Providing 0.1 Full-Time Equivalent (FTE) Support to Fellowship Core Faculty Improves Faculty Involvement in Fellowship Education and Recruitment

In 2022, the American Council for Graduate Medical Education (ACGME) recommended that core faculty (CF) in medical subspecialty fellowships receive at least 0.1 full-time equivalent (FTE) salary support, with plans to enforce compliance in July 2023. After early feedback raised concerns about potential unintended consequences, ACGME deferred enforcement to July 2024. Hence, there is an urgent need to understand the ramifications of providing FTE support for CF. In 2020, the Yale hematology and medical oncology (HO) fellowship program began providing 0.1 FTE support to all CF. Perceptions regarding this were assessed via surveys distributed to all CF in 2021 and 2022 and to all HO fellows in 2021. The vast majority (83.3%) of CF survey respondents reported improved job satisfaction and an increased sense of involvement in the fellowship program as a result of the new 0.1 FTE-supported CF program. Most CF increased attendance at fellowship conferences, devoted more time to mentorship, and increased participation in recruitment. In free text comments, CF respondents described that providing 0.1 FTE support made them "feel rewarded," gave them "a sense of commitment" to the fellowship, and helped "offset clinical requirements." HO fellows reported "a positive impact" of the new program with faculty being "more present at lectures." The median number of times faculty were available to interview fellowship applicants rose markedly after introduction of the program. The FTE-supported CF program was viewed enthusiastically by fellows and faculty, resulting in increased CF involvement in fellowship education and recruitment.

CD70-Targeted Allogeneic CAR T-Cell Therapy for Advanced Clear Cell Renal Cell Carcinoma

Therapeutic approaches for clear cell renal cell carcinoma (ccRCC) remain limited; however, chimeric antigen receptor (CAR) T-cell therapies may offer novel treatment options. CTX130, an allogeneic CD70-targeting CAR T-cell product, was developed for the treatment of advanced or refractory ccRCC. We report that CTX130 showed favorable preclinical proliferation and cytotoxicity profiles and completely regressed RCC xenograft tumors. We also report results from 16 patients with relapsed/refractory ccRCC who received CTX130 in a phase I, multicenter, first-in-human clinical trial. No patients encountered dose-limiting toxicity, and disease control was achieved in 81.3% of patients. One patient remains in a durable complete response at 3 years. Finally, we report on a next-generation CAR T construct, CTX131, in which synergistic potency edits to CTX130 confer improved expansion and efficacy in preclinical studies. These data represent a proof of concept for the treatment of ccRCC and other CD70+ malignancies with CD70-targeted allogeneic CAR T cells.

SIGNIFICANCE

Although the role of CAR T cells is well established in hematologic malignancies, the clinical experience in solid tumors has been disappointing. This clinical trial demonstrates the first complete response in a patient with RCC, reinforcing the potential benefit of CAR T cells in the treatment of solid tumors.

Area Vulnerability and Disparities in Therapy for Patients With Metastatic Renal Cell Carcinoma

Importance

Area-level measures of sociodemographic disadvantage may be associated with racial and ethnic disparities with respect to receipt of treatment for metastatic renal cell carcinoma (mRCC) but have not been investigated previously, to our knowledge.

Objective

To assess the association between area-level measures of social vulnerability and racial and ethnic disparities in the treatment of US Medicare beneficiaries with mRCC from 2015 through 2019.

Design, Setting, and Participants

This retrospective cohort study included Medicare beneficiaries older than 65 years who were diagnosed with mRCC from January 2015 through December 2019 and were enrolled in fee-for-service Medicare Parts A, B, and D from 1 year before through 1 year after presumed diagnosis or until death. Data were analyzed from November 22, 2022, through January 26, 2024.

Exposures

Five different county-level measures of disadvantage and 4 zip code-level measures of vulnerability or deprivation and segregation were used to dichotomize whether an individual resided in the most vulnerable quartile according to each metric. Patient-level factors included age, race and ethnicity, sex, diagnosis year, comorbidities, frailty, Medicare and Medicaid dual enrollment eligibility, and Medicare Part D low-income subsidy (LIS).

Main Outcomes and Measures

The main outcomes were receipt and type of systemic therapy (oral anticancer agent or immunotherapy from 2 months before to 1 year after diagnosis of mRCC) as a function of patient and area-level characteristics. Multivariable regression analyses were used to adjust for patient factors, and odds ratios (ORs) from logistic regression and relative risk ratios (RRRs) from multinomial logistic regression are reported.

Results

The sample included 15 407 patients (mean [SD] age, 75.6 [6.8] years), of whom 9360 (60.8%) were men; 6931 (45.0%), older than 75 years; 93 (0.6%), American Indian or Alaska Native; 257 (1.7%), Asian or Pacific Islander; 757 (4.9%), Hispanic; 1017 (6.6%), non-Hispanic Black; 12 966 (84.2%), non-Hispanic White; 121 (0.8%), other; and 196 (1.3%), unknown. Overall, 8317 patients (54.0%) received some type of systemic therapy. After adjusting for individual factors, no county or zip code-level measures of social vulnerability, deprivation, or segregation were associated with disparities in treatment. In contrast, patient-level factors, including female sex (OR, 0.78; 95% CI, 0.73-0.84) and LIS (OR, 0.48; 95% CI, 0.36-0.65), were associated with lack of treatment, with particularly limited access to immunotherapy for patients with LIS (RRR, 0.25; 95% CI, 0.14-0.43). Associations between individual-level factors and treatment in multivariable analysis were not mediated by the addition of area-level metrics. Disparities by race and ethnicity were consistently and only observed within the most vulnerable areas, as indicated by the top quartile of each vulnerability deprivation index.

Conclusions and Relevance

In this cohort study of older Medicare patients diagnosed with mRCC, individual-level demographics, including race and ethnicity, sex, and income, were associated with receipt of systemic therapy, whereas area-level measures were not. However, individual-level racial and ethnic disparities were largely limited to socially vulnerable areas, suggesting that efforts to improve racial and ethnic disparities may be most effective when targeted to socially vulnerable areas.

Personalizing approaches to the management of metastatic hormone sensitive prostate cancer: role of advanced imaging, genetics and therapeutics

PURPOSE

To summarize contemporary and emerging strategies for the diagnosis and management of metastatic hormone sensitive prostate cancer (mHSPC), focusing on diagnostic testing and therapeutics.

METHODS

Literature review using PUBMED-Medline databases as well as clinicaltrials.gov to include reported or ongoing clinical trials on treatment for mHSPC. We prioritized the findings from phase III randomized clinical trials, systematic reviews, meta-analyses and clinical practice guidelines.

RESULTS

There have been significant changes to the diagnosis and staging evaluation of mHSPC with the integration of increasingly accurate positron emission tomography (PET) imaging tracers that exceed the performance of conventional computerized tomography (CT) and bone scan. Germline multigene testing is recommended for the evaluation of patients newly diagnosed with mHSPC given the prevalence of actionable alterations that may create candidacy for specific therapies. Although androgen deprivation therapy (ADT) remains the backbone of treatment for mHSPC, approaches to first-line treatment include the integration of multiple agents including androgen receptor synthesis inhibitors (ARSI; abiraterone) Androgen Receptor antagonists (enzalutamide, darolutamide, apalautamide), and docetaxel chemotherapy. The combination of ADT, ARSI, and docetaxel chemotherapy has recently been evaluated in a randomized trial and was associated with significantly improved overall survival including in patients with a high burden of disease. The role of local treatment to the prostate with radiation has been evaluated in randomized trials with additional studies underway evaluating the role of cytoreductive radical prostatectomy.

CONCLUSION

The staging and initial management of patients with mHSPC has undergone significant advances in the last decade with advancements in the diagnosis, treatment and sequencing of therapies.

Disparities in immune and targeted therapy utilization for older US patients with metastatic renal cell carcinoma

Disparities in metastatic renal cell carcinoma (mRCC) outcomes persist in the era of oral anticancer agents (OAAs) and immunotherapies (IOs). We examined variation in the utilization of mRCC systemic therapies among US Medicare beneficiaries from 2015 to 2019. Logistic regression models evaluated the association between therapy receipt and demographic covariates including patient race, ethnicity, and sex. In total, 15 407 patients met study criteria. After multivariable adjustment, non-Hispanic Black race and ethnicity was associated with reduced IO (adjusted relative risk ratio [aRRR] = 0.76, 95% confidence interval [CI] = 0.61 to 0.95; P = .015) and OAA receipt (aRRR = 0.76, 95% CI = 0.64 to 0.90; P = .002) compared with non-Hispanic White race and ethnicity. Female sex was associated with reduced IO (aRRR = 0.73, 95% CI = 0.66 to 0.81; P < .001) and OAA receipt (aRRR = 0.74, 95% CI = 0.68 to 0.81; P < .001) compared with male sex. Thus, disparities by race, ethnicity, and sex were observed in mRCC systemic therapy utilization for Medicare beneficiaries from 2015 to 2019.

