Conversion of Platinum-Etoposide-Resistant to Sensitive SCLC after Treatment with the Epi-Immunotherapeutic RRx-001: A Case Report.

BACKGROUND: The response to first-line platinum doublets (cisplatin/etoposide) in small-cell lung cancer (SCLC) predicts the probability of subsequent response to second-line therapy. In general, the longer-lived the responses in first line, the better the outcome in second line, with the opposite prognosis for shorter-lived responses. Resistant SCLC is defined as relapse within 90 days of platinum-doublet treatment, and predictably correlates with shortened survival compared with sensitive disease, defined as relapse after 90 days. CASE REPORT: We present a patient with platinum-resistant SCLC that was rechallenged with cisplatin/etoposide in the context of the clinical trial TRIPLE THREAT (NCT02489903) after treatment with, and progression on, the resistance-reversing anticancer agent RRx-001. CONCLUSION: The prolonged partial response of this platinum-resistant SCLC to reintroduced carboplatin/etoposide after RRx-001 belies and contradicts the prevailing orthodoxy in oncology that rechallenge with chemotherapy after the emergence of resistance is an exercise in futility and risk, which potentially exposes patients to toxicity without benefit.

Partial Response in an RRx-001-Primed Patient with Refractory Small-Cell Lung Cancer after a Third Introduction of Platinum Doublets.

Small-cell lung cancer (SCLC), initially exquisitely sensitive to first-line cisplatin/etoposide, invariably relapses and acquires a multidrug chemoresistant phenotype that generally renders retreatment with first-line therapy both futile and counterproductive. This report presents the case of a 77-year-old Caucasian male with extensive-stage refractory SCLC who was restarted on platinum doublets as part of a clinical trial called TRIPLE THREAT (NCT02489903) involving pretreatment with the epi-immunotherapeutic agent RRx-001, and who achieved a partial response after only 4 cycles. The patient had received a platinum drug twice before, in 2009 for a diagnosis of non-small-cell lung cancer (squamous cell carcinoma) and in 2015 for SCLC, suggesting that RRx-001 pretreatment may sensitize or resensitize refractory SCLC patients to first-line chemotherapy.

Partial response to carboplatin in an RRx-001 pretreated patient with EGFR-inhibitor-resistance and T790M-negative NSCLC.

Few therapeutic options are available for T790M-negative non-small cell lung cancer (NSCLC) after failure of primary epidermal growth factor receptor-tyrosine kinase inhibitors (EGFR-TKIs) and chemotherapy. This report presents the case of a 71-year-old Asian female never smoker with EGFR mutated T790M negative non squamous cell lung cancer (NSCLC) pre-treated with the experimental epi-immunotherapeutic agent, RRx-001, that re-responded to single agent carboplatin after failure of platinum doublets, TKIs, pemetrexed and nivolumab. The management of advanced EGFR mutation-positive NSCLC is briefly reviewed herein and the emerging paradigm of episensitization, which contradicts the long-standing and widely accepted tenet about the immutability of resistance and the futility of therapeutic rechallenge, is introduced as a strategy to avert treatment failure and thereby stave off deterioration and death.

Immune Reactivity and Pseudoprogression or Tumor Flare in a Serially Biopsied Neuroendocrine Patient Treated with the Epigenetic Agent RRx-001.

Neuroendocrine tumors (NETs) are grouped together as a single class on the basis of histologic appearance, immunoreactivity for the neuroendocrine markers chromogranin A and synaptophysin, and potential secretion of hormones, neurotransmitters, neuromodulators and neuropeptides. Nevertheless, despite these common characteristics, NETs differ widely in terms of their natural histories: high-grade NETs are clinically aggressive and, like small cell lung cancer, which they most closely resemble, tend to respond to cisplatin and etoposide. In contrast, low-grade NETs, which as a rule progress and behave indolently, do not. In either case, the treatment strategy, apart from potentially curative surgical resection, is very poorly defined. This report describes the case of a 28-year-old white male with a diagnosis of high-grade NET of undetermined primary site metastatic to the lymph nodes, skin and paraspinal soft tissues, treated with the experimental anticancer agent RRx-001, in the context of a phase II clinical trial called TRIPLE THREAT (NCT02489903); serial sampling of tumor material through repeat biopsies demonstrated an intratumoral inflammatory response, including the amplification of infiltrating T cells, which correlated with clinical and symptomatic benefit. This case suggests that pseudoprogression or RRx-001-induced enlargement of tumor lesions, which has been previously described for several RRx-001-treated patients, is the result of tumoral lymphocyte infiltration.

