Cemiplimab for Kidney Transplant Recipients With Advanced Cutaneous Squamous Cell Carcinoma

PURPOSE

Cemiplimab is approved for treating locally advanced or metastatic cutaneous squamous cell carcinoma (CSCC). Solid organ transplant recipients have been excluded from immunotherapy trials, given concern for allograft rejection despite their increased risk of skin cancers. Chronic immunosuppression is necessary to prevent organ rejection but may attenuate antitumor response with PD-1 inhibitors.

METHODS

We report a phase I study of cemiplimab for kidney transplant recipients (KTRs) with advanced CSCC. After cross-taper to a mammalian target of rapamycin (mTOR) inhibitor and pulsed dose corticosteroids (prednisone 40 mg once daily, the day before and on days 1-3 of each cycle, followed by 20 mg once daily on days 4-6, then 10 mg once daily until the day before each subsequent cycle), patients received cemiplimab 350 mg intravenously once every 3 weeks for up to 2 years and were assessed for response every 8 weeks. The primary end point was the rate of kidney rejection, with key secondary end points including rate and duration of response, and survival.

RESULTS

Twelve patients were treated. No kidney rejection or loss was observed. A response to cemiplimab was observed in five of 11 evaluable patients (46%; 90% CI, 22 to 73), including two with durable responses beyond a year. Median follow-up was 6.8 months (range, 0.7-29.8). Treatment-related grade 3 or greater adverse events occurred in five patients (42%), including diarrhea, infection, and metabolic disturbances. One patient died of angioedema and anaphylaxis attributed to mTOR inhibitor cross-taper.

CONCLUSION

mTOR inhibitor and corticosteroids represent a favorable immunosuppressive regimen for KTRs with advanced CSCC receiving immunotherapy. This combination resulted in durable antitumor responses with no kidney rejection events (funded by Regeneron Pharmaceuticals [ClinicalTrials.gov identifier: NCT04339062]).

Nivolumab plus ipilimumab in advanced salivary gland cancer: a phase 2 trial

Salivary gland cancers (SGCs) are rare, aggressive cancers without effective treatments when metastasized. We conducted a phase 2 trial evaluating nivolumab (nivo, anti-PD-1) and ipilimumab (ipi, anti-CTLA-4) in 64 patients with metastatic SGC enrolled in two histology-based cohorts (32 patients each): adenoid cystic carcinoma (ACC; cohort 1) and other SGCs (cohort 2). The primary efficacy endpoint (≥4 objective responses) was met in cohort 2 (5/32, 16%) but not in cohort 1 (2/32, 6%). Treatment safety/tolerability and progression-free survival (PFS) were secondary endpoints. Treatment-related adverse events grade ≥3 occurred in 24 of 64 (38%) patients across both cohorts, and median PFS was 4.4 months (95% confidence interval (CI): 2.4, 8.3) and 2.2 months (95% CI: 1.8, 5.3) for cohorts 1 and 2, respectively. We present whole-exome, RNA and T cell receptor (TCR) sequencing data from pre-treatment and on-treatment tumors and immune cell flow cytometry and TCR sequencing from peripheral blood at serial timepoints. Responding tumors universally demonstrated clonal expansion of pre-existing T cells and mutational contraction. Responding ACCs harbored neoantigens, including fusion-derived neoepitopes, that induced T cell responses ex vivo. This study shows that nivo+ipi has limited efficacy in ACC, albeit with infrequent, exceptional responses, and that it could be promising for non-ACC SGCs, particularly salivary duct carcinomas. ClinicalTrials.gov identifier: NCT03172624 .

