Neoadjuvant Chemotherapy with Accelerated Methotrexate, Vinblastine, Doxorubicin, and Cisplatin in Patients with Muscle-invasive Bladder Cancer: A Retrospective Age-stratified Analysis on Safety and Efficacy

BACKGROUND

The standard of care (SOC) for muscle-invasive bladder cancer (MIBC) includes cisplatin-based combination chemotherapy in the neoadjuvant setting followed by radical cystectomy. Older patients often do not receive SOC due to perceived toxicity concerns despite guideline-directed recommendations.

OBJECTIVE

To characterize the safety and efficacy of neoadjuvant accelerated methotrexate, vinblastine, adriamycin, and cisplatin (aMVAC) in MIBC patients as a function of age.

DESIGN, SETTING, AND PARTICIPANTS

A retrospective analysis was conducted in 186 MIBC patients treated at Fox Chase Cancer Center between January 1, 2002 and December 31, 2018. Adults with histologically proven muscle-invasive urothelial cancer were eligible. The exclusion criteria included nonurothelial histology, lack of muscularis propria invasion, and primary upper tract or metastatic disease.

INTERVENTION

Neoadjuvant chemotherapy with aMVAC.

OUTCOME MEASUREMENTS AND STATISTICAL ANALYSIS

Patients were stratified by age (<65, 65-74, and >75 yr old). Renal function was assessed at baseline and at time points after treatment. Clinicopathologic variables were compared between age groups to determine efficacy.

RESULTS AND LIMITATIONS

There were no statistically significant differences in dose reductions, treatment interruptions, time to surgery, or adverse events when patients were stratified by age in univariate and multivariate analyses. Full safety data were not available due to the retrospective nature of the study. Baseline renal function was significantly worse among older patients, and the percent decline in creatinine clearance was greater with older age. We found comparable efficacy of aMVAC regardless of age.

CONCLUSIONS

Accelerated MVAC was safe and demonstrated efficacy in MIBC irrespective of age in this single-center, retrospective study. Careful selection based on clinical variables, and not age, should identify patients able to receive neoadjuvant chemotherapy.

PATIENT SUMMARY

We examined the feasibility of the standard cisplatin-based chemotherapy regimen given prior to surgery in patients with muscle-invasive bladder cancer. Elderly patients experienced a greater decline in kidney function with treatment but not more complications than younger patients and tolerated therapy with minimal dose changes, resulting in benefit regardless of age.

A phase 1 study of nivolumab in combination with interferon-gamma for patients with advanced solid tumors

This phase I, dose-escalation trial evaluates the safety of combining interferon-gamma (IFN-γ) and nivolumab in patients with metastatic solid tumors. Twenty-six patients are treated in four cohorts assessing increasing doses of IFN-γ with nivolumab to evaluate the primary endpoint of safety and determine the recommended phase two dose (RP2D). Most common adverse events are low grade and associated with IFN-γ. Three dose limiting toxicities are reported at the highest dose cohorts. We report only one patient with any immune related adverse event (irAE). No irAEs ≥ grade 3 are observed and no patients require corticosteroids. The maximum tolerated dose of IFN-γ is 75 mcg/m², however based on a composite of safety, clinical, and correlative factors the RP2D is 50 mcg/m². Exploratory analyses of efficacy in the phase I cohorts demonstrate one patient with a complete response, and five have achieved stable disease. Pre-planned correlative assessments of circulating immune cells demonstrate intermediate monocytes with increased PD-L1 expression correlating with IFN-γ dose and treatment duration. Interestingly, post-hoc analysis shows that IFN-γ induction increases circulating chemokines and is associated with an observed paucity of irAEs, warranting further evaluation. ClinicalTrials.gov Trial Registration: NCT02614456.

A Phase II Trial of Guadecitabine plus Atezolizumab in Metastatic Urothelial Carcinoma Progressing after Initial Immune Checkpoint Inhibitor Therapy

PURPOSE

Based on preclinical evidence of epigenetic contribution to sensitivity and resistance to immune checkpoint inhibitors (ICI), we hypothesized that guadecitabine (hypomethylating agent) and atezolizumab (anti-PD-L1) together would potentiate a clinical response in patients with metastatic urothelial carcinoma (UC) unresponsive to initial immune checkpoint blockade therapy.

