Scott J. Antonia

Lung cancer is the leading cause of cancer-related mortality worldwide, with non-small cell lung cancer (NSCLC) accounting for over 85% of all cases. Until recently, chemotherapy – characterized by some benefit but only rare durable responses – was the only treatment option for patients with NSCLC whose tumors lacked targetable mutations. By contrast, immune checkpoint inhibitors have demonstrated distinctly durable responses and represent the advent of a new treatment approach for patients with NSCLC. Three immune checkpoint inhibitors, pembrolizumab, nivolumab and atezolizumab, are now approved for use in first- and/or second-line settings for selected patients with advanced NSCLC, with promising benefit also seen in patients with stage III NSCLC. Additionally, durvalumab following chemoradiation has been approved for use in patients with locally advanced disease. Due to the distinct features of cancer immunotherapy, and rapid progress in the field, clinical guidance is needed on the use of these agents, including appropriate patient selection, sequencing of therapies, response monitoring, adverse event management, and biomarker testing. The Society for Immunotherapy of Cancer (SITC) convened an expert Task Force charged with developing consensus recommendations on these key issues. Following a systematic process as outlined by the National Academy of Medicine, a literature search and panel voting were used to rate the strength of evidence for each recommendation. This consensus statement provides evidence-based recommendations to help clinicians integrate immune checkpoint inhibitors into the treatment plan for patients with NSCLC. This guidance will be updated following relevant advances in the field.

Jung CY, et al. Tuberc Respir Dis. 2018 Jan;81(1):29-41. https://doi.org/10.4046/trd.2017.0120

Background The combination of CTLA-4 and PD-L1 inhibitors has a manageable adverse effect profile, although rare immune-related adverse events (irAE) can occur. Case presentation We describe an autoimmune polymyositis following a partial response to combination tremelimumab and durvalumab for the treatment of recurrent lung adenocarcinoma. Radiography revealed significant reduction in all metastases; however, the patient developed progressive neuromuscular hypoventilation due to lymphocytic destruction of the diaphragmatic musculature. Serologic testing revealed a low level of de novo circulating antibodies against striated muscle fiber. Immunohistochemistry revealed type II muscle fiber atrophy with a mixed CD8⁺ and CD4⁺ lymphocyte infiltrate, indicative of inflammatory myopathy. Conclusions This case supports the hypothesis that muscle tissue is a target for lymphocytic infiltration in immune checkpoint inhibitor-associated polymyositis. Further insights into the autoimmune mechanism of PM will hopefully contribute to the prevention and treatment of this phenomenon.

Introduction: Advanced non-small cell lung cancer (NSCLC) is a challenging oncological problem. Following standard initial therapy, disease progression will typically develop. Patients with relapsed or refractory disease are left with limited treatment options. The advent of nivolumab, a monoclonal antibody against Program Death-1 (PD-1), has substantially changed the outlook for such patients. Area covered: Nivolumab is the first checkpoint immunotherapeutic agent to gain regulatory approval for NSCLC. By enabling host immune-mediated cytotoxic activity against tumor cells, nivolumab induces a partial or complete tumor response in 15–20% of patients, regardless of number of previous lines of anti-cancer therapy. Nivolumab-related adverse effects are generally milder and less frequent than those observed with conventional cytotoxic chemotherapy. Although immune-related adverse events such as fatal pneumonitis have been reported with nivolumab therapy, most adverse events are reversible with a prompt immunosuppression. Studies investigating nivolumab in combination with other agents are ongoing. Expert commentary: Nivolumab represents a significant breakthrough in the treatment of advanced NSCLC. Its therapeutic role for NSCLC may soon expand to include consolidation or maintenance setting. Furthermore, several clinical trials investigating the combination of nivolumab with other immunologic or non-immunologic treatments are ongoing and these will likely result in additional roles of nivolumab in NSCLC.