Enhancing Radioiodine Incorporation in BRAF-Mutant, Radioiodine-Refractory Thyroid Cancers with Vemurafenib and the Anti-ErbB3 Monoclonal Antibody CDX-3379: Results of a Pilot Clinical Trial

Background: Oncogenic activation of mitogen-activated protein kinase (MAPK) signaling is associated with radioiodine refractory (RAIR) thyroid cancer. Preclinical models suggest that activation of the receptor tyrosine kinase erbB-3 (HER3) mitigates the MAPK pathway inhibition achieved by BRAF inhibitors in BRAF^V600E mutant thyroid cancers. We hypothesized that combined inhibition of BRAF and HER3 using vemurafenib and the human monoclonal antibody CDX-3379, respectively, would potently inhibit MAPK activation and restore radioactive iodine (RAI) avidity in patients with BRAF-mutant RAIR thyroid cancer. Methods: Patients with BRAF^V600E RAIR thyroid cancer were evaluated by thyrogen-stimulated iodine-124 (¹²⁴I) positron emission tomography-computed tomography (PET/CT) at baseline and after 5 weeks of treatment with oral vemurafenib 960 mg twice daily alone for 1 week, followed by vemurafenib in combination with 1000 mg of intravenous CDX-3379 every 2 weeks. Patients with adequate ¹²⁴I uptake on the second PET/CT then received therapeutic radioactive iodine (¹³¹I) with vemurafenb+CDX-3379. All therapy was discontinued two days later. Treatment response was monitored by serum thyroglobulin measurements and imaging. The primary endpoints were safety and tolerability of vemurafenib+CDX-3379, as well as the proportion of patients after vemurafenb+CDX-3379 therapy with enhanced RAI incorporation warranting therapeutic ¹³¹I. Results: Seven patients were enrolled; six were evaluable for the primary endpoints. No grade 3 or 4 toxicities related to CDX-3379 were observed. Five patients had increased RAI uptake after treatment; in 4 patients this increased uptake warranted therapeutic ¹³¹I. At 6 months, 2 patients achieved partial response after ¹³¹I and 2 progression of disease. Next-generation sequencing of 5 patients showed that all had co-occurring telomerase reverse transcriptase promoter alterations. A deleterious mutation in the SWItch/Sucrose Non-Fermentable (SWI/SNF) gene ARID2 was discovered in the patient without enhanced RAI avidity after therapy and an RAI-resistant tumor from another patient that was sampled off-study. Conclusions: The endpoints for success were met, providing preliminary evidence of vemurafenib+CDX-3379 safety and efficacy for enhancing RAI uptake. Preclinical data and genomic profiling in this small cohort suggest SWI/SNF gene mutations should be investigated as potential markers of resistance to redifferentiation strategies. Further evaluation of vemurafenib+CDX-3379 as a redifferentiation therapy in a larger trial is warranted (ClinicalTrials.gov: NCT02456701).

A Case of Cefepime-Induced Immune Thrombocytopenia

WHAT IS KNOWN AND OBJECTIVE

Drug-induced immune thrombocytopenia (DITP) is a rare adverse event. It is often diagnosed using clinical risk criteria, but this can create diagnostic uncertainty.

CASE DESCRIPTION

A 35-year-old man with disseminated Serratia marcescens infection developed severe thrombocytopenia. A drug-dependent platelet-reactive antibody test demonstrated cefepime-dependent platelet-reactive antibodies which confirmed the diagnosis of DITP.

WHAT IS NEW AND CONCLUSION

We describe the first case of cefepime-induced DITP confirmed by a drug-dependent platelet-reactive antibody test. To our knowledge, this is the first proven example of DITP in a fourth-generation cephalosporin.

Salivary Gland Cancers

Salivary gland carcinomas are a rare and heterogenous group of cancers with varying underlying biology and clinical behavior. A quickly evolving body of data has advanced the understanding of these tumors, leading to effective therapeutics for several histologic subtypes. Biologically rational clinical trials have developed from an understanding of MYB and NOTCH signaling in adenoid cystic carcinoma. The recognition of androgen receptor signaling and HER2-targeted therapy has offered therapeutic options in non-ACC salivary cancers. The use of TRK inhibitors in salivary secretory carcinoma has led to exceptional responses. Immunotherapy is an exciting new therapeutic avenue that requires further exploration.