PATIENTS AND METHODS

We designed a single arm Phase II study (NCT03179943) with a safety run-in to identify the recommended phase II dose of the combination therapy of guadecitabine and atezolizumab. Patients with recurrent/advanced urothelial carcinoma who had previously progressed on ICI therapy with PD-1 or PD-L1 targeting agents were eligible. Pre-planned correlative analysis was performed to characterize peripheral immune dynamics and global DNA methylation, transcriptome, and immune infiltration dynamics of patient tumors.

RESULTS

Safety run-in enrolled 6 patients and Phase II enrolled 15 patients before the trial was closed for futility. No dose-limiting toxicity was observed. Four patients, with best response of stable disease, exhibited extended tumor control (8-11 months) and survival (>14 months). Correlative analysis revealed lack of DNA demethylation in tumors after 2 cycles of treatment. Increased peripheral immune activation and immune infiltration in tumors after treatment correlated with progression-free survival and stable disease. Furthermore, high IL-6 and IL-8 levels in the patients' plasma associates with short survival.

CONCLUSIONS

No RECIST responses were observed after combination therapy in this trial. Although we could not detect the anticipated tumor-intrinsic effects of guadecitabine, the addition of hypomethylating agent to ICI therapy induced immune activation in a few patients, which associated with longer patient survival.

S1314 correlative analysis of ATM, RB1, ERCC2, and FANCC mutations and pathologic complete response (pT0) at cystectomy after neoadjuvant chemotherapy (NAC) in patients with muscle invasive bladder cancer (MIBC): Implications for bladder preservation

4581

Background: SWOG S1314 (NCT02177695) was designed to validate the CoXEN classifier as a predictive biomarker in pts undergoing cystectomy after NAC. We repurposed banked DNA samples and prospective trial data from S1314 to further validate the predictive ability of the Philadelphia 4 gene signature (P4GS: any mutation in ATM, RB1, FANCC, ERCC2) to predict pT0 as previously reported (PMID: 26238431) and used in the RETAIN trial (NCT02710734). The RETAIN trial prospectively enrolled pts to receive NAC (DDMVAC) followed by allocation to bladder observation vs. intervention (cystectomy or RT) based on clinical evaluation and presence vs absence of P4GS. The primary objective of this correlative investigation was to determine whether presence of P4GS is predictive of pT0 at surgery. Methods: Eligibility for S1314 included cT2-T4a N0 M0 MIBC, cisplatin eligible, with plan for cystectomy; 237 pts were randomized between ddMVAC and gem/cis (GC) using standard dose/schedule. Of 167 pts who were evaluable for the original COXEN analysis (received 3+ cycles of chemo and evaluable for path response) adequate banked DNA was available for 105. Next-generation sequencing using the CARIS 592 Gene Panel (Caris Life Sciences, Phoenix, AZ) was performed. Pathogenic mutation or VUS of ATM, RB1, FANCC or ERCC2 was noted as present or absent for each pt and correlated with pT0 using logistic regression, adjusting for clinical stage. Results: Among the 105 pts, 51% ddMVAC, 49% GC. 15% female, 95% white, 15% clinical stage T3/T4a Prevalence of mutations: ATM (24%), ERCC2 (17%), FANCC (4%), RB1 (24%) and any variant 53%. Presence of any mutation correlated with pT0 (p = 0.0006), sensitivity 79%, specificity 59%. This association did not vary by treatment arm (MVAC vs. GC). The table below shows the contributions of each of the 4 genes with the greatest contribution from ATM and ERCC2. FANCC was non-contributory due to low prevalence. Conclusions: Patients with a mutation in ATM, RB1, FANCC or ERCC2 (P4GS) have a statistically significantly higher odds of a pT0 with GC or MVAC compared to those who do not have any variant. This signature was used to prospectively allocate patients to bladder observation as part of the RETAIN trial previously reported (ASCO GU 2021). RETAIN completed enrollment, final analysis of the primary endpoint – 2-year metastasis free survival – is expected later in 2022. Clinical trial information: NCT02177695.