Examination of resistance to nivolumab monotherapy through single-cell analysis of tumors from patients enrolled in the HCRN GU16-260 study of nivolumab monotherapy

698

Background: Nivolumab (nivo) monotherapy demonstrated anti-tumor activity in treatment-naïve renal cell carcinoma (RCC) in Part A of HCRN GU16-260 across all IMDC groups and in multiple histologies. Patient tumor samples were collected to characterize the tumor-immune microenvironmental (TME) determinants of effective anti-tumor immunity with nivo. Methods: Eligible patients (with clear cell or non-clear cell histology) underwent tumor biopsy prior to and/or at resistance to nivo monotherapy. Fresh tissue fragments were cryopreserved locally and centrally processed to extract viable single-cells from the RCC TME. Single-cell RNA-sequencing (scRNA-seq) and T cell receptor (TCR)-sequencing (scTCR-seq) was performed on all tumor samples. Gene expression signatures discovered through scRNA-seq were used to interrogate previously published bulk transcriptomic data from the CheckMate-009/010/025 trials of nivo in the treatment-refractory setting. Results: In total, 72,730 viable single-cells (56,900 immune and 15,830 tumor or stromal cells) were sequenced from 17 patients (8 with baseline only, 7 with progression only, and 2 with paired baseline and progression samples) across 7 trial sites. Trajectory inference analysis of tumor-infiltrating T cells revealed a bifurcating trajectory, starting with naïve T cells and ending either in PMCH+ terminally exhausted CD8+ T cells or SLAMF7+ CD8+ T cells. Notably, the SLAMF7+ T cell population expressed high levels of cytotoxic genes (including GZMA, GZMB, GNLY) and markers of tissue residency ( ZNF683/HOBIT and ITGAE/CD103), and had a restricted TCR diversity (normalized Shannon index = 0.57). Among patients with at least 100 sequenced T cells (n = 14), a higher percentage of SLAMF7+ CD8+ T cells (relative to total T cells) was associated with primary resistance (progressive disease [PD] as best response) to nivo (mean percentage in PD [n = 4] patients 32.7%; stable disease [n = 4] patients, 9.1%; complete or partial response [CR/PR; n = 6] patients, 2.2%; p = 0.019 for CR/PR vs PD). A signature derived using genes expressed in the T cell trajectory branch containing the SLAMF7+ CD8+ T cell population was used to interrogate bulk RNA-seq data from 172 pre-treatment tumors from the nivo arms of the CheckMate-009/010/025 trials. The signature score was enriched in patients with PD compared to CR/PR as best response (p = 0.032). Analysis of bulk whole exome sequencing and RNA-seq from patients enrolled in the HCRN GU16-260 is pending. Conclusions: Single-cell transcriptomic analysis uncovered a SLAMF7+ CD8 + T cell population with markers of cytotoxicity and tissue residency that was associated with resistance to nivo monotherapy in RCC. Further, the study highlights that scRNA-seq is a viable scientific strategy for deep correlative analysis in multicenter clinical trials.

Treatment-free survival (TFS) outcomes from the phase II study of nivolumab and salvage nivolumab + ipilimumab in advanced clear cell renal cell carcinoma (aRCC) (HCRN GU16-260-Cohort A)

604

Background: Treatment with immunotherapy can be associated with prolonged disease control after discontinuation without the need for further anticancer therapy. Toxicity from therapy can also persist after cessation. TFS with and without toxicity can characterize survival time. Significant TFS was reported for CheckMate 067 trial in pts with metastatic melanoma (Regan et al JITC 2021) and CheckMate 214 trial for pts with aRCC (Regan et al CCR 2021), but treatment was often halted for toxicity rather than a pre-defined treatment endpoint. We therefore sought to assess TFS in the HCRN GU16 260 trial, which was designed to reduce toxicity and to cap immunotherapy duration (Atkins et al JCO 2022). Methods: Data were analyzed from 128 patients (pts) with clear-cell aRCC treated with first-line nivolumab (NIVO) monotherapy for up to 2 years. As part of the protocol, salvage nivolumab/ipilimumab (NIVO/IPI) for up to 1 year was provided to eligible patients with disease progression at any point or stable disease at 48 weeks (28% of pts). TFS was defined as the area between Kaplan-Meier curves for time from registration to protocol therapy cessation and for time from registration to subsequent therapy initiation or death, estimated from 36-month (mo) mean times. The time on treatment or off treatment with grade 3+ treatment-related adverse events (TRAEs) was also captured. Results: At 36 mos from enrollment, 68.3% of pts were alive: 96.8% of IMDC favorable-risk (FAV) pts and 56.6% of those with intermediate/poor-risk (I/P), respectively. The 36-mo mean time on protocol therapy was 11.5 mos (16.0 mos for FAV pts and 9.6 mos for I/P pts). The 36-mo mean TFS for the whole population was 9.4 mos. For FAV pts the mean TFS was 12.9 mos, of which TFS with grade 3+ TRAEs was 1.5 mos. For I/P pts, the mean TFS was 8.0 mos, of which TFS with grade 3+ TRAEs was 1.0 mos. At 36 mos, 65.6% of FAV pts and 27.1% of I/P pts were alive and second-line treatment-free. Conclusions: NIVO monotherapy with salvage NIVO/IPI in non-responders is an active treatment approach in treatment-naïve pts with aRCC and results in substantial TFS and toxicity-free TFS. TFS was particularly noted in pts with FAV disease, further supporting the use of an immunotherapy-only regimen in this population. Clinical trial information: NCT03117309 . [Table: see text]

Evolution of systemic therapy from 2015 to 2019 for older patients in the United States with metastatic renal cell carcinoma

610

Background: Immune checkpoint inhibitors (IOs) and oral anti-cancer agents (OAAs) have demonstrated survival improvements in randomized trials of patients with metastatic renal cell carcinoma (mRCC). IOs were approved as second-line mRCC therapy in 2015 (nivolumab), followed by first-line approval in 2018 (ipilimumab/nivolumab). Real-world changes in overall treatment rates and IO usage have not been examined in patients over 65, who are often underrepresented in trials. Disparities in mRCC outcomes have persisted in the era of these novel therapies, raising the question of whether receipt of IOs and OAAs varies by race and ethnicity. Methods: We conducted a retrospective cohort study of Medicare beneficiaries over age 65 diagnosed with mRCC from 2015 through 2019 who were enrolled in fee-for-service Medicare Parts A, B, and D from 1 year prior to diagnosis through 1 year after presumed diagnosis or until death. We identified our cohort using diagnosis codes for primary or secondary kidney malignancy. We queried claims from 2014-2020, identifying receipt of IO, OAA, or other systemic therapies in the 2 months before through 1 year after diagnosis. Patients that received both IOs and OAAs were categorized as IO if both therapies were started within 60 days; otherwise, patients were categorized by the first therapy received. We assessed trends in treatment from 2015-2019, stratifying by race and ethnicity to compare non-Hispanic White (NHW) patients with Hispanic, Black, Asian, Pacific Islander, American Indian, Native Alaskan, or Other patients (grouped as non-NHW due to limited sample sizes). Results: We identified 15,407 patients who were diagnosed with mRCC between 2015-2019 and met study criteria. Non-Hispanic White patients comprised 84% of our sample. Receipt of IOs increased from 4% of patients in 2015 to 37% in 2019 ( P < .001). Among NHW patients, IO treatment receipt increased from 4% in 2015 to 38% in 2019 ( P < .001); for non-NHW patients, IO receipt grew from 3% in 2015 to 31% in 2019 ( P < .001). OAA usage decreased over time, from 31% of all patients in 2015 to 11% in 2019 ( P < .001). The percent of NHW patients treated with any systemic therapy increased from 51% in 2015 to 60% in 2019 ( P < .001), while there was no significant change for non-NHW patients (51% in 2015 to 54% in 2019; P = 0.27). Conclusions: Among Medicare beneficiaries, receipt of IO therapy for mRCC increased from 2015-2019. Receipt of any systemic therapy significantly increased over time for NHW patients, but not for non-NHW patients. [Table: see text]

Translation of the 27-gene immuno-oncology test (IO score) to predict outcomes in immune checkpoint inhibitor treated metastatic urothelial cancer patients

BACKGROUND

The IO Score is a 27-gene immuno-oncology (IO) classifier that has previously predicted benefit to immune checkpoint inhibitor (ICI) therapy in triple negative breast cancer (TNBC) and non-small cell lung cancer (NSCLC). It generates both a continuous score and a binary result using a defined threshold that is conserved between breast and lung. Herein, we aimed to evaluate the IO Score's binary threshold in ICI-naïve TCGA bladder cancer patients (TCGA-BLCA) and assess its clinical utility in metastatic urothelial cancer (mUC) using the IMvigor210 clinical trial treated with the ICI, atezolizumab.

METHODS

We identified a list of tumor immune microenvironment (TIME) related genes expressed across the TCGA breast, lung squamous and lung adenocarcinoma cohorts (TCGA-BRCA, TCGA-LUSQ, and TCGA-LUAD, 939 genes total) and then examined the expression of these 939 genes in TCGA-BLCA, to identify patients as having high inflammatory gene expression. Using this as a test of classification, we assessed the previously established threshold of IO Score. We then evaluated the IO Score with this threshold in the IMvigor210 cohort for its association with overall survival (OS).