Any day, split halfway: Flexibility in scheduling high-dose cisplatin-A large retrospective review from a high-volume cancer center

High-dose (HD) cisplatin remains the standard of care with chemoradiation for locally advanced oropharyngeal cancer (OPC). Cooperative group trials mandate bolus-HD (100 mg/m²  × 1 day, every 3 weeks) cisplatin administration at the beginning of the week to optimize radiosensitization-a requirement which may be unnecessary. This analysis evaluates the impact of chemotherapy administration day of week (DOW) on outcomes. We also report our institutional experience with an alternate dosing schedule, split-HD (50 mg/m²  × 2 days, every 3 weeks). We retrospectively reviewed 435 definitive chemoradiation OPC patients from 10 December 2001 to 23 December 2014. Those receiving non-HD cisplatin regimens or induction chemotherapy were excluded. Data collected included DOW, dosing schedule (bolus-HD vs split-HD), smoking, total cumulative dose (TCD), stage, Karnofsky Performance Status, human papillomavirus status and creatinine (baseline, peak and posttreatment baseline). Local failure (LF), regional failure (RF), locoregional failure (LRF), distant metastasis (DM), any failure (AF, either LRF or DM) and overall survival (OS) were calculated from radiation therapy start. Median follow-up was 8.0 years (1.8 months-17.0 years). DOW, dosing schedule and TCD were not associated with any outcomes in univariable or multivariable regression models. There was no statistically significant difference in creatinine or association with TCD in split-HD vs bolus-HD. There was no statistically significant association between DOW and outcomes, suggesting that cisplatin could be administered any day. Split-HD had no observed differences in outcomes, renal toxicity or TCD compared to bolus-HD cisplatin. Our data suggest that there is some flexibility of when and how to give HD cisplatin compared to clinical trial mandates.

SWI/SNF Complex Mutations Promote Thyroid Tumor Progression and Insensitivity to Redifferentiation Therapies

Mutations of subunits of the SWI/SNF chromatin remodeling complexes occur commonly in cancers of different lineages, including advanced thyroid cancers. Here we show that thyroid-specific loss of Arid1a, Arid2, or Smarcb1 in mouse BRAF^V600E-mutant tumors promotes disease progression and decreased survival, associated with lesion-specific effects on chromatin accessibility and differentiation. As compared with normal thyrocytes, BRAF^V600E-mutant mouse papillary thyroid cancers have decreased lineage transcription factor expression and accessibility to their target DNA binding sites, leading to impairment of thyroid-differentiated gene expression and radioiodine incorporation, which is rescued by MAPK inhibition. Loss of individual SWI/SNF subunits in BRAF tumors leads to a repressive chromatin state that cannot be reversed by MAPK pathway blockade, rendering them insensitive to its redifferentiation effects. Our results show that SWI/SNF complexes are central to the maintenance of differentiated function in thyroid cancers, and their loss confers radioiodine refractoriness and resistance to MAPK inhibitor-based redifferentiation therapies. SIGNIFICANCE: Reprogramming cancer differentiation confers therapeutic benefit in various disease contexts. Oncogenic BRAF silences genes required for radioiodine responsiveness in thyroid cancer. Mutations in SWI/SNF genes result in loss of chromatin accessibility at thyroid lineage specification genes in BRAF-mutant thyroid tumors, rendering them insensitive to the redifferentiation effects of MAPK blockade.This article is highlighted in the In This Issue feature, p. 995.

A phase II trial cohort of nivolumab plus ipilimumab in patients (Pts) with recurrent/metastatic adenoid cystic carcinoma (R/M ACC)

