Medical oncology care amidst the COVID-19 pandemic at the National University Hospital in the Philippines.

COVID-19 has abruptly and radically changed the landscape of cancer care delivery throughout the world, including the Philippines. The Philippine General Hospital is the academic hospital of the University of the Philippines. Its cancer centre is a primary referral centre that takes care of Filipinos-many resource-constrained-that are burdened by malignancy. As the global pandemic challenges healthcare delivery, centres are forced to rethink how to care for their patients. This paper discusses how a national, academic, referral cancer institute in a low-middle income country is trying to meet the challenges of COVID-19.

Le morte du tumour: histological features of tumor destruction in chemo-resistant cancers following intravenous infusions of pathotropic nanoparticles bearing therapeutic genes.

The pathotropic targeting of therapeutic nanoparticles to cancerous lesions is an innovative concept that has recently been reduced to practice in clinical trials for the treatment of metastatic cancer. Previously, we reported that intravenous infusions of Rexin-G, a pathotropic nanoparticle (or vector) bearing a cyto-ablative construct, induced tumor regression, reduced tumor burden, and improved survival, while enhancing the overall quality-of-life of patients with otherwise intractable chemotherapy-resistant cancers. In this report, we describe the major histopathological and radiologic features that are characteristic of solid tumors under the destructive influences of Rexin-G administered as a single therapeutic agent. To further promote tumor eradication and enhance cancer survival, we explored the potential of an auxiliary gene transfer strategy, specifically intended to induce a localized cancer auto-immunization in addition to assisting in acute tumor destruction. This immunization strategy uses Rexin-G in combination with Reximmune-C, a tumor targeted expression vector bearing a granulocyte macrophage-colony stimulating factor (GM-CSF) gene. Intravenous infusions of Rexin-G were given first to induce apoptosis and necrosis in the metastatic tumor nodules, thus exposing tumor neo-antigens, followed by Reximmune-C infusions, intended to recruit immune cells discretely into the same compartments (or lesions). The intent of this two-step approach is to bring a complement of cells involved in humoral and cell-mediated immunity in close proximity to the immunizing tumor antigens in a concerted effort to assist in tumor eradication and to promote a cancer vaccination in situ. Herein, we also describe the distinctive histopathologic and immunocytochemical features of tumors in terminal cancer patients who received Rexin-G infusions in combination with Reximmune-C. In addition to documenting the first histological indications of clinical efficacy achieved by this novel personalized approach to cancer vaccination, we discuss new methods and strategies for advancing its therapeutic utility. Taken together with the clinical data, these histological studies serve as valuable landmarks for medical oncology, and as definitive benchmarks for the emerging field of cancer gene therapy.

Pathotropic nanoparticles for cancer gene therapy Rexin-G IV: three-year clinical experience.

Metastatic cancer is a life-threatening illness with a predictably fatal outcome, thereby representing a major unmet medical need. In 2003, Rexin-G became the world's first targeted injectable vector approved for clinical trials in the treatment of intractable metastatic disease. Uniquely suited, by design, to function within the context of the human circulatory system, Rexin-G is a pathotropic (disease-seeking) gene delivery system bearing a designer killer gene; in essence, a targeted nanoparticle that seeks out and selectively accumulates in metastatic sites upon intravenous infusion. The targeted delivery of the cytocidal gene to primary tumors and metastatic foci, in effective local concentrations, compels both cancer cells and tumor-associated neovasculature to self-destruct, without causing untoward collateral damage to non-target organs. In this study: i) we report the results of three distinctive clinical studies which demonstrate the initial proofs of concept, safety, and efficacy of Rexin-G when used as a single agent for advanced or metastatic cancer, ii) we introduce the quantitative foundations of an innovative personalized treatment regimen, designated the 'Calculus of Parity', based on a patient's calculated tumor burden, iii) we propose a refinement of surrogate end-points commonly used for defining success in cancer therapy, and iv) we map out a strategic plan for the accelerated approval of Rexin-G based on the oncologic Threshold of Credibility paradigm being developed by the Food and Drug Administration.

First clinical experience using a 'pathotropic' injectable retroviral vector (Rexin-G) as intervention for stage IV pancreatic cancer.

Metastatic or non-resectable (stage IV) pancreatic cancer has a rapidly fatal outcome (median survival: 3-6 months), thus making gene therapy a viable therapeutic option. The objectives of the clinical studies are to evaluate the safety/toxicity and potential anti-tumor response/efficacy of intravenous (i.v.) infusions of a 'pathotropic' retroviral vector bearing a cytocidal gene construct (Rexin-G) as a gene transfer intervention for stage IV pancreatic cancer. An intra-patient dose escalation regimen was used wherein increasing doses of Rexin-G were given i.v. daily for 8-10 days. Completion of this regimen was followed by a one-week evaluation period for toxicity, after which, the maximum tolerated dose of Rexin-G was administered for another 8-10 days. In a second protocol, i.v. Rexin-G was administered frontline for 6 days followed by 8 doses of weekly gemcitabine. The NIH Common Toxicity Criteria Vs.2 was used to assess toxicity, and the NCI-RECIST criteria and tumor volume measurements were used to evaluate potential anti-tumor responses. We report the results of the first 3 patients that participated in the studies. Rexin-G arrested tumor growth in 3 of 3 patients without experiencing dose-limiting toxicity. No bone marrow suppression, significant alterations in liver and kidney function, nausea and vomiting, mucositis or hair loss were observed. Two patients are alive with stable disease approximately 5 and 14 months from diagnosis, and 1 patient is alive with progressive disease 20 months from diagnosis. The encouraging results of this first clinical experience will guide the design and planning of phase I/II clinical trials to establish the safety and efficacy of Rexin-G as the first targeted injectable gene therapy vector for stage IV pancreatic cancer.