RESULTS

In TCGA-BLCA, IO Score positive patients had a strong concordance with high inflammatory gene expression (p < 0.0001). Given this concordance, we applied the IO Score to the ICI treated IMvigor210 patients. IO Score positive patients (40%) had a significant Cox proportional hazard ratio (HR) of 0.59 (95% CI 0.45-0.78 p < 0.001) for OS and improved median OS (15.6 versus 7.5 months) compared to IO Score negative patients. The IO Score remained significant in bivariate models combined with all other clinical factors and biomarkers, including PD-L1 protein expression and tumor mutational burden.

CONCLUSION

The IMvigor210 results demonstrate the potential for the IO Score as a clinically useful biomarker in mUC. As this is the third tumor type assessed using the same algorithm and threshold, the IO Score may be a promising candidate as a tissue agnostic marker of ICI clinical benefit. The concordance between IO Score and inflammatory gene expression suggests that the classifier is capturing common features of the TIME across cancer types.

Bempegaldesleukin plus nivolumab in first-line renal cell carcinoma: results from the PIVOT-02 study

Background

Immune checkpoint inhibitor-based combinations have expanded the treatment options for patients with renal cell carcinoma (RCC); however, tolerability remains challenging. The aim of this study was to evaluate the safety and efficacy of the immunostimulatory interleukin-2 cytokine prodrug bempegaldesleukin (BEMPEG) plus nivolumab (NIVO) as first-line therapy in patients with advanced clear-cell RCC.

Methods

This was an open-label multicohort, multicenter, single-arm phase 1/2 study; here, we report results from the phase 1/2 first-line RCC cohort (N=49). Patients received BEMPEG 0.006 mg/kg plus NIVO 360 mg intravenously every 3 weeks. The primary objectives were safety and objective response rate (ORR; patients with measurable disease at baseline and at least one postbaseline tumor response assessment). Secondary objectives included overall survival (OS) and progression-free survival (PFS). Exploratory biomarker analyses: association between baseline biomarkers and ORR.

Results

At a median follow-up of 32.7 months, the ORR was 34.7% (17/49 patients); 3/49 patients (6.1%) had a complete response. Of the 17 patients with response, 14 remained in response for >6 months, and 6 remained in response for >24 months. Median PFS was 7.7 months (95% CI 3.8 to 13.9), and median OS was not reached (95% CI 37.3 to not reached). Ninety-eight per cent (48/49) of patients experienced ≥1 treatment-related adverse event (TRAE) and 38.8% (19/49) had grade 3/4 TRAEs, most commonly syncope (8.2%; 4/49) and increased lipase (6.1%; 3/49). No association between exploratory biomarkers and ORR was observed. Limitations include the small sample size and single-arm design.

Conclusions

BEMPEG plus NIVO showed preliminary antitumor activity as first-line therapy in patients with advanced clear-cell RCC and was well tolerated. These findings warrant further investigation.

Phase II study of nivolumab and salvage nivolumab + ipilimumab in treatment-naïve patients (pts) with advanced clear cell renal cell (HCRN GU16-260-Cohort A): Final report

288

Background: Nivolumab (nivo) is FDA approved for patients (pts) with VEGFR TKI-resistant RCC and the nivo + ipilimumab (nivo/ipi) combination is FDA approved for treatment naïve pts with IMDC intermediate and poor risk renal cell carcinoma (RCC). Little information was available on the efficacy and toxicity of nivo monotherapy in treatment naïve RCC or the efficacy of nivo/ipi salvage in pts with tumors resistant to initial nivo monotherapy. Methods: Eligible pts with treatment naïve RCC received nivo 240mg IV q2 wk x 6 doses followed by 360mg IV q3 wk x 4 doses followed by 480 mg q4 wk until progressive disease (PD), toxicity, or completion of 96 wks of treatment (Part A). Pts with PD prior to, or stable disease (SD) at 48 wks (pSD) were potentially eligible to receive salvage nivo (3mg/kg)/ipi (1 mg/kg) q3 wk x 4 doses followed by q4 wk nivo maintenance for up to 48 wks (Part B). All pts were required to submit tissue from a metastatic lesion obtained within 12 months (mos) prior to study entry and prior to Part B for correlative studies. Results: 123 pts with clear cell(cc) RCC were enrolled between 5/2017 and 12/2019 at 12 participating HCRN sites. Data lock was 04/07/2021. Median Follow-up 26.9 mos. Median age 65 (32-86) years; 72% male. IMDC risk: favorable (Fav) 35 (28%), intermediate (I) 76 (62%) and poor (P) 12 (10%). 22 (18%) had a component of sarcomatoid histology (SARC). RECIST defined ORR was: 34.1% (25.8-43.2%) (CR 6.5%, PR 27.6%), SD 47 (35.8%). ORR by irRECIST was 39%. ORR by IMDC was: Fav 20/35 (57.1%) (39-74%), (I/P) 22/88 (25%) and for SARC 36.4%. ORR by PD-L1 status was 21/78 (27%), 8/16 (50%) and 6/8 (75%) for pts with tumor PD-L1 of 0, 1-20 or > 20%, respectively (trend test p-value 0.002). 5/7 (71.4%) Fav pts with PD-L1 > 1 responded. Median DOR was 27.6 (13.7, NA) mos with 26/42 responders including 17/20 (85%) with Fav Risk remaining progression free. Median PFS was 8.2 (5.5, 10.9) mos; (30.3 for IMDC Fav and 5.4 for I/P). 91 pts remain alive with 24 mos OS rate of 78%. 65 patients (59 PD, 6 pSD) were potentially eligible for salvage nivo/ipi (Part B), but 25 did not enroll due to symptomatic PD (6), grade 3-4 toxicity on nivo (17), or other (2) and 5 were not treated due to inability to confirm residual disease on a biopsy. ORR for Part B by RECIST was 11.4% (4/35) and by irRECIST 17.2%. Grade 3-5 treatment-related AEs (TrAE) (not including asymptomatic amylase/lipase) were seen in 20.3% in Part A and 14.2% in Part B with 1 death in each cohort. Conclusions: Nivo monotherapy is active in treatment naïve ccRCC across all IMDC groups. Although efficacy appears less than combination nivo/ipi in I/P pts, Fav pts had a notably high ORR and DOR. Efficacy appeared to correlate with tumor PD-L1 status, although at least half the responders had a tumor PD-L1 of 0. Salvage treatment with nivo/ipi after nivo was frequently not feasible and of limited benefit. Clinical trial information: NCT03117309.

Current Understanding and Management of Intraductal Carcinoma of the Prostate

PURPOSE OF REVIEW

This review will discuss current understanding and management approaches of Intraductal carcinoma of the prostate (IDC-P). IDC-P is a histological finding characterized by neoplastic cells that expand but do not invade prostate ducts.

RECENT FINDINGS

The presence of IDC-P on a prostate biopsy is almost always associated with an invasive disease component and is independently associated with worse clinical outcomes in both early and late disease. These tumors are enriched for mutations in homologous DNA recombination repair (HRR) leading to high genomic instability. Multiparametric MRI with targeted biopsy may aid in diagnosis. Given the poor clinical outcomes associated with this histologic entity, its presence in biopsies should warrant consideration of aggressive management.

Bempegaldesleukin Plus Nivolumab in First-Line Metastatic Melanoma

Therapies that produce deep and durable responses in patients with metastatic melanoma are needed. This phase II cohort from the international, single-arm PIVOT-02 study evaluated the CD122-preferential interleukin-2 pathway agonist bempegaldesleukin (BEMPEG) plus nivolumab (NIVO) in first-line metastatic melanoma.

Phase II study of nivolumab and salvage nivolumab + ipilimumab in treatment-naïve patients (pts) with advanced non-clear cell renal cell carcinoma (nccRCC) (HCRN GU16-260-Cohort B)

4510

Background: The HCRN GU16-260 trial reported on the efficacy and toxicity of nivo monotherapy in treatment naïve clear cell RCC (Cohort A) and the efficacy of nivo/ipi salvage therapy in pts with tumors resistant to initial nivo monotherapy (Atkins JCO 2020.38.15_suppl.5006). Limited information is available on the effects of such an approach in pts with advanced nccRCC. Methods: Eligible pts with treatment-naïve nccRCC received nivo 240mg IV q2 wk x 6 doses followed by 360mg IV q3 wk x 4 doses followed by 480 mg q4 wk until progressive disease (PD), toxicity, or completion of 96 wks of treatment (Part A). Pts with PD prior to or stable disease (SD) at 48 wks (pSD) were potentially eligible to receive salvage nivo (3mg/kg) /ipi (1 mg/kg) q3 wk x 4 doses followed by q4 wk nivo maintenance for up to 48 wks (Part B). All pts were required to submit tissue from a metastatic lesion obtained within 12 months (mo) prior to study entry and prior to enrolling on Part B for correlative studies. Results: 35 pts with nccRCC were enrolled between 5/2017 and 12/2019 at 12 participating HCRN sites. Median age 63 (range 35-84 years); 89% male. IMDC favorable 8 (23%), intermediate 18 (51%) and poor risk 9 (26%). Of the 35 pts 19 (54%) had papillary, 6 (17%) chromophobe and 10 (29%) unclassified histology. RECIST defined ORR was 5 of 35 (14.3%) [CR 2 (5.7%), PR 3 (8.6%)], SD 16 (45.7%), PD 14 (40.0%). Immune-related ORR was 8 of 35 (22.9%). RECIST ORR by histology was: papillary - 1/19 (5%); chromophobe - 1/6 (17%); unclassified - 3/10 (30%). 9 pts (26%) had tumors with sarcomatoid features with 3 (33%) (2 unclassified, 1 papillary) responding. Median PFS was 4.0 (2.7, 4.3) mo. 21 pts remain alive. None of the responders have progressed or died. 28 pts (25 PD, 3 pSD) were potentially eligible for salvage nivo/ipi (Part B), but 12 did not enroll due to symptomatic PD (2), grade 3-4 toxicity on nivo (3), or other including no biopsy tissue (7). In the 16 Part B pts, best response to nivo/ipi was: PR (1, 6%) – (unclassified/non-sarcomatoid); SD (7, 44%); PD (8, 50%). Grade 3 Treatment-related adverse events (TrAEs) were seen in 7/35 (20%) on nivo. Grade 3-5 TrAEs were seen in 7/16 (44%) on nivo/ipi with 1 pt experiencing sudden death. Correlative studies including PD-L1 status, WES and RNAseq are pending. Conclusions: Nivo monotherapy has limited activity in treatment naïve nccRCC with most responses (4 of 5) seen in pts with sarcomatoid and/or unclassified tumors. Toxicity is consistent with prior nivo studies. Salvage treatment with nivo/ipi was provided in 16 of 28 (57%) pts with PD/pSD on nivo monotherapy, with 1 response observed. Clinical trial information: NCT03117309.