6084

Background: R/M ACC is a malignant neoplasm most commonly of salivary gland origin with no standard treatment. The impact of combined PD-1/CTLA-4 checkpoint blockade in R/M ACC is unknown. Methods: In a two-stage minimax phase II trial, pts with progressive R/M ACC (non-salivary primaries allowed) were enrolled and treated with nivolumab 3 mg/kg every 2 weeks plus ipilimumab 1 mg/kg every 6 weeks (1 cycle = 6 weeks). Imaging, using RECIST v1.1 response assessment, was scheduled to be performed approximately every 12 weeks. The primary endpoint was overall response rate (ORR = complete response [CR]+partial response [PR]) per RECIST v1.1. To detect a difference between an unacceptable ORR of 5% and a desirable ORR of 20% (one-sided type I error of 10%, power of 90%), at least 1 in the first 18 pts required an observed response. At least 4 responses of 32 total pts were needed to meet the primary endpoint. Treatment beyond progression of disease (PD) was allowed at the discretion of the investigator. A second cohort of pts with non-ACC salivary cancer is still accruing for separate analysis. Results: From 6/12/2017-6/20/2018, 32 pts were enrolled and evaluable for the primary endpoint. There was 1 confirmed PR in the first 18 pts, therefore enrollment of the second stage continued. ORR was 6% (2/32). One additional pt had an unconfirmed PR (-31% regression before CNS PD). For best overall response, there were 2 PRs, 15 SD, and 11 PD. Four pts never reached a first disease assessment: 3 due to death from clinical PD and 1 was removed for toxicity. Six pts discontinued the trial for toxicities (Grade 4 (G4) neutropenia/sepsis and G3 adrenal insufficiency (1), G2 hypophysitis (2), G3 arthritis > 7 days (1), G3 colitis (1), and G3 hepatitis/G4 creatinine kinase (CK) elevation (1)). The 2 confirmed PRs consisted of -73.1% and -58.4% regressions, with a duration of therapy of 18.4 and 7.8 months, respectively (treatment ongoing for both). Conclusions: The study did not meet its primary endpoint, though the responses observed were dramatic. Paired biopsy and peripheral blood samples will be analyzed to elucidate insights into mechanisms of response and resistance to dual checkpoint blockade. Clinical trial information: NCT03172624.

A retrospective analysis of cisplatin dosing strategies when used with radiation on outcomes in head and neck squamous cell carcinoma of the oropharynx

6079

Background: Cis is the gold standard radiosensitizer for CRT to treat head and neck cancer. Prospective trials have required that cis be administered early in the week (Mon/Tues) to optimize radiosensitization without evidence to support this practice. This retrospective analysis considers the impact of cis day of week (DOW) administration and other variables on OPSCC pt outcomes. Methods: We reviewed OPSCC cases treated with primary CRT at our center. Pts treated with non-cis or induction chemotherapy were excluded. Data collected includes age, DOW (Mon/Tues vs Wed/Thurs/Fri), smoking status, total dose (TD) of cis (≤200mg/m2 vs > 200mg/m2), single dose (SiD) [100mg/m2 x1 day] vs split dose (SpD) [50mg/m2 x2 days] administration, T stage (0-2b vs 2c-3), N stage (0-2b vs 2c-3), overall survival (OS) (from start of RT), local/regional/distant failure, KPS and HPV/p16 status. Univariate Cox proportional hazards regression was used to analyze OS and multivariate Cox proportional hazard model investigated the relationships between OS and cis dosing variables while controlling for other factors. Results: 745 pts with OPSCC were treated with CRT from 7/31/2001-2/7/2014. 459 used cis based regimens and were included. Median age at start of RT was 55. 311 pts (67.8%) received SpD, 124 (27%) received SiD, 8 (1.7%) received weekly cis and 16 (3.5) received mixed cycles. 269 (58.6%) received ≤200mg/m2. 232 (50.5%) were HPV/p16 positive, 40 (8.7%) were negative and 187 (40.7%) were unknown. Median f/u was 7.9yrs (1.8m -18.9yrs). There were 92 (20%) deaths, and 75 (16.4%) recurrences (local/regional and distant) with 44 (9.6%) competing events. In univariate analysis, age, N stage, T stage, KPS and HPV/p16 status were significantly associated with OS, while DOW, TD, and SiD/SpD were not. In multivariate analysis (MVA), none of the associations between cis dosing and OS were significant (although MVA was limited by low number of events and total variables included). Conclusions: This retrospective analysis suggests that the DOW cis is given has no impact upon CRT outcomes for OPSCC pts. SpD cis represents an alternative administration approach.

Vemurafenib Redifferentiation of BRAF Mutant, RAI-Refractory Thyroid Cancers

CONTEXT

BRAFV600E mutant thyroid cancers are often refractory to radioiodine (RAI).

OBJECTIVES

To investigate the utility and molecular underpinnings of enhancing lesional iodide uptake with the BRAF inhibitor vemurafenib in patients with RAI-refractory (RAIR).