A phase I/II study of nivolumab and axitinib in patients with advanced renal cell carcinoma

291

Background: Combination systemic therapy with tyrosine kinase inhibitors (TKIs) and an immune checkpoint inhibitor (IO) are an established standard of care for patients with metastatic renal cell carcinoma (mRCC). We performed a phase I/II study to investigate the safety and efficacy combining the TKI axitinib (axi) with the IO agent nivolumab (nivo). Methods: This phase I/II study investigated the combination of axi and nivo in an initial dose finding phase I portion with a 3+3 design to determine the recommended phase 2 dose (RP2D) of axi. The phase II portion included 2 parallel arms: treatment naïve mRCC patients and mRCC patients previously treated with TKIs alone or IO/IO combination (NCT03172754). We are presenting results from the treatment naïve arm only. Included patients had to have histology with any clear cell component, ECOG performance status of 0-1, no known or symptomatic brain metastases, and no history of autoimmune disease. The RP2D of axi was 5 mg BID from the phase I portion and patients could be treated for up to 2 years. The primary endpoint of the phase II portion was objective response rate (ORR) per investigator assessment. Results: Forty-four patients were accrued to the treatment naïve arm. One withdrew consent and was replaced but is included in the safety analysis, while 42 patients are evaluable for efficacy. The median age was 65 yrs (range: 42-84 yrs) and the group was predominantly male (83.7%) and white (95.3%). Using the IMDC risk group grading, 18 patients (41.9%) were favorable risk, 22 patients (51.2%) were intermediate risk and 3 patients (7 %) were poor risk. Median follow-up was 11.5 months. Best response data is shown in the table and is notable for an ORR of 69.0%, with only 1 patient (2.4%) experiencing primary progressive disease, for a disease control rate of 97.6%. Median progression free survival was 16.4 months (95% CI: 10.6 - 21.9 mo), and median overall survival (OS) was not reached. OS at 12 months was 86.7%. Adverse event (AE) data was similar to published data for IO/TKI combinations, with no grade 4-5 AEs. Twenty-nine patients experienced a grade 3 AE (70.7%), the most common of which was hypertension, and 14.0% discontinued the study due to treatment-related toxicity. Conclusions: The combination of axi/nivo for treatment naïve patients with mRCC demonstrated efficacy comparable to available IO/TKI combinations with a similar safety profile. Clinical trial information: NCT03172754. [Table: see text]

D-cycloserine nasal formulation development for anxiety disorders by using polymeric gels

D-cycloserine (DCS), a partial agonist at N-methyl-D-aspartate (NMDA) receptors, is used as an enhancer of exposure therapy for anxiety disorders. The purpose of the present study was to investigate the feasibility of using polymeric gels to increase the viscosity of the formulation and thereby increase the nasal residence time and sustained release of DCS in vitro. Hydroxypropyl methylcellulose (HPMC), hydroxypropyl cellulose (HPC), and methyl cellulose (MC) were prepared at concentrations of 0.5 to 5% w/v. Pluronic F-127 (PF-127) was prepared at concentrations of 15 to 35% w/v. pH, viscosity and in vitro DCS release behavior of the formulated gels were analyzed. All four gels that were tested, demonstrated sustained DCS release behavior over a 24-hour period, but with different rates. Based on the results of this study, HPMC, HPC, MC, and PF-127 are capable of increasing the viscosity of nasal gel formulations and of releasing DCS in sustained manner. Therefore, these polymeric gels can be suitable carriers for DCS nasal gel formulation.

Abstract LB-049: Differential effects of functionalized and non-functionalized short multi-wall carbon nanotubes on survival of pancreatic cancer cells