Renal sarcomas: Epidemiology, treatment and outcomes

362

Background: Renal sarcomas are a rare malignancy in adults and have been inadequately evaluated on a US national level regarding epidemiology, treatment, and outcomes. Methods: The 2004-2016 NCDB and SEER databases were queried for adult patients diagnosed with sarcomas of renal origin. Age-adjusted incidence rates were derived from the SEER database. Overall survival (OS) was assessed using multivariable Cox proportional hazards models adjusting for demographics, tumor and treatment variables. Results: 1,279 renal sarcomas comprising 39 subtypes were reported from 2004-2016, contributing 0.3% of all NCDB renal malignancies. As shown in the table below, the most common subtypes were leiomyosarcoma (LMS), angiosarcoma (AS), malignant rhabdoid tumor (MRT), dedifferentiated liposarcoma (DL) and primitive neuroectodermal tumors (PNET). Over the study period, renal sarcoma incidence rates remained constant at 0.5 cases / 1 million citizens. Sex-specific incidence differences were evident with female predominance for LMS, and male predominance for AS. Age at diagnosis and tumor diameter varied according to sarcoma subtypes: for example, median age in LMS was 62y compared to 30y in Ewing sarcoma patients; median tumor diameter was 18cm for solitary fibrous tumors and 7.5cm for synovial sarcoma. Renal sarcoma was staged as T3 in 33.3% and T4 in 14.2%, while distant metastases were evident in 29.1% of cases at diagnosis. Most T1-T3 stage renal sarcomas underwent surgical resection (992/1098, 84%), compared to 71% for T4 renal sarcomas (128/181). Systemic therapy was administered in 32.1% of renal sarcoma cases (23.5% combined with surgical resection). Renal sarcoma 1-,2-, and 5-year OS rates were 48%, 24%, and 13%. OS was worse for T4 vs T1-3 sarcomas (HR=1.6, p<0.001), and cases with distant metastases vs none (HR=3.2, p<0.001). As summarized in the table, OS varied according to sarcoma subtypes with worse OS for AS compared to PNET (HR=1.5, p=0.04). Conclusions: Accounting for 0.3% of renal malignancies in adults, renal sarcomas include 39 different histological subtypes with distinct demographics, tumor parameters and outcomes. Renal sarcomas commonly present with advanced T stage at diagnosis and are treated with surgical resection with or without systemic therapy. [Table: see text]

Integration of Genomic Medicine in Pathology Resident Training

OBJECTIVES

To assess current pathology resident training in genomic and molecular pathology.

METHODS

The Training Residents in Genomics (TRIG) Working Group has developed survey questions for the pathology Resident In-Service Examination (RISE) since 2012. Responses to these questions, as well as knowledge questions, were analyzed.

RESULTS

A total of 2,529 residents took the 2019 RISE. Since 2013, there has been an increase in postgraduate year 4 (PGY4) respondents indicating training in genomic medicine (58% to approximately 80%) but still less than almost 100% each year for molecular pathology. In 2019, PGY4 residents indicated less perceived knowledge and ability related to both genomic and traditional molecular pathology topics compared with control areas. Knowledge question results supported this subjective self-appraisal.

CONCLUSIONS

The RISE is a powerful tool for assessing the current state and also trends related to resident training in genomic pathology. The results show progress but also the need for improvement in not only genomic pathology but traditional molecular pathology training as well.

Bempegaldesleukin (NKTR-214) plus Nivolumab in Patients with Advanced Solid Tumors: Phase I Dose-Escalation Study of Safety, Efficacy, and Immune Activation (PIVOT-02)

This single-arm, phase I dose-escalation trial (NCT02983045) evaluated bempegaldesleukin (NKTR-214/BEMPEG), a CD122-preferential IL2 pathway agonist, plus nivolumab in 38 patients with selected immunotherapy-naïve advanced solid tumors (melanoma, renal cell carcinoma, and non-small cell lung cancer). Three dose-limiting toxicities were reported in 2 of 17 patients during dose escalation [hypotension (n = 1), hyperglycemia (n = 1), metabolic acidosis (n = 1)]. The most common treatment-related adverse events (TRAE) were flu-like symptoms (86.8%), rash (78.9%), fatigue (73.7%), and pruritus (52.6%). Eight patients (21.1%) experienced grade 3/4 TRAEs; there were no treatment-related deaths. Total objective response rate across tumor types and dose cohorts was 59.5% (22/37), with 7 complete responses (18.9%). Cellular and gene expression analysis of longitudinal tumor biopsies revealed increased infiltration, activation, and cytotoxicity of CD8⁺ T cells, without regulatory T-cell enhancement. At the recommended phase II dose, BEMPEG 0.006 mg/kg plus nivolumab 360 mg every 3 weeks, the combination was well tolerated and demonstrated encouraging clinical activity irrespective of baseline PD-L1 status. SIGNIFICANCE: These data show that BEMPEG can be successfully combined with a checkpoint inhibitor as dual immunotherapy for a range of advanced solid tumors. Efficacy was observed regardless of baseline PD-L1 status and baseline levels of tumor-infiltrating lymphocytes, suggesting therapeutic potential for patients with poor prognostic risk factors for response to PD-1/PD-L1 blockade.See related commentary by Rouanne et al., p. 1097.This article is highlighted in the In This Issue feature, p. 1079.

Phase II study of nivolumab and salvage nivolumab + ipilimumab in treatment-naïve patients (pts) with advanced renal cell carcinoma (RCC) (HCRN GU16-260)

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Background: Nivolumab (nivo) is FDA approved for pts with VEGFR TKI-resistant RCC and the nivo + ipilimumab (nivo/ipi) combination is FDA approved for treatment naïve pts with IMDC intermediate and poor risk RCC. Little information is available on the efficacy and toxicity of nivo monotherapy in treatment naïve RCC or the efficacy of nivo/ipi salvage therapy in pts with tumors resistant to initial nivo monotherapy. Methods: Eligible pts with treatment naïve RCC received nivo 240mg IV q2 wk x 6 doses followed by 360mg IV q3 wk x 4 doses followed by 480 mg q4 wk until progressive disease (PD), toxicity, or completion of 96 wks of treatment (Part A). Pts with PD prior to or stable disease (SD) at 48 wks (pSD) were potentially eligible to receive salvage nivo (3mg/kg) /ipi (1 mg/kg) q3 wk x 4 doses followed by q4 wk nivo maintenance for up to 48 wks (Part B). All pts were required to submit tissue from a metastatic lesion obtained within 12 months (mo) prior to study entry and prior to Part B. Pathology specimens will be analyzed by immunohistochemistry, quantitative immunofluorescence, WES and RNAseq with results linked to clinical outcome. Results: 123 pts with clear cell(cc) RCC were enrolled between 5/2017 and 12/2019 at 12 participating HCRN sites. Median age 65 (range 32-86 years); 72% male. IMDC favorable 30 (25%), intermediate 79 (65%) and poor risk 12 (10%). 22 (18%) had a component of sarcomatoid histology (SARC). 117 pts are currently evaluable for response. RECIST defined ORR was: 34 (29.3%)[CR 5 (4.3%), PR 29 (24.8%)], SD 47 (40.2%), PD 36 (30.7%). ORR by irRECIST was 35%. ORR by IMDC was: favorable 12/29 (41.4%), intermediate/poor 22/87 (25.3%) and for SARC 6/22 (27.3%). Median DOR is 13.8 (10.9, NA) mo. Median PFS is 7.4 (5.5, 10.9) mo. 110 pts remain alive. 60 pts (54 PD, 6 pSD) to date were potentially eligible for salvage nivo/ipi (Part B), but 28 did not enroll due to symptomatic PD (17), grade 3-4 toxicity on nivo (8), other (3). 27 of 32 Part B pts are currently evaluable for efficacy and 30 for toxicity. Best response to nivo/ipi was PR (11%), SD (30%), PD (59%). ORR by irRECIST was 19%. Grade 3-5 Treatment-related AEs (TrAE) were seen in 35/123 (28)% on nivo with 1 death due to respiratory failure. Grade 3-4 TrAE were seen in 10/30 (33%) on nivo/ipi with 0 deaths. Correlative studies are pending. Conclusions: Nivo monotherapy is active in treatment naïve ccRCC across all IMDC groups. Toxicity is consistent with prior nivo studies. Salvage treatment with nivo/ipi after nivo monotherapy was feasible in 53% of pts with PD/pSD, with 11% responding. Clinical trial information: NCT03117309 .