RRx-001 in Refractory Small-Cell Lung Carcinoma: A Case Report of a Partial Response after a Third Reintroduction of Platinum Doublets.

RRx-001 is a pan-active, systemically nontoxic epigenetic inhibitor under investigation in advanced non-small cell lung cancer, small-cell lung cancer and high-grade neuroendocrine tumors in a Phase II clinical trial entitled TRIPLE THREAT (NCT02489903), which reexposes patients to previously effective but refractory platinum doublets after treatment with RRx-001. The purpose of this case study is first to report a partial response to carboplatin and etoposide in a patient with small-cell lung cancer pretreated with RRx-001, indicating episensitization or resensitization by epigenetic mechanisms, and second to discuss the literature related to small-cell lung cancer and episensitization.

RRx-001-Induced Tumor Necrosis and Immune Cell Infiltration in an EGFR Mutation-Positive NSCLC with Resistance to EGFR Tyrosine Kinase Inhibitors: A Case Report.

We present the case of a 49-year-old male with metastatic epidermal growth factor receptor (EGFR) mutation-positive adenocarcinoma of the lung that continues to outlive stage IV diagnosis of non-small cell lung cancer after treatment with RRx-001, an experimental anticancer agent with epigenetic and immunologic activity, in the context of a phase II clinical trial called TRIPLE THREAT. Currently, no adequate treatment options exist for patients with EGFR mutation-positive tumors who have failed a 1st-generation tyrosine kinase inhibitor (erlotinib or gefitinib) treatment and do not develop a resistant mutation. Biopsy of a large pancreatic metastasis after RRx-001 demonstrated extensive necrosis with CD3+ and CD8+ immune cell infiltration that appears to correlate with prolonged survival despite end-stage disease. These results suggest that the mode of action of RRx-001 is related to immune stimulation in addition to epigenetic inhibition.

Partial Response to Platinum Doublets in Refractory EGFR-Positive Non-Small Cell Lung Cancer Patients after RRx-001: Evidence of Episensitization.

RRx-001, an experimental systemically non-toxic epi-immunotherapeutic agent, which potentiates the resensitization of resistant cancer cells to formerly effective therapies, is under active investigation in several clinical trials that are based on sequential or concomitant rechallenge to resistant first- or second-line regimens. One of these trials is designated TRIPLE THREAT (NCT02489903), because it explores the conditioning or priming effect of RRx-001 on three tumor types - non-small cell lung cancer (NSCLC), small cell lung cancer and high-grade neuroendocrine tumors - prior to re-administration of platinum doublets. In follow-up to a recent case study, which describes early monotherapeutic benefit with RRx-001 in a refractory EGFR-mutated NSCLC tumor, we present subsequent evidence of a radiological partial response to reintroduced platinum doublets after RRx-001. For the 50% of patients with EGFR-mutated NSCLC who progress on EGFR-tyrosine kinase inhibitors (without evidence of a T790M mutations) as well as platinum doublets and pemetrexed/taxane, no other clinically established treatment options exist. A retrial of these therapies in EGFR-positive NSCLC patients via priming with epigenetic agents such as RRx-001 constitutes a strategy to 'episensitize' tumors (i.e. reverse resistance by epigenetic means) and to extend overall survival.

Flushing Out Carcinoid Syndrome: Beneficial Effect of the Anticancer Epigenetic Agent RRx-001 in a Patient with a Treatment-Refractory Neuroendocrine Tumor.

Neuroendocrine tumors (NET) are a heterogeneous group of neoplasms defined by the presence of cells with secretory granules and the potential to produce and release high levels of vasoactive peptides into the circulation, leading to severe flushing and diarrhea, which may adversely affect quality of life. This report presents the case of a 64-year-old man with chronic refractory diarrhea due to pulmonary NET treated with the experimental anticancer agent RRx-001 in a phase II trial called TRIPLE THREAT with subsequent resolution of his diarrhea.