Chemosensitivity Tests (CSRA)

Functional Profiling Leads to Identification of Accurate Genomic Findings

Robert A. Nagourney, M.D.
Medical & Laboratory Director
Rational Therapeutics

The 2013 American Society of Clinical Oncology annual meeting, held May 31 – June 1, in Chicago, afforded the opportunity to report three studies.

The first, “An examination of crizotinib activity in human tumor primary culture micro-spheