Therapeutic Implications of Tumor Microenvironment in Lung Cancer: Focus on Immune Checkpoint Blockade

In the last decade, the treatment of non-small cell lung cancer (NSCLC) has been revolutionized by the introduction of immune checkpoint inhibitors (ICI) directed against programmed death protein 1 (PD-1) and its ligand (PD-L1), or cytotoxic T lymphocyte antigen 4 (CTLA-4). In spite of these improvements, some patients do not achieve any benefit from ICI, and inevitably develop resistance to therapy over time. Tumor microenvironment (TME) might influence response to immunotherapy due to its prominent role in the multiple interactions between neoplastic cells and the immune system. Studies investigating lung cancer from the perspective of TME pointed out a complex scenario where tumor angiogenesis, soluble factors, immune suppressive/regulatory elements and cells composing TME itself participate to tumor growth. In this review, we point out the current state of knowledge involving the relationship between tumor cells and the components of TME in NSCLC as well as their interactions with immunotherapy providing an update on novel predictors of benefit from currently employed ICI or new therapeutic targets of investigational agents. In first place, increasing evidence suggests that TME might represent a promising biomarker of sensitivity to ICI, based on the presence of immune-modulating cells, such as Treg, myeloid derived suppressor cells, and tumor associated macrophages, which are known to induce an immunosuppressive environment, poorly responsive to ICI. Consequently, multiple clinical studies have been designed to influence TME towards a pro-immunogenic state and subsequently improve the activity of ICI. Currently, the mostly employed approach relies on the association of “classic” ICI targeting PD-1/PD-L1 and novel agents directed on molecules, such as LAG-3 and TIM-3. To date, some trials have already shown promising results, while a multitude of prospective studies are ongoing, and their results might significantly influence the future approach to cancer immunotherapy.

Blast and accelerated phase CML: room for improvement

Tyrosine kinase inhibitors (TKIs) revolutionized the treatment of chronic myeloid leukemia (CML). With TKI therapy, the percentage of patients who progress to accelerated phase (AP) or blast phase (BP) CML has decreased from more than 20% to 1% to 1.5% per year. Although AP- and BP-CML occur in a minority of patients, outcomes in these patients are significantly worse compared with chronic phase CML, with decreased response rates and duration of response to TKI. Despite this, TKIs have improved outcomes in advanced phase CML, particularly in de novo AP patients, but are often inadequate for lasting remissions. The goal of initial therapy in advanced CML is a return to a chronic phase followed by consideration for bone marrow transplantation. The addition of induction chemotherapy with TKI is often necessary for achievement of a second chronic phase. Given the small population of patients with advanced CML, development of novel treatment strategies and investigational agents is challenging, although clinical trial participation is encouraged in AP and BP patients, whenever possible. We review the overall management approach to advanced CML, including TKI selection, combination therapy, consideration of transplant, and novel agents.

Treatment-induced sarcoidosis in a patient with metastatic clear cell ovarian cancer

Sarcoidosis is a granulomatous disease that commonly presents with lung or lymphatic system manifestations. Diagnosis is often delayed due to variable clinical presentation. This is a case of a patient with metastatic clear cell ovarian cancer who developed disease reoccurence after definitive treatment with surgery and adjuvant chemotherapy. She was treated with multiple lines of therapy, including investigational agents. During this time, she developed mediastinal lymphadenopathy and hypercalcaemia. Due to suspicion that her presentation was not a manifestation of her malignancy, she underwent two lymph node biopsies revealing granulomatous disease. She was initiated on prednisone for management of sarcoidosis, which led to radiologic, laboratory and symptomatic improvement. Although the precipitating factor for this patient’s sarcoidosis cannot be definitively determined, nivolumab is a possible culprit. This case highlights the importance of a broad differential diagnosis when a patient undergoing antineoplastic treatment develops mediastinal lymphadenopathy or hypercalcaemia.