Pancreatic cancer is an aggressive type of cancer with poor prognosis and low five-year survival rate. Current treatments such as chemotherapy and radiation therapy are not effective. Thus, new therapeutic strategies are urgently needed to treat patients with this devastating disease and to improve their prognosis. Carbon nanotubes (CNTs) constitute a novel nanomaterial extensively studied to develop and exploit their potential in biomedical applications (e.g. drug delivery vehicles and diagnostic agents), including cancer nanobiomedicine. Modification of CNTs with functional groups may improve their aqueous solubility and selectively facilitate the attachment of drugs as well as macromolecules to CNTs, thereby creating new avenues for designing novel and highly targeted drugs. Even though the putative cytotoxicity of functionalized and non-functionalized CNTs is poorly understood, it can be gainfully exploited to enhance the efficacy of anti-cancer drugs. The aim is this study is to investigate the hypothesis that functionalized and non-functionalized CNTs exert differential cytotoxic effects on pancreatic cancer cells. We employed the MTT assay to determine the effects of functionalized and non-functionalized short multi-wall carbon nanotubes (SMWCNTs) on survival of PANC1 cells and Western-blot analysis to elucidate some of the cell survival/proliferation mechanisms (e.g., ERG) underlying the effects induced by SMWCNTs. We used the Seahorse XFp technology to examine the effects of the SMWCNTs on cellular energetics (especially glycolysis & mitochondrial metabolism) in pancreatic cancer cells. Additionally, we employed Annexin V/PI staining in combination with flow cytometry to determine the effects of SMWCNTs in inducing apoptosis in MiaPaca-2 cells. Dose-response studies on pancreatic cancer cells using the MTT assay indicated non-functionalized CNTs to be more cytotoxic than functionalized CNTs. Cell signaling studies indicate no alteration in AKT & phospho-AKT levels between functionalized & non-functionalized CNTs treatment. However, phospho-ERK levels were observed to consistently decrease with increasing concentrations of non-functionalized CNTs. Flow cytometric analysis showed increased apoptotic cell death with non-functionalized CNTs relative to that with functionalized CNTs. Overall, results from these studies indicate the differential effects of CNTs (functionalized versus non-functionalized) on pancreatic cancer cells and as such they may have implications in designing novel therapies for treatment of pancreatic cancer.

Citation Format: Alok Bhushan, Rutika Kokate, Vilas Desai, Annie Chhun, Gagan Kaushal, Yao Zhang, James Lai. Differential effects of functionalized and non-functionalized short multi-wall carbon nanotubes on survival of pancreatic cancer cells. [abstract]. In: Proceedings of the 107th Annual Meeting of the American Association for Cancer Research; 2016 Apr 16-20; New Orleans, LA. Philadelphia (PA): AACR; Cancer Res 2016;76(14 Suppl):Abstract nr LB-049.

Resonance energy transfer between fluorescent BSA protected Au nanoclusters and organic fluorophores

Bovine serum albumin (BSA) protected nanoclusters (Au and Ag) represent a group of nanomaterials that holds great promise in biophysical applications due to their unique fluorescence properties and lack of toxicity. These metal nanoclusters have utility in a variety of disciplines including catalysis, biosensing, photonics, imaging and molecular electronics. However, they suffer from several disadvantages such as low fluorescence quantum efficiency (typically near 6%) and broad emission spectrum (540 nm to 800 nm). We describe an approach to enhance the apparent brightness of BSA Au clusters by linking them with a high extinction donor organic dye pacific blue (PB). In this conjugate PB acts as a donor to BSA Au clusters and enhances its brightness by resonance energy transfer (RET). We found that the emission of BSA Au clusters can be enhanced by a magnitude of two-fold by resonance energy transfer (RET) from the high extinction donor PB, and BSA Au clusters can act as an acceptor to nanosecond lifetime organic dyes. By pumping the BSA Au clusters using a high extinction donor, one can increase the effective brightness of less bright fluorophores like BSA Au clusters. Moreover, we prepared another conjugate of BSA Au clusters with the near infrared (NIR) dye Dylight 750 (Dy750), where BSA Au clusters act as a donor to Dy750. We observed that BSA Au clusters can function as a donor, showing 46% transfer efficiency to the NIR dye Dy750 with a long lifetime component in the acceptor decay through RET. Such RET-based probes can be used to prevent the problems of a broad emission spectrum associated with the BSA Au clusters. Moreover, transferring energy from BSA Au clusters to Dy750 will result in a RET probe with a narrow emission spectrum and long lifetime component which can be utilized in imaging applications.