Association of cytoreductive nephrectomy and survival in the immune checkpoint inhibitor era

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Background: Cytoreductive nephrectomy (CN) for patients (pts) with metastatic renal cell carcinoma (mRCC) improved overall survival (OS) in the interferon (IFN) era, but the benefit of CN in the immune checkpoint inhibitor (ICI) era is unknown. Methods: We identified pts with mRCC receiving immunotherapy (IT) from 2004-2015 in the National Cancer Database (NCDB). Pts with partial nephrectomy or ablation were excluded. The ICI era was defined as 2013-2015 based on a high-profile publication in 2012 demonstrating efficacy of ICI in mRCC and the IFN era was defined as 2004-2005 due to FDA approval of sorafenib in 12/2005. Pts receiving CN with TKI were excluded, as prior NCDB study showed an OS benefit to CN in contrast to the results of the CARMENA trial. Univariable (UVA) and multivariable (MVA) associates with OS during each era were identified using Cox regression analysis including age, sex, race, income, insurance, treatment facility type, treatment location, clinical T stage (cT), clinical N stage (cN), histology, Fuhrman grade (FG), other metastectomy, and CN. Results: There was a 65% decline in mRCC pts receiving IT from 2005 to 2006 (end of the IFN era), which remained low (11% rise from 2006-2012) until a 93% rise from 2012 to 2013 (start of the ICI era). 128 of 422 (30.3%) pts in the IFN era received CN compared to 218 of 526 (41.4%) patients in the ICI era, p<0.001. Pts in each era were balanced with respect to median age, race, income, location, cT, and histology, but the ICI era had higher proportions of pts with private insurance, treatment at an academic center, N0 disease, FG 3-4, and other metastatectomy (p<0.05). Most pts with CN in the ICI era had IT after CN (89.9%); this was not coded in the IFN era. In the IFN era, CN compared to IT alone was associated with improved OS on UVA (HR 0.59, 95% CI 0.47-0.73, p<0.001) and MVA (HR 0.62, 95% CI 0.47-0.83, p=0.001). In the ICI era, CN compared to IT alone was associated with improved OS on UVA (HR 0.63, 95% CI 0.49-0.81, p<0.001) but not on MVA (0.82, 95% CI 0.58-1.14, p=0.234). Conclusions: Despite increased utilization of CN for US pts with mRCC treated with IT during the ICI era, the lack of OS benefit in recent years suggests a need for prospective reevaluation of the value CN and its timing with ICI.

Bempegaldesleukin selectively depletes intratumoral Tregs and potentiates T cell-mediated cancer therapy

High dose interleukin-2 (IL-2) is active against metastatic melanoma and renal cell carcinoma, but treatment-associated toxicity and expansion of suppressive regulatory T cells (Tregs) limit its use in patients with cancer. Bempegaldesleukin (NKTR-214) is an engineered IL-2 cytokine prodrug that provides sustained activation of the IL-2 pathway with a bias to the IL-2 receptor CD122 (IL-2Rβ). Here we assess the therapeutic impact and mechanism of action of NKTR-214 in combination with anti-PD-1 and anti-CTLA-4 checkpoint blockade therapy or peptide-based vaccination in mice. NKTR-214 shows superior anti-tumor activity over native IL-2 and systemically expands anti-tumor CD8⁺ T cells while inducing Treg depletion in tumor tissue but not in the periphery. Similar trends of intratumoral Treg dynamics are observed in a small cohort of patients treated with NKTR-214. Mechanistically, intratumoral Treg depletion is mediated by CD8⁺ Teff-associated cytokines IFN-γ and TNF-α. These findings demonstrate that NKTR-214 synergizes with T cell-mediated anti-cancer therapies.

Interleukin-2 can induce an anti-tumour response, but is associated with toxicity. Here, the authors demonstrate that an engineered interleukin-2 promotes intratumoral T regulatory cell depletion while enhancing effective anti-tumour CD8⁺ T cell responses that result in potent tumor suppression.

Key Factors in Clinical Protocols for Adoptive Cell Therapy in Melanoma

Adoptive cell therapy (ACT) with autologous tumor infiltrating lymphocytes (TIL) has been studied for patients with advanced metastatic cancers (primarily melanoma) for decades and has changed significantly during that period. Treatment with TIL includes ex vivo cell activation and expansion followed by re-infusion of these cells into the patient. After cell infusion, patients receive Interleukin-2 (IL-2). Objective response rates up to 52% have been seen in patients with metastatic melanoma. Efforts to improve TIL therapy include better selection and expansion of tumor-reactive lymphocytes, optimization of IL-2 or other T cell activating cytokine dosing, and, potentially, genetic manipulation of the immune cell product. Here we describe methods involved in the collection, expansion, and treatment with TIL for patients with metastatic melanoma.

A versatile flow-based assay for immunocyte-mediated cytotoxicity

Cell-mediated cytotoxicity is a critical function of the immune system in mounting defense against pathogens and cancers. Current methods that allow direct evaluation of cell-mediated cytotoxicity suffer from a wide-range of drawbacks. Here, we present a novel strategy to measure cytotoxicity that is direct, sensitive, rapid, and highly adaptable. Moreover, it allows accurate measurement of viability of both target and effector cells. Target cells are fluorescently labeled with a non-toxic, cell-permeable dye that covalently binds to cell proteins, including nuclear proteins. The labeled target cells are incubated with effector cells to begin killing. Following the killing reaction, the cell mixture is incubated with another dye that specifically stains proteins of dead cells, including nuclear proteins. In the final step, cell nuclei are released by Triton X-100, and analyzed by flow cytometry. This results in four nuclear staining patterns that separate target and effector nuclei as well as nuclei of live and dead cells. Analyzing nuclei, instead of cells, greatly reduces flow cytometry errors caused by the presence of target-effector cell aggregates. Target killing time can often be reduced to 2 h and the assay can be done in a high throughput format. We have successfully validated this assay in a variety of cytotoxicity scenarios including those mediated by NK-92 cells, Chimeric Antigen Receptor (CAR)-T cells, and Tumor Infiltrating Lymphocytes (TIL). Therefore, this technique is broadly applicable, highly sensitive and easily administered, making it a powerful tool to assess immunotherapy-based, cell-mediated cytotoxicity.

Baseline tumor-immune signatures associated with response to bempegaldesleukin (NKTR-214) and nivolumab

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Background: PIVOT-02 is an ongoing phase 1/2 study of bempegaldesleukin (NKTR-214), a CD122-preferential IL-2 pathway agonist, plus nivolumab in patients with advanced solid tumors. Bempegaldesleukin (NKTR-214) increases proliferative tumor infiltrating lymphocytes (TIL) and cell surface PD-1 on immune cells and PD-L1 on tumor cells, demonstrating potential synergy with anti-PD-1 therapy. Pre-treatment tumor biopsies from metastatic 1L melanoma (MEL) and urothelial carcinoma (UC) patients were analyzed to correlate baseline immune phenotype to response. Methods: Pre-treatment TIL (CD8+ T cells/mm2 and %CD3+ by IHC; 29 MEL; 22 UC) were measured and divided into high and low groups based on median values. PD-L1 (% PD-L1 on tumor cells by IHC [28-8 PharmDx]; 33 MEL; 23 UC) was scored negative (<1%) or positive (≥1%). Interferon gamma gene score (IFNG; 11 MEL) was scored as high or low based on median p value of <0.1 for 15 genes (EdgeSeq). High and low groups were correlated with responses per RECIST 1.1. Results: Baseline demographics and prognostic factors were balanced in the biomarker subgroups. Response rates for response evaluable MEL and UC were 53% (SITC 2018) and 48% (ASCO-GU 2019), respectively. In MEL, median values of CD3-TIL and CD8-TIL were 19% and 203 cells/mm2, respectively. Response rate correlations were 67% and 20% with IFNG high and low, 79% and 29% with CD3-TIL high and low, 79% and 33% with CD8-TIL high and low, and 68% and 43% with PD-L1 positive and negative. Most importantly, responses were observed in patients with the least favorable tumor microenvironment, characterized as both PD-L1 negative and TIL low, with responses of 17% (1/6 CD8-TIL), and 25% (2/8 CD3-TIL), respectively. Similar correlative trends were observed in UC, with 50% (4/8 CD8-TIL) and 38% (3/8 CD3-TIL) responses in patients with least favorable microenvironment. Conclusions: The biomarker program included in PIVOT-02 identified baseline immune signatures correlated with response for MEL and UC. The response rates observed in both the favorable and unfavorable tumor microenvironments indicate the potential of this combination and support its broad development. Clinical trial information: NCT02983045.

