patients who received IMPT versus IMRT. CONCLUSIONS: Studies have proposed that proton's greater relative biological effectiveness at the Bragg peak could lead to tissue inflammation. Our study did not corroborate these findings. This study's conclusion underscores the need for further investigations with ultimate correlation with clinical toxicity outcomes.

A phase 1 study of concurrent cabozantinib and cetuximab in recurrent or metastatic head and neck squamous cell cancer.

OBJECTIVES: Epidermal growth factor receptor (EGFR) inhibition with cetuximab is a standard treatment for head and neck squamous cell carcinoma (HNSCC). Activation of the receptor tyrosine kinases AXL, MET and VEGFR can mediate resistance to cetuximab. Cabozantinib, a multikinase inhibitor (MKI) targeting AXL/MET/VEGFR, has demonstrated antitumor activity in preclinical models of HNSCC. This investigator- initiated phase I trial evaluated the safety and efficacy of cetuximab plus cabozantinib in patients with recurrent/metastatic (R/M) HNSCC. MATERIALS AND METHODS: Patients received cetuximab concurrently with cabozantinib daily on a 28-day cycle. Using a 3 + 3 dose-escalation design, the primary endpoint was to determine the maximally tolerated dose (MTD) of cabozantinib. Secondary endpoints included overall response rate (ORR), disease control rate (DCR), progression-free survival (PFS), and overall survival (OS) RESULTS: Among the 20 patients enrolled, most had prior disease progression on immune checkpoint inhibitors (95 %), platinum-based chemotherapy (95 %), and cetuximab (80 %). No dose-limiting toxicities were recorded and the MTD for cabozantinib was established to be 60 mg. Grade ≥ 3 adverse events occurred in 65 % of patients (n = 13). ORR was 20 %, with 4 partial responses (PRs). Two PRs were observed in cetuximab-naïve patients (n = 4), with an ORR of 50 % in this subgroup. In the overall population, DCR was 75 %, median PFS was 3.4 months and median OS was 8.1 months. CONCLUSION: Cetuximab plus cabozantinib demonstrated a manageable toxicity profile and preliminary efficacy in patients with heavily treated R/M HNSCC. The combination of cetuximab with MKIs targeting the AXL/MET/VEGFR axis warrants further investigation, including in cetuximab-naïve patients.

Cabozantinib plus ipilimumab/nivolumab in patients with previously treated advanced differentiated thyroid cancer.

BACKGROUND: This investigator-initiated phase II trial aimed to evaluate the efficacy of cabozantinib in combination with nivolumab and ipilimumab (CaboNivoIpi) in previously treated patients with radioactive iodine (RAI)-refractory differentiated thyroid cancer (DTC) (NCT03914300). METHODS: Eligible patients with RAI-refractory DTC who progressed on 1 prior line of VEGFR-targeted therapy received a 2-week run-in of cabozantinib monotherapy followed by CaboNivoIpi for 4 cycles (cycle length = 6 weeks), followed by cabozantinib plus nivolumab (cycle length = 4 weeks) until disease progression. The primary endpoint was objective response rate (ORR) within the first 6 months of treatment. A Simon optimal 2-stage design allowed for an interim analysis after accrual of 10 evaluable patients. At least 5 responses were needed to proceed to stage 2. RESULTS: Among 11 patients enrolled, the median age was 69 years. Prior VEGFR-targeted therapies included lenvatinib, pazopanib, and sorafenib plus everolimus. Median follow-up was 7.9 months. Among 10 evaluable patients, ORR within the first 6 months of treatment was 10% (1 partial response). Median progression-free survival was 9 months [95% CI: 3.0, not reached] and median overall survival was 19.2 months [(95% CI: 4.6, not reached]. Grade 3/4 treatment-related adverse events (AEs) were noted in 55% (6/11) and grade 5 AEs in 18% (2/11) of patients. The most common treatment-related AE was hypertension. The study did not reach its prespecified efficacy threshold. CONCLUSION: CaboNivoIpi had low ORRs and a high rate of grade ≥3 treatment-related AEs. CLINICAL TRIAL REGISTRATION: NCT03914300.