Custom High Throughput Drug Sensitivity Assay Reveals Therapeutic Options for Chronic Myeloid Leukemia Patients Resistant to or Intolerant of Tyrosine Kinase Inhibitors

Introduction. Tyrosine kinase inhibitors (TKIs) have revolutionized chronic phase (CP) chronic myeloid leukemia (CML) care with many patients achieving major and deeper molecular responses. However, for those who are resistant to or do not tolerate the approved TKIs, there are few alternatives. We therefore developed a custom high throughput drug screen comprised of both FDA approved and investigational agents. Methods. Fifty-six samples (50 individual patients) have undergone testing in the drug sensitivity assay, for which a large fraction exhibited resistance to approved agents. The Quellos High Throughput Core Laboratory's Cancer Drug Sensitivity has been CLIA approved for leukemia since 2015. Blood and bone marrow samples were obtained from CML patients with written informed consent. Mononuclear cells were isolated by density depletion. The myeloid population was obtained by lineage depletion of non-myeloid cells using magnetic beads and antibodies to erythroid lineage (CD235a), T (CD3) and B (CD19) lymphocytes, and NK (CD56) cells. Flow cytometry confirmed successful enrichment of the myeloid cell population. Cells were plated on extracellular matrix coated 384 well plates to test under conditions of adhesion mediated chemotherapy resistance. Initially, the assay was comprised of 32 drugs (11 patients) selected based on published activity in CML and resistant CML. The assay was then expanded to 64 drugs. Compounds are added (ranging from 5 pM to 100 μM) to patient samples using the CyBio CyBi-Well Vario and incubated at 37°C, 5% CO2 for 72 hours, then viability is assessed by CellTiterGlo. IC50s and AUCs are calculated for each drug using XLFit (IDBS) and a standard 4 parameter logistical model. Transcriptome analysis is planned for these samples. Results. Clinical characteristics are shown in Table 1. Mean and median BCR-ABL1 transcripts were 69% and 70% in diagnosis samples and 63% and 55% in resistant samples, respectively (P=0.607). ABL mutations were present in 5 patients (M244V, T315I, F359I). Additional myeloid mutations were present in 5 of 6 evaluable advanced phase samples, 4 of 17 evaluable diagnostic samples, and 3 of 10 evaluable resistant samples and included ASXL1, DNMT3A, IDH1, JAK2V617F, NRAS, RUNX1, and TET2. Figure 1 illustrates the breadth of sensitivity to agents in the assay. Figure 2 is a heat map of area under the curve (AUCs) illustrating the unique drug sensitivity patterns for all patients, with unsupervised clustering. For new diagnosis patients, the TKIs imatinib, dasatinib, nilotinib, bosutinib, and ponatinib ranked in the top 8 drugs. For primary resistant patients, the IC50 values for imatinib, nilotinib, bosutinib, and ponatinib were higher than the new diagnosis patients. For example, for ponatinib, the mean IC50 was 402.6 ± 354.7 X 10 E-9 M for primary resistant samples vs. 1.65 ± 0.45 X 10 E-9 M for diagnosis group, p=0.015 (Welch t test), or about 250-fold higher (less sensitive). In accelerated and blast phase samples drugs with IC50 values lower than 0.1 µM, a range that could correlate with in vivo drug response, were identified for all patients (range, 3-20 drugs per patient). Top candidates included proteasome and kinase inhibitors. In 2 patients harboring NRAS mutations, IC50 for trametinib was less than 0.1 µM as compared to patients without NRAS mutations, where the IC50s were higher. Clinical outcomes are available for nearly all patients. Although the study was not designed to select next-line TKI therapy in resistant patients, drug profiling was informative in many cases. Data for 7 resistant patients are shown in Table 2. For example, CML-012 had the lowest IC50 value (indicating most sensitive) for dasatinib, 4.1 X 10E-8 M and responded to dasatinib after failing imatinib (IC50 8.4 X 10E-7M). CML-003 did not respond to bosutinib (IC50 1.2 X 10E-6M) and did respond to dasatinib (IC50 1.2 X 10E-7M). CML-056 did not respond to nilotinib (IC50 1.4 X 10E-6M), dasatinib (IC50 6.9 X 10E-4M), or ponatinib (IC50 1.0 X 10E-6M). Notably, in all resistant patient samples we identified drugs with IC50 values lower than 0.1 µM. These therapeutics can be prioritized for further evaluation, either alone or in combination with TKIs, in resistant CML patients. Conclusion. In vitro drug sensitivity testing provides data for potential agents for patients with resistance or intolerance to FDA approved TKIs, or those that have entered accelerated phase or blast phase. Figure 1 Figure 1. Disclosures Oehler: Blueprint Medicines: Consultancy; Takeda: Consultancy; Pfizer: Research Funding; OncLive: Honoraria; BMS: Consultancy. Becker: Abbie: Research Funding; SecuraBio: Research Funding; Cardiff Oncology: Research Funding; Pfizer: Research Funding; BMS: Research Funding; CVS Caremark: Consultancy; Glycomimetics: Research Funding. OffLabel Disclosure: We developed a custom high throughput drug screen comprised of both FDA approved and investigational agents