A First-in-Human Study and Biomarker Analysis of NKTR-214, a Novel IL2Rβγ-Biased Cytokine, in Patients with Advanced or Metastatic Solid Tumors

NKTR-214 (bempegaldesleukin) is a novel IL2 pathway agonist, designed to provide sustained signaling through heterodimeric IL2 receptor βγ to drive increased proliferation and activation of CD8⁺ T and natural killer cells without unwanted expansion of T regulatory cells (Treg) in the tumor microenvironment. In this first-in-human multicenter phase I study, NKTR-214 administered as an outpatient regimen was well tolerated and showed clinical activity including tumor shrinkage and durable disease stabilization in heavily pretreated patients. Immune activation and increased numbers of immune cells were observed in the periphery across all doses and cycles with no loss of NKTR-214 activity with repeated administration. On-treatment tumor biopsies demonstrated that NKTR-214 promoted immune cell increase with limited increase of Tregs. Transcriptional analysis of tumor biopsies showed that NKTR-214 engaged the IL2 receptor pathway and significantly increased genes associated with an effector phenotype. Based on safety and pharmacodynamic markers, the recommended phase II dose was determined to be 0.006 mg/kg every three weeks. SIGNIFICANCE: We believe that IL2- and IL2 pathway-targeted agents such as NKTR-214 are key components to an optimal immunotherapy treatment algorithm. Based on its biological activity and tolerability, NKTR-214 is being studied with approved immuno-oncology agents including checkpoint inhibitors.See related commentary by Sullivan, p. 694.This article is highlighted in the In This Issue feature, p. 681.

Current Status and Future Directions of Immunotherapy in Renal Cell Carcinoma

PURPOSE OF REVIEW

Renal cell carcinoma (RCC) was recognized as an immunologically sensitive cancer over 30 years ago. The first therapies to affect the course of RCC were cytokines (interferon alfa-2B and interleukin-2). Subsequently, drugs that inhibit HIF (hypoxia-inducible factor)/VEGF (vascular endothelial growth factor) signaling demonstrated overall survival advantages (tyrosine kinase inhibitors and mTor inhibitors).

RECENT FINDINGS

In the last 3 years, the immune checkpoint inhibitors (ICIs) have become the standard of care treatments in the first and second lines for RCC. Emerging data show that combinations of ICI, HIF signaling inhibitors, and cytokines are potentially powerful regimens. How to combine and sequence these types of therapies and how to integrate new approaches into the management of RCC are now the key questions for the field. Treatment of RCC is likely to change dramatically in the next few years.

Multicenter Phase 2 Trial of Gemcitabine, Carboplatin, and Sorafenib in Patients With Metastatic or Unresectable Transitional-Cell Carcinoma

BACKGROUND

Sorafenib, an oral tyrosine kinase inhibitor, may enhance the antitumor activity of platinum-based chemotherapy in transitional-cell carcinoma. This study investigated the safety and clinical outcome of adding sorafenib to gemcitabine and carboplatin for patients with advanced transitional-cell carcinoma.

PATIENTS AND METHODS

Subjects with metastatic or unresectable chemotherapy-naive TCC with Eastern Cooperative Oncology Group performance status 0 or 1 received gemcitabine (1000 mg/m² on days 1 and 8) and carboplatin (area under the curve of 5 on day 1) with sorafenib (400 mg 2 times a day on days 2-19 every 21 days) for 6 cycles. Subjects with stable disease or partial or complete response continued to receive sorafenib until disease progression. The primary end point was progression-free survival (PFS) at 5 months with a secondary end point of response (partial or complete).

RESULTS

Seventeen subjects were enrolled. The median number of cycles of gemcitabine and carboplatin with sorafenib provided was 4.4. A total of 15, 5, and 8 subjects required reductions of gemcitabine, carboplatin, and sorafenib, respectively. Thirteen subjects (76%) required multiple dose reductions. Eleven subjects (65%) were free of progression at 5 months. The overall response rate was 54% (95% confidence interval [CI], 0.28-077), with 4 patients experiencing complete response (24%; 95% CI, 0.07-0.50) and 5 partial response (29%; 95% CI, 0.10-0.56); 7 subjects (41%) had stable disease. Median PFS was 9.5 months (95% CI, 0.43-1.26), and median overall survival was 25.2 months (95% CI, 0.96-5.65). One-year PFS was 31%, and 1-year overall survival was 72%. Eleven subjects (65%) discontinued treatment because of toxicity. There were no toxic deaths.

CONCLUSION

Gemcitabine and carboplatin with sorafenib showed clinical activity in advanced TCC, with some prolonged progression-free intervals. However, gemcitabine and carboplatin with sorafenib was associated with significant toxicity, causing discontinuation of therapy in most patients.

A phase 1/2 study of a novel IL-2 cytokine, NKTR-214, and nivolumab in patients with select locally advanced or metastatic solid tumors

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Background: NKTR-214 is a CD-122-biased agonist that targets the IL-2 pathway and is designed to provide sustained signaling through the heterodimeric IL-2 receptor pathway (IL-2Rβɣ) to preferentially activate and expand NK and effector CD8+ T cells over T regulatory cells within the tumor microenvironment. In a phase 1 monotherapy trial, pts treated with NKTR-214 demonstrated a substantial increase in CD8+ T and NK cells within the tumor microenvironment even when pretreated with multiple prior immunotherapeutic agents (abstract submitted). Based on this biomarker data and a favorable safety profile, a trial combining NKTR-214 and nivolumab was initiated. Methods: This is an on-going phase 1/2 study of NKTR-214 plus nivolumab in Pts with either melanoma (Mel), NSCLC, renal, bladder, or TNBC. Pts who are immunotherapy naïve or checkpoint therapy relapse/refractory are being studied separately. NKTR-214 and nivolumab are administered IV on a q2w or q3w schedule. Cohort 1 received NKTR-214 0.006 mg/kg q3w with nivolumab 240 mg q2w. Blood and tumor tissue were collected to measure immune activation using flow cytometry, immunohistochemistry, T cell clonality and gene expression analyses. Results: As of February 7, 2017, 5 Pts have been treated with the combination and all Pts were naïve to checkpoint inhibitors. There have been no dose limiting toxicities, no drug-related or immune related grade 3-5 adverse events (TRAEs) and no Pts have discontinued treatment. The most common TRAEs were pruritis and rash. Radiographic scans were available for 2 Pts. On treatment, Pt 1 with Mel had a mixed radiographic response at 1st scan, a ~40% decrease in LDH and a robust tumor immune cell infiltrate at week 3 the majority being newly proliferating CD8+ T cells expressing PD-1. Pt 2 with Mel had an unconfirmed complete response per RECIST 1.1 after 6 weeks of treatment; follow up tumor response data will be presented. Conclusions: Preliminary data demonstrate that NKTR-214 and nivolumab combination therapy is well tolerated with early evidence of clinical activity. Updated safety, pharmacokinetics, tumor response and biomarker data will be presented. Clinical trial information: NCT02983045.

Effect of a novel IL-2 cytokine immune agonist (NKTR-214) on proliferating CD8+T cells and PD-1 expression on immune cells in the tumor microenvironment in patients with prior checkpoint therapy

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Background: NKTR-214 is a CD122-biased agonist designed to provide sustained signaling through the heterodimeric IL-2 receptor pathway (IL-2Rβɣ) to preferentially activate and expand effector CD8+ T and NK cells over T regulatory cells in the tumor microenvironment. Immune changes in the tumor microenvironment after NKTR-214 treatment was assessed in patients with locally advanced or metastatic solid tumors. Methods: NKTR-214 was administered IV in an outpatient setting q2w or q3w. Serial blood and tumor tissue samples were collected to measure immune activation using immunophenotyping including flow cytometry, immunohistochemistry (IHC), T cell clonality and gene expression analyses. Results: 26 patients (pts) have been treated with NKTR-214 at q3w, 4@0.003, 9@0.006, 6@0.009 and 1@0.012 mg/kg. Six pts received 0.006 mg/kg q2w. 58% of pts had prior immunotherapy. The most common Gr1-2 TRAEs were fatigue (73%) and pruritus (65%), and decreased appetite (46%). One pt experienced Gr3 syncope and hypotension at the highest dose tested and continued treatment at a lower dose. No drug-related AEs led to study discontinuation. No immune-related AEs or capillary leak syndrome were observed. 6 pts (23%) experienced tumor shrinkage from 10-30%. Three immunotherapy naïve pts receiving sequential anti-PD1 therapy, after ending treatment with NKTR-214, experienced significant tumor regression at first scan. In all pts evaluated, blood samples showed increases in newly proliferating (Ki67+) T and NK cells 8 days post dose. Flow cytometry and/or IHC revealed an up to 10-fold increase from baseline in tumor CD8+T and NK cells in the tumor microenvironment, with minimal changes to Tregs. PD-1 expression increased 2-fold in TILs. Gene expression analysis of tumor tissue showed increases in several immune checkpoint genes, cytotoxic markers (IFNg, PRF1, and GZMB), as well as a dynamic change in T cell clonality. Conclusions: Based on a favorable safety profile and strong correlative biomarker data, a phase 1/2 trial combining NKTR-214 and nivolumab is currently enrolling. Clinical trial information: NCT02869295.