Anti-fibrotic drugs such as pirfenidone have been developed for the treatment of idiopathic pulmonary fibrosis. Because activated fibroblasts in inflammatory conditions have similar characteristics as cancer-associated fibroblasts (CAFs) and CAFs contribute actively to the malignant phenotype, we believe that anti-fibrotic drugs have the potential to be repurposed as anti-cancer drugs. The effects of pirfenidone alone and in combination with cisplatin on human patient-derived CAF cell lines and non-small cell lung cancer (NSCLC) cell lines were examined. The impact on cell death in vitro as well as tumor growth in a mouse model was determined. Annexin V/PI staining and Western blot analysis were used to characterize cell death. Synergy was assessed with the combination index method using Calcusyn software. Pirfenidone alone induced apoptotic cell death in lung CAFs at a high concentration (1.5 mg/mL). However, co-culture in vitro experiments and co-implantation in vivo experiments showed that the combination of low doses of cisplatin (10 μM) and low doses of pirfenidone (0.5 mg/mL), in both CAFs and tumors, lead to increased cell death and decreased tumor progression, respectively. Furthermore, the combination of cisplatin and pirfenidone in NSCLC cells (A549 and H157 cells) leads to increased apoptosis and synergistic cell death. Our studies reveal for the first time that the combination of cisplatin and pirfenidone is active in preclinical models of NSCLC and therefore may be a new therapeutic approach in this disease.

Immuno-oncology is an evolving treatment modality that includes immunotherapies designed to harness the patient's own immune system. This approach is being studied for its potential to improve long-term survival across multiple tumor types. It is now important to determine how immunotherapies may be most effectively used to achieve the best possible patient outcomes. Combining or sequencing immunotherapies that target distinct immune pathways is a logical approach, with the potential to further enhance the magnitude of the antitumor immune response over single agents. Early clinical data in patients with melanoma treated with two immune checkpoint inhibitors, ipilimumab and nivolumab, suggest support for this combination approach. Numerous other combination approaches are being evaluated in early-phase clinical trials; however, their clinical activity remains unknown. Clinical experience to date has shown that when combining an immuno-oncology agent with an existing therapeutic modality, it is important to determine the optimal dose, schedule, and sequence. Clin Cancer Res; 20(24); 6258–68. ©2014 AACR.

Recently it has become clear that the cost associated with the Warburg effect, which is inefficient production of ATP, is offset by selective advantages that are produced by resultant intracellular metabolic alterations. In fact tumors may be addicted to the Warburg effect. In addition these alterations result in changes in the extracellular tumor microenvironment that can also produce selective advantages for tumor cell growth and survival. One such extracellular alteration is increased adenosine concentrations that have been shown to impair T cell mediated rejection and support angiogenesis. The expression of the A2A receptor in non-small cell cancer (NSCLC) tissues, cell lines and cancer associated fibroblasts (CAF) was determined by performing immunohistrochemistry and immunoblot analysis. The efficacy of the A2A receptor antagonists in vivo was evaluated in a PC9 xenograft model. To determine the mode of cell death induced by A2A receptor antagonists flow cytometry, immunoblot, and cytotoxic analysis were performed. We found that a significant number of lung adenocarcinomas express adenosine A2A receptors. Antagonism of these receptors impaired CAF and tumor cell growth in vitro and inhibited human tumor xenograft growth in mice. These observations add to the rationale for testing adenosine A2A receptor antagonists as anticancer therapeutics. Not only could there be prevention of negative signaling in T cells within the tumor microenvironment and inhibition of angiogenesis, but also an inhibitory effect on tumor-promoting, immunosuppressive CAFs and a direct inhibitory effect on the tumor cells themselves.

Soft tissue sarcomas are rare neoplasms, with approximately 9000 new cases in the USA every year. Unfortunately, during the past two decades, there has been little progress in the treatment of metastatic soft tissue sarcomas beyond the standard approaches of surgery, chemotherapy and radiation. Immunotherapy is a modality complementary to conventional therapy. It is appealing because functional antitumor activity could affect both local–regional and systemic disease, and act over a prolonged period of time. In this report, we review immunotherapeutic investigative strategies that are being developed, including several tumor vaccine, antigen vaccine and dendritic cell vaccine strategies.