DESIGN

This was a pilot trial that enrolled from June 2014 to January 2016.

SETTING

Academic cancer center.

PATIENTS

Patients with RAIR, BRAF mutant thyroid cancer.

INTERVENTION

Patients underwent thyrotropin-stimulated iodine-124 (124I) positron emission tomography scans before and after ~4 weeks of vemurafenib. Those with increased RAI concentration exceeding a predefined lesional dosimetry threshold (124I responders) were treated with iodine-131 (131I). Response was evaluated with imaging and serum thyroglobulin. Three patients underwent research biopsies to evaluate the impact of vemurafenib on mitogen-activated protein kinase (MAPK) signaling and thyroid differentiation.

MAIN OUTCOME MEASURE

The proportion of patients in whom vemurafenib increased RAI incorporation to warrant 131I.

RESULTS

Twelve BRAF mutant patients were enrolled; 10 were evaluable. Four patients were 124I responders on vemurafenib and treated with 131I, resulting in tumor regressions at 6 months. Analysis of research tumor biopsies demonstrated that vemurafenib inhibition of the MAPK pathway was associated with increased thyroid gene expression and RAI uptake. The mean pretreatment serum thyroglobulin value was higher among 124I responders than among nonresponders (30.6 vs 1.0 ng/mL; P = 0.0048).

CONCLUSIONS

Vemurafenib restores RAI uptake and efficacy in a subset of BRAF mutant RAIR patients, probably by upregulating thyroid-specific gene expression via MAPK pathway inhibition. Higher baseline thyroglobulin values among responders suggest that tumor differentiation status may be a predictor of vemurafenib benefit.

Phase II Study of Lenvatinib in Patients With Progressive, Recurrent or Metastatic Adenoid Cystic Carcinoma

PURPOSE

Recurrent or metastatic adenoid cystic carcinoma (R/M ACC) is a malignant neoplasm of predominantly salivary gland origin for which effective therapies are lacking. We conducted a phase II trial evaluating the multitargeted tyrosine kinase inhibitor lenvatinib in patients with R/M ACC.

PATIENTS AND METHODS

This study was conducted with a two-stage minimax design. Patients with histologically confirmed R/M ACC of any primary site with radiographic and/or symptomatic progression were eligible. Any prior therapy was allowed except previous lenvatinib. Patients received lenvatinib 24 mg orally per day. The primary end point was overall response rate. Secondary end points were progression-free survival and safety. An exploratory analysis of how MYB expression and genomic alterations relate to outcomes was conducted.

RESULTS

Thirty-three patients were enrolled; 32 were evaluable for the primary end point. Five patients (15.6%) had a confirmed partial response, 24 patients (75%) had stable disease, two patients (6.3%) discontinued treatment as a result of toxicity before the first scan, and one patient (3.1%) had progression of disease as best response. Median progression-free survival time was 17.5 months (95% CI, 7.2 months to not reached), although only eight progression events were observed. Patients otherwise were removed for toxicity (n = 5), as a result of withdrawal of consent (n = 9), or at the treating physician's discretion (n = 6). Twenty-three patients required at least one dose modification, and 18 of 32 patients discontinued lenvatinib for drug-related issues. The most common grade 3 or 4 adverse events were hypertension (n = 9; 28.1%) and oral pain (n = 3; 9.4%). Three grade 4 adverse events were observed (myocardial infarction, n = 1; posterior reversible encephalopathy syndrome, n = 1; and intracranial hemorrhage, n = 1).

CONCLUSION

This trial met the prespecified overall response rate primary end point, demonstrating antitumor activity with lenvatinib in R/M ACC patients. Toxicity was comparable to previous studies, requiring monitoring and management.

The Effect of Rubric-Guided, Focused, Personalized Coaching Sessions and Video-Recorded Presentations on Teaching Skills Among Fourth-Year Medical Students: A Pilot Study

PROBLEM

As medical students become residents, teaching becomes an expected and integral responsibility. Yet, training-for-teaching opportunities are lacking. In 2014, the authors designed a pilot study using rubric-guided, focused, personalized coaching sessions and video-recorded presentations to improve student teaching skills among fourth-year students at Harvard Medical School.