CTNI-02. NERATINIB FOR TREATMENT OF LEPTOMENINGEAL METASTASES FROM HER2-POSITIVE BREAST CANCER IN EXTENDED ACCESS PROGRAM: PRELIMINARY RESULTS

INTRODUCTION The aim of the study was to evaluate the activity of neratinib in LM from HER2-positive BC after the failure of multiple lines of treatment. PATIENTS AND METHODS Inclusion criteria were as follows: age ≥ 18 years; histological diagnosis of primary HER2-positive BC; newly-diagnosed LM (LANO criteria); KPS ≥ 60; coexistence of BM that have or not received radiotherapy; life expectancy ≥ 3 months; previous drugs, including capecitabine, trastuzumab, T-DM1, pertuzumab, and hormone therapy, were allowed, with the exclusion of lapatinib or other investigational agents. Neratinib was administered 240 mg daily continuously. Primary endpoint was the OS. Secondary endpoints were progression-free survival (PFS), neurological benefit, radiological response rate, and tolerability. RESULTS Nine patients with LM have been enrolled with a median age of 44 years, and a median KPS of 80. Median time since LM onset from the diagnosis of primary BC was 42 months, and patients underwent a median number of adjuvant treatments before LM of 3. Three patients developed LM alone, and other 6 had LM associated with multiple BM. Six-months and 1-year OS were 66.7% and 22.3%, respectively, with a median OS of 8 months (95%CI 3-13*). Median PFS was 3.5 months (95%CI 2-6) after the start of treatment. A neurological improvement was reported in 2/9 patients (22.2%), while in other 4/9 patients (44.5%) was achieved a neurological stabilization lasting for a median time of 5 months (95%CI 2-19). The best radiological response was a stable disease in 5/9 patients (55.6%), while no complete or partial were achieved according to LANO criteria. A CSF clearance was observed in 1 patient only (11.1%). Grade III-IV adverse events were not reported, and 2 patients only (22.2%) had mild diarrhea correlated with neratinib. CONCLUSIONS Neratinib might be a safe and effective treatment in LM from heavily pretreated HER2-positive BC.

Remote Delivery of Motor Function Assessment and Training for Clinical Trials in Neuromuscular Disease: A Response to the COVID-19 Global Pandemic

Clinical outcome assessments of function or strength, assessed by physical therapists, are commonly used as primary endpoints in clinical trials, natural history studies and within clinics for individuals with neuromuscular disorders. These evaluations not only inform the efficacy of investigational agents in clinical trials, but also importantly track disease trajectory to prospectively advise need for equipment, home and work modifications, and other assistive devices. The COVID-19 pandemic had a global impact on the safety and feasibility of in-person visits and assessments, necessitating rapid development of mitigation strategies to ensure ongoing collection of key clinical trial endpoints and access to expert clinical care despite travel restrictions. Physical therapists who are expert in neuromuscular disorders working across clinics, countries, and clinical trials developed initial guidelines and methods for the suitability and feasibility of performing remote evaluations. A number of Sponsors introduced amendments to their study protocols to enable remote evaluations, supported by live video streaming of the assessment to their local clinical evaluators. Similarly, application of these techniques to clinical telemedicine enabled objective evaluations for use in payer discussions, equipment procurement, and general access to expert physical therapy services. Here we report on our methodology for adapting current practices to remote testing and considerations for remote evaluations.