Long-lived bright red emitting azaoxa-triangulenium fluorophores

The fluorescence lifetimes of most red emitting organic probes are under 4 nanoseconds, which is a limiting factor in studying interactions and conformational dynamics of macromolecules. In addition, the nanosecond background autofluorescence is a significant interference during fluorescence measurements in cellular environment. Therefore, red fluorophores with longer lifetimes will be immensely helpful. Azaoxa-triangulenium fluorophores ADOTA and DAOTA are red emitting small organic molecules with high quantum yield, long fluorescence lifetime and high limiting anisotropy. In aqueous environment, ADOTA and DAOTA absorption and emission maxima are respectively 540 nm and 556 nm, and 556 nm and 589 nm. Their emission extends beyond 700 nm. Both probes have the limiting anisotropy between 0.36-0.38 at their absorption peak. In both protic and aprotic solvents, their lifetimes are around 20 ns, making them among the longest-lived red emitting organic fluorophores. Upon labeling of avidin, streptavidin and immunoglobulin their absorption and fluorescence are red-shifted. Unlike in free form, the protein-conjugated probes have heterogeneous fluorescence decays, with the presence of both significantly quenched and unquenched populations. Despite the presence of significant local motions due to a flexible trimethylene linker, we successfully measured both intermediate nanosecond intra-protein motions and slower rotational correlation times approaching 100 ns. Their long lifetimes are unaffected by the cell membrane (hexadecyl-ADOTA) and the intra-cellular (DAOTA-Arginine) localization. Their long lifetimes also enabled successful time-gating of the cellular autofluorescence resulting in background-free fluorescence lifetime based images. ADOTA and DAOTA retain a long fluorescence lifetime when free, as protein conjugate, in membranes and inside the cell. Our successful measurements of intermediate nanosecond internal motions and long correlations times of large proteins suggest that these probes will be highly useful to study slower intra-molecular motions and interactions among macromolecules. The fluorescence lifetime facilitated gating of cellular nanosecond autofluorescence should be of considerable help in in vitro and in vivo applications.

Abstract 1270: Mimicking infection for immunotherapy against breast cancer - fooling the immune system

Short description: Immunotherapy represents a potential and innovative means to combat cancer. It essentially harnesses the body's immune system to fight against cancer. Previous literature suggests that cancer vaccines designed against a specific tumor antigen have been efficiently utilized to trigger immune responses against tumor cells. Despite the preliminary evidence in animal models, low immunogenicity is one of the major hurdles in the development of vaccines in humans. In order to surmount this obstacle, several approaches including the use of an “ideal” tumor antigen, appropriate delivery techniques, immune boosting strategies with co-stimulatory molecules are being explored.

Purpose: The purpose of this study was to develop “bacteriomimetic nanoparticles” to enhance adaptive cell-mediated immune responses (CD4+ and CD8+ T cell responses) against tumor antigen as a therapeutic option for cancer treatment.

Materials and Methods: NPs were prepared by modified solid/oil/water solvent evaporation method using an ultrasonic processor UP200H system (Hielscher Ultrasonics GmbH, Germany). We used membrane preparations of the 4T1 mouse mammary cancer cell line as a tumor antigen and CpG ODN's as a “bactriomimetic” stimulant. Fourteen days before tumor challenge BALB/c female mice (6-8 weeks) were pre-immunized with CpG followed by secondary immunization using respective NPs encapsulated with the membrane antigen preparation. Subsequently, mice (n=4) were challenged with 105 tumor cells intravenously (IV). Mice were sacrificed and tumors were harvested at days 3, 7 and 14 respectively. CD4+ and CD8+ T cell responses were measured in lower respiratory node and spleen using flow cytometry. In another experimental set, following the same immunization schedule as mentioned above, mice (n=5) were challenged subcutaneously (SC) with 105 tumor cells. Primary tumor size was monitored using vernier caliper and bioluminiscence imaging (Caliper Life Sciences Inc., MA, USA). Mice were sacrificed on day sixteen after tumor challenge; spleen cells were used for flow cytometric analysis and primary tumor tissue was used to evaluate CD4+ and CD8+ T cell via immunohistochemistry.

Results: We found significant reduction in progression of tumor growth in mice immunized with CpG coated NPs containing tumor antigen (CpG-NP-Tag). Cytometry analysis demonstrated increased CD4+ (helper) and CD8+ (cytotoxic) T cell response emphasizing enhanced immunogenicity against cancer cells. IHC data indicated greater CD4+ T cell infiltration of the tumor tissue for the animals immunized with CpG-NP-Tag.

Conclusions: Primary tumor size, IHC and flow cytometry analysis indicate that CpG-NP-Tag NPs were successfully employed to boost the immune response against tumor cells.

Citation Format: Rutika Kokate, Sanjay Thamake, Harlan Jones, Jamboor Vishwanatha, Brittany Mott. Mimicking infection for immunotherapy against breast cancer - fooling the immune system. [abstract]. In: Proceedings of the 104th Annual Meeting of the American Association for Cancer Research; 2013 Apr 6-10; Washington, DC. Philadelphia (PA): AACR; Cancer Res 2013;73(8 Suppl):Abstract nr 1270. doi:10.1158/1538-7445.AM2013-1270