Effect of NKTR-214 on the number and activity of CD8+ tumor infiltrating lymphocytes in patients with advanced renal cell carcinoma

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Background: Patients with low baseline CD8+ T-cells within the tumor microenvironment (TILs) have a poor response to immune checkpoint inhibitors. Agents designed to specifically activate and expand CD8+ T cells may improve clinical outcomes in patients with low TILs. NKTR-214 is a CD-122-biased agonist designed to provide sustained signaling through the heterodimeric IL-2 receptor pathway (IL-2Rβɣ) and preferentially activate and expand NK and effector CD8+ T cells over CD4+ T regulatory cells. Methods: A dose escalation, open-label, trial was initiated to assess the safety of NKTR-214 and explore immune changes in the blood and tumor microenvironment in patients with advanced solid tumors. NKTR-214 was administered IV in an outpatient setting with initial dosing at 0.003 mg/kg. Pre and post treatment blood and tumor samples were analyzed for immune phenotyping, gene expression, T cell receptor diversity, and changes in the tumor microenvironment by immunohistochemistry. Results: Among 25 patients dosed, 15 had RCC (10@0.006mg/kg, 4@0.009mg/kg, and 1@0.012mg/kg). Treatment with NKTR-214 was well tolerated and the MTD was not reached. One patient experienced DLTs (Gr3 syncope and hypotension) at 0.012 mg/kg. There were no immune-related AEs. Of 12 patients evaluable for response, 75% had SD at their first on treatment scan. Of 5 patients, who were immune checkpoint naïve with ≥ 1 prior TKI treatments, 3 experienced tumor shrinkage, 1 with PR per RECIST 1.1 (unconfirmed). Interrogation of the tumor microenvironment revealed many significant immunological changes post treatment, including increase in total and proliferating NK, CD8+, and CD4+ T cells. There was good correlation between increase in activated CD4+ and CD8+ T cells in peripheral blood with an increase in T cell infiltrates within the tumor tissue. Conclusions: NKTR-214 increased immune infiltration in the tumor and anti-tumor activity in patients who previously progressed on TKIs, with a favorable safety profile. The ability to alter the immune environment and increase PD-1 expression on effectors T cells may improve the effectiveness of anti-PD-1 blockade. A trial combining NKTR-214 and nivolumab is enrolling. Clinical trial information: 02869295.

Changes in T cell immunity in patients with metastatic castration resistant prostate treated with Radium-223 treatment

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Background: The bone seeking calcium mimetic, Radium223 (Ra223), emits high energy alpha particle that cause irreparable double strand DNA breaks in osseous metastases. Ra223 improves survival in patients with bone-predominant metastatic castration resistant prostate cancer (mCRPC). The effect of Ra223 on the host immune system, and T cell immunity in particular, is unknown. Methods: Eligible patients include men with mCRPC, osseous metastases and a clinical indication for Ra223 were eligible. Blood samples were collected at the following time points: prior to the first, second, and fourth treatments (tx) and 4 weeks after the sixth dose. Peripheral blood mononuclear cells (PBMCs) were purified and stained with a cocktail of antibodies to surface and effector immune molecules. Some PBMCs were stimulated and stained for intracellular cytokines (IFN-g, TNF-a, IL-13, IL-17, and IL-21). Stained cells were analyzed by flow cytometry. Results: A total seven patients completed at least two sample collections. The median number of prior lines of therapy was three. Median age was 71 (55-79). Median PSA was 78 (2-351). Effector memory (EM) CD8+ T cells were divided into two subsets expressing high and low levels of the IL-7 receptor alpha chain (IL-7Ra) with distinct cellular characteristics including perforin expression. The frequency of IL-7Rahigh and low EM CD8+ T cells expressing programmed death protein 1 (PD-1) was decreased after Ra223 treatment (pre vs. post, median (%) ± interquartile range, 14.3 ± 12.9 vs. 7.2 ± 20.9, P = 0.03; 16.7 ± 28.8 vs. 14.1 ± 37.8, P = 0.015 by Wilcoxon matched-pairs signed rank test). A similar finding was observed in the frequency of memory CD4+ T cells expressing PD-1 after the treatment (median (%) ± interquartile range, 7.2 ± 7.7 vs. 3.9 ± 3.4, P= 0.03). Conclusions: In this preliminary cohort of patients, Ra223 tx was associated with decrease in PD-1 expression by effector T cells. Further investigations of an immune mechanism of Ra223 mediated antitumor activity are warranted.

The impact of androgen deprivation and pelvic radiation on the development of bladder cancer

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Background: The male predilection of urothelial bladder cancer (UBC) as well as the expression of the androgen receptor in bladder tissue point to the role for androgens in UBC tumorigenesis. Animal studies demonstrate a potential role for androgen deprivation in diminishing UBC. More recently, two separate groups demonstrated decreased rates of both primary and recurrent UBC in prostate cancer patients previously receiving androgen deprivation therapy (ADT). Given the common use of radiation therapy (RT) in the treatment of localized prostate cancer, and previous data supporting the increased frequency of UBC in prostate cancer patients treated with RT, the interaction between ADT and RT in UBC remains an important consideration. Methods: Using the linked SEER-Medicare database, we investigated the interactions among ADT, RT and UBC by performing a retrospective cohort study of elderly (age 66-99) prostate cancer patients diagnosed between 1999-2011. Kaplan-Meier analysis and Cox proportional modeling were used to determine the risk of developing secondary bladder cancer after prostate cancer treatment (based on exposure to ADT, RT, both, or neither). All analyses were two-sided. Results: Of 121,927 patients with primary prostate cancer, 1,466 (1.20%) developed subsequent UBC with a median follow up of 5.08 years (range 0.003-12.00). Compared with patients never receiving ADT or RT (n = 43,809), the hazard ratios for the development of secondary bladder cancer in patients ever receiving ADT but no RT (n = 14,009), RT but no ADT (n = 16,672), or both ADT and RT (n = 17,465) were 0.76 (95% confidence interval [CI]: 0.63-0.91 ), 0.73 (95% CI: 0.64-0.83), and 0.69 (95% CI: 0.61-0.79), respectively. Conclusions: Both ADT and RT are independently associated with a reduced risk of secondary bladder cancers in prostate cancer patients. The finding of decreased UBC incidence in patients receiving RT was surprising, and in direct contradiction to previous studies of similar patient populations. Possible explanations include differences in cohort selection, changes in RT delivery, and differences in control groups.

Abl kinase inhibits the engulfment of apoptotic [corrected] cells in Caenorhabditis elegans

The engulfment of apoptotic cells is required for normal metazoan development and tissue remodeling. In Caenorhabditis elegans, two parallel and partially redundant conserved pathways act in cell-corpse engulfment. One pathway includes the adaptor protein CED-2 CrkII and the small GTPase CED-10 Rac, and acts to rearrange the cytoskeleton of the engulfing cell. The other pathway includes the receptor tyrosine kinase CED-1 and might recruit membranes to extend the surface of the engulfing cell. Although many components required for engulfment have been identified, little is known about inhibition of engulfment. The tyrosine kinase Abl regulates the actin cytoskeleton in mammals and Drosophila in multiple ways. For example, Abl inhibits cell migration via phosphorylation of CrkII. We tested whether ABL-1, the C. elegans ortholog of Abl, inhibits the CED-2 CrkII-dependent engulfment of apoptotic cells. Our genetic studies indicate that ABL-1 inhibits apoptotic cell engulfment, but not through CED-2 CrkII, and instead acts in parallel to the two known engulfment pathways. The CED-10 Rac pathway is also required for proper migration of the distal tip cells (DTCs) during the development of the C. elegans gonad. The loss of ABL-1 function partially restores normal DTC migration in the CED-10 Rac pathway mutants. We found that ABI-1 the C. elegans homolog of mammalian Abi (Abl interactor) proteins, is required for engulfment of apoptotic cells and proper DTC migration. Like Abl, Abi proteins are cytoskeletal regulators. ABI-1 acts in parallel to the two known engulfment pathways, likely downstream of ABL-1. ABL-1 and ABI-1 interact physically in vitro. We propose that ABL-1 opposes the engulfment of apoptotic cells by inhibiting ABI-1 via a pathway that is distinct from the two known engulfment pathways.

Cell death or apoptosis is a normal part of animal development, as is the engulfment and removal of dead cells by other cells. In the nematode Caenorhabditis elegans, ten highly conserved proteins have been characterized previously for their roles in engulfment and in cell migration, both of which involve the formation of cellular extensions. Little is known, however, about how engulfment is inhibited. In mammals, the tyrosine kinase Abl, which regulates the actin cytoskeleton and which when misexpressed causes two types of leukemia, prevents the CrkII protein from facilitating cell migration. CrkII functions in engulfment in C. elegans and mammals. We tested whether the C. elegans homolog of Abl, ABL-1, could inhibit engulfment. We found that ABL-1 functions as an inhibitor of apoptotic cell engulfment and cell migration. However, our analysis further showed that ABL-1 does not function by inhibiting other known engulfment proteins, including C. elegans CrkII. Our data indicate that ABL-1 blocks ABI-1, the C. elegans homolog of the mammalian and Drosophila Abl-interactor (Abi) cytoskeletal-regulatory proteins. We propose that ABL-1 acts via ABI-1 to inhibit a newly identified pathway during cell corpse engulfment and cell migration.