Combination Targeted Therapy with Lenvatinib and Pembrolizumab in Progressive, Radioiodine-Refractory Differentiated Thyroid Cancers.

PURPOSE: Lenvatinib, a potent multi-kinase inhibitor, improves progression-free survival (PFS) in patients with radioiodine (RAI)-refractory differentiated thyroid cancer (DTC); however, most patients experience disease progression, warranting further therapy. We evaluated the efficacy and safety of combination lenvatinib plus pembrolizumab (LP) in these patients. PATIENTS AND METHODS: We enrolled patients with progressive, RAI-refractory DTC that were either naïve to multi-kinase inhibitors (cohort 1) or who had progressed on lenvatinib (cohort 2). Patients received oral lenvatinib daily (cohort 1, 20 mg; cohort 2, dose at progression ) and intravenous pembrolizumab (200 mg) every 21 days. RESULTS: 30 and 27 patients were enrolled in cohort 1 and 2, respectively. Adverse events were consistent with those observed in other cancers. In cohort 1, the confirmed overall response rate (ORR) was 65.5%. There were no complete responses (CR, primary endpoint). The 12 and 18-month PFS were 72.0% and 58.0%, respectively, and median PFS was 26.8 months. In cohort 2, the confirmed ORR was 16% (primary endpoint), and median PFS was 10.0 months (95% CI; 7.0-17.9 months). Tumor histology, driver mutations, and immune-related biomarkers, including PD-L1 expression, thyroid-specific antibody levels, and CD8+ T cell tumor infiltrate, did not correlate with response to therapy. Increased baseline peripheral blood monocytes and neutrophil to lymphocyte ratio were associated with a worse PFS in cohort 1. CONCLUSIONS: Combination lenvatinib plus pembrolizumab may enhance the durability of lenvatinib monotherapy in lenvatinib-naïve patients. Furthermore, the addition of pembrolizumab may be a viable salvage therapy for patients who have progressed on lenvatinib.

Hypoxia-Directed Treatment of Human Papillomavirus-Related Oropharyngeal Carcinoma.

PURPOSE: Standard curative-intent chemoradiotherapy for human papillomavirus (HPV)-related oropharyngeal carcinoma results in significant toxicity. Since hypoxic tumors are radioresistant, we posited that the aerobic state of a tumor could identify patients eligible for de-escalation of chemoradiotherapy while maintaining treatment efficacy. METHODS: We enrolled patients with HPV-related oropharyngeal carcinoma to receive de-escalated definitive chemoradiotherapy in a phase II study (ClinicalTrials.gov identifier: NCT03323463). Patients first underwent surgical removal of disease at their primary site, but not of gross disease in the neck. A baseline 18F-fluoromisonidazole positron emission tomography scan was used to measure tumor hypoxia and was repeated 1-2 weeks intratreatment. Patients with nonhypoxic tumors received 30 Gy (3 weeks) with chemotherapy, whereas those with hypoxic tumors received standard chemoradiotherapy to 70 Gy (7 weeks). The primary objective was achieving a 2-year locoregional control (LRC) of 95% with a 7% noninferiority margin. RESULTS: One hundred fifty-eight patients with T0-2/N1-N2c were enrolled, of which 152 patients were eligible for analyses. Of these, 128 patients met criteria for 30 Gy and 24 patients received 70 Gy. The 2-year LRC was 94.7% (95% CI, 89.8 to 97.7), meeting our primary objective. With a median follow-up time of 38.3 (range, 22.1-58.4) months, the 2-year progression-free survival (PFS) and overall survival (OS) rates were 94% and 100%, respectively, for the 30-Gy cohort. The 70-Gy cohort had similar 2-year PFS and OS rates at 96% and 96%, respectively. Acute grade 3-4 adverse events were more common in 70 Gy versus 30 Gy (58.3% v 32%; P = .02). Late grade 3-4 adverse events only occurred in the 70-Gy cohort, in which 4.5% complained of late dysphagia. CONCLUSION: Tumor hypoxia is a promising approach to direct dosing of curative-intent chemoradiotherapy for HPV-related carcinomas with preserved efficacy and substantially reduced toxicity that requires further investigation.