APPROACH

In 2014-2015, the authors recruited students from an elective on how to tutor preclinical students for the pilot, which consisted of four phases: a precoaching teaching presentation, a 30- to 45-minute coaching session, a postcoaching teaching presentation, and blinded reviewer ratings. Students' pre- and postcoaching presentations were video recorded. Using a scoring rubric for 15 teaching skills, students rated their pre- and postcoaching videos. Blinded reviewers also rated the pre- and postcoaching presentations using the same rubric with an additional category to gauge their overall impression.

OUTCOMES

Fourteen students completed all four phases of the pilot. Students' ratings demonstrated statistically significant improvement in several teaching skills, including presentation content (P < .001), rate of speech (P = .001), and opening statement and learning objectives (P = .004). Blinded reviewers' ratings demonstrated statistically significant improvements in several teaching skills, including opening statement and learning objectives (P < .001), overall impression (P = .001), and conclusion and summary of learning objectives (P = .004). Students provided largely positive comments on the interventions.

NEXT STEPS

The authors will work toward addressing limitations in the rubric, using coaching in different teaching settings, addressing the interventions' generalizability, training coaches, and performing additional evaluations.

Brain MRS glutamine as a biomarker to guide therapy of hyperammonemic coma

Acute idiopathic hyperammonemia in an adult patient is a life-threatening condition often resulting in a rapid progression to irreversible cerebral edema and death. While ammonia-scavenging therapies lower blood ammonia levels, in comparison, clearance of waste nitrogen from the brain may be delayed. Therefore, we used magnetic resonance spectroscopy (MRS) to monitor cerebral glutamine levels, the major reservoir of ammonia, in a gastric bypass patient with hyperammonemic coma undergoing therapy with N-carbamoyl glutamate and the ammonia-scavenging agents, sodium phenylacetate and sodium benzoate. Improvement in mental status mirrored brain glutamine levels, as coma persisted for 48h after plasma ammonia normalized. We hypothesize that the slower clearance for brain glutamine levels accounts for the delay in improvement following initiation of treatment in cases of chronic hyperammonemia. We propose MRS to monitor brain glutamine as a noninvasive approach to be utilized for diagnostic and therapeutic monitoring purposes in adult patients presenting with idiopathic hyperammonemia.

Clonal Hematopoiesis Associated With Adverse Outcomes After Autologous Stem-Cell Transplantation for Lymphoma

Purpose Clonal hematopoiesis of indeterminate potential (CHIP) is an age-related condition characterized by somatic mutations in the blood of otherwise healthy adults. We hypothesized that in patients undergoing autologous stem-cell transplantation (ASCT) for lymphoma, CHIP at the time of ASCT would be associated with an increased risk of myelodysplastic syndrome and acute myeloid leukemia, collectively termed therapy-related myeloid neoplasm (TMN), and other adverse outcomes. Methods We performed whole-exome sequencing on pre- and post-ASCT samples from 12 patients who developed TMN after autologous transplantation for Hodgkin lymphoma or non-Hodgkin lymphoma and targeted sequencing on cryopreserved aliquots of autologous stem-cell products from 401 patients who underwent ASCT for non-Hodgkin lymphoma between 2003 and 2010. We assessed the effect of CHIP at the time of ASCT on subsequent outcomes, including TMN, cause-specific mortality, and overall survival. Results For six of 12 patients in the exome sequencing cohort, mutations found in the TMN specimen were also detectable in the pre-ASCT specimen. In the targeted sequencing cohort, 120 patients (29.9%) had CHIP at the time of ASCT, which was associated with an increased rate of TMN (10-year cumulative incidence, 14.1% v 4.3% for those with and without CHIP, respectively; P = .002). Patients with CHIP had significantly inferior overall survival compared with those without CHIP (10-year overall survival, 30.4% v 60.9%, respectively; P < .001), including increased risk of death from TMN and cardiovascular disease. Conclusion In patients undergoing ASCT for lymphoma, CHIP at the time of transplantation is associated with inferior survival and increased risk of TMN.