We show thatC. elegans Abl (ABL-1) inhibits the engulfment of apoptotic cells via a newly defined pathway that includes theC. elegans homolog of the cytoskeletal regulator Abl-interactor.

C. elegans CARMIL negatively regulates UNC-73/Trio function during neuronal development

Whereas many molecules that promote cell and axonal growth cone migrations have been identified, few are known to inhibit these processes. In genetic screens designed to identify molecules that negatively regulate such migrations, we identified CRML-1, the C. elegans homolog of CARMIL. Although mammalian CARMIL acts to promote the migration of glioblastoma cells, we found that CRML-1 acts as a negative regulator of neuronal cell and axon growth cone migrations. Genetic evidence indicates that CRML-1 regulates these migrations by inhibiting the Rac GEF activity of UNC-73, a homolog of the Rac and Rho GEF Trio. The antagonistic effects of CRML-1 and UNC-73 can control the direction of growth cone migration by regulating the levels of the SAX-3 (a Robo homolog) guidance receptor. Consistent with the hypothesis that CRML-1 negatively regulates UNC-73 activity, these two proteins form a complex in vivo. Based on these observations, we propose a role for CRML-1 as a novel regulator of cell and axon migrations that acts through inhibition of Rac signaling.

Use of computerized tomography and chest x-rays in evaluating efficacy of aerosolized recombinant human DNase in cystic fibrosis patients younger than age 5 years: a preliminary study

The aim of this study was to evaluate the ability of high-resolution computerized tomography (HRCT) of the chest and chest x-rays (CXR) to determine efficacy of inhaled recombinant human DNase (rhDNase) in cystic fibrosis (CF) patients younger than 5 years of age. A randomized, double-blind, placebo-controlled pilot study of 12 patients with CF younger than 5 years of age, attending the University of Michigan Cystic Fibrosis Center (Ann Arbor, MI) was conducted. The changes in the HRCT and CXR score from baseline to day 100 of therapy were assessed using a previously validated scoring system. The mean changes of HRCT scores between the rhDNase and placebo groups were found to be significant at the 95% level, with mean change +/- SE mean of - 1.00 +/- 0.53 and 0.58 +/- 0.24 for rhDNase and placebo groups, respectively (P = 0.02). The difference in CXR score was not significant between the two groups. An analysis was performed to relate HRCT subscores to CXR score; only thickening of the intra-interlobular septae was significantly correlated with the total CXR score (r = - 0.7, P < 0.01). There was improvement in the parents' assessments of the patients' well-being, with improvement in physical activity, decreased cough, sleep quality, and appetite in those subjects receiving rhDNase. We conclude that the administration of rhDNase was associated with improvement in the HRCT scan in CF patients younger than 5 years of age. Findings indicate that HRCT of the chest is useful and sensitive in studying responses to therapy in patients with CF lung disease. To our knowledge, this is the first report of the use of HRCT to assess the effectiveness of a therapeutic modality in so young a CF patient population.

Treatment of anorexia and weight loss with megestrol acetate in patients with cystic fibrosis

Four patients with severe cystic fibrosis lung disease, anorexia and weight loss, received Megestrol Acetate (MA), as an appetite stimulant. The initial dose was 400-800 mg daily and was continued for 6-15 months. Appetite was improved, with significant weight gain in all patients and an increase in their weight for age percentile from <5% at the start of the study to approximately the 25(th) percentile after 6 months of use and improvement in quality of life. One patient discontinued MA after 6 months, and subsequently appetite and weight were depressed.

Two yeast nuclear pore complex proteins involved in mRNA export form a cytoplasmically oriented subcomplex

We sublocalized the yeast nucleoporin Nup82 to the cytoplasmic side of the nuclear pore complex (NPC) by immunoelectron microscopy. Moreover, by in vitro binding assays we showed that Nup82 interacts with the C-terminal region of Nup159, a yeast nucleoporin that previously was also localized to the cytoplasmic side of the NPC. Hence, the two nucleoporins, Nup82 and Nup159, form a cytoplasmically oriented subcomplex that is likely to be part of the fibers emanating from the cytoplasmic ring of the NPC. Overexpression of Rss1/Gle1, a putative nucleoporin and/or mRNA transport factor, was shown previously to partially rescue depletion of Nup159. We show here that overexpression of Rss1/Gle1 also partially rescued depletion of Nup82. Depletion of either Nup82, Nup159, or Rss1/Gle1 was shown previously to inhibit mRNA export. As was reported previously for depletion of Nup159 or of Rss1/Gle1, we show here that depletion of Nup82 has no detectable effect on classical nuclear localization sequence-mediated nuclear import. In summary, the nucleoporins Nup159 and Nup82 form a cytoplasmically oriented subcomplex of the NPC that is likely associated with Rss1/Gle1; this complex is essential for RNA export, but not for classical nuclear localization sequence-mediated nuclear protein import.

A scale for Assessing Health Care Providers' Teaching and Communication Behavior regarding asthma

Partnership between health care providers and patients is important for controlling illness. A limited number of studies show how to assess health professionals' communication and partnering behavior. The relationship between these aspects of professional behavior and enhanced management of disease by patients has received little empirical study. The research reported here developed a Health Care Providers' Teaching and Communication Behavior (TCB) scale for assessing the teaching and communication behavior of clinicians treating patients with asthma. Such a tool is needed for research related to provider-patient relationships and for evaluation of professionals' performance.

NUP82 is an essential yeast nucleoporin required for poly(A)+ RNA export

We have isolated and characterized the gene encoding a novel essential nucleoporin of 82 kD, termed NUP82. Indirect immunofluorescence of cells containing an epitope tagged copy of the NUP82 localized it to the nuclear pore complex (NPC). Primary structure analysis indicates that the COOH-terminal 195 amino acids contain a putative coiled-coil domain. Deletion of the COOH-terminal 87 amino acids of this domain causes slower cell growth; deletion of the COOH-terminal 108 amino acids results in slower growth at 30 degrees C and lethality at 37 degrees C. Cells in which the last 108 amino acids of NUP82 have been deleted, when shifted to 37 degrees C, do not display any gross morphological defects in their nuclear pore complexes or nuclear envelopes. They do, however, accumulate poly(A)+ RNA in their nuclei at 37 degrees C. We propose that NUP82 acts as a linker to tether nucleoporins directly involved in nuclear transport to pore scaffolding via its coiled-coil domain.

Improvement in clinical asthma score and PaCO2 in children with severe asthma treated with continuously nebulized terbutaline

We analyzed continuous nebulized terbutaline (CNT) therapy in 19 patients with 27 admissions for severe asthma and impending respiratory failure who failed to respond to our standard asthma protocol of methylprednisolone, aminophylline, and intermittently nebulized terbutaline. Terbutaline was administered by continuous face mask nebulization at a dose equaling the most frequent previous intermittent dose per hour (4 mg per hour). No patient with frank respiratory failure (i.e., PaCO2 greater than or equal to 60 torr, exhaustion, or coma) was studied. All patients improved, and therapy was stopped in a mean of 15.4 hours (range 3 to 37 hours). The average heart rate did not increase over baseline measurements through 24 hours of CNT. The mean clinical asthma score improved significantly during 8 hours, falling from 6.9 to 3.2 (p greater than 0.001). In 14 patients whose PaCO2 was greater than or equal to 39 torr (range 39 to 58 torr) and clinical asthma score was 6 or greater, PaCO2 decreased a mean of 11.7 torr during a mean of 8.1 hours. In six patients whose PaCO2 was 45 torr or greater at the start of CNT (mean 49, range 45 to 58 torr) and in whom we would have previously treated with intravenous isoproterenol, PaCO2 decreased a mean of 15 torr in an average of 8.7 hours. This preliminary study suggests that CNT is an effective therapy for severe asthma in children.

Clinical scoring does not accurately assess hypoxemia in pediatric asthma patients

Management of acute asthma in the pediatric population is based almost entirely on clinical evidence of severity. Although pulmonary function testing has been advocated to improve evaluation, it is difficult in the pediatric patient and not routinely practiced. A clinical scoring system has been devised to help standardize evaluation, but has not been validated by comparison of the results of clinical scoring with those of arterial blood oxygen levels as determined by blood gas analysis. This study was undertaken to compare clinical scoring of pediatric asthma patients with the results of arterial blood gas analysis. Thirty-eight children between the ages of 2 and 13 having 42 episodes of acute asthma were evaluated. The average age was 5.4 years. The average clinical score was 2.62; arterial blood for analysis was obtained in 37 (88%), with an average PaO2 of 81.7 mm Hg. None of the children had CO2 retention. There was no correlation between the clinical score of the children on presentation and the severity of hypoxia (correlation coefficient = -0.149). Comparison of age and arterial oxygen tension revealed a trend toward worsening hypoxemia with diminishing age from 6 to 2 years, which was not identified by clinical scoring. We conclude that clinical scoring is inaccurate for the assessment of hypoxemia in the pediatric age group. Arterial blood gas determination should be used to assess the severity of hypoxemia in the emergency treatment of pediatric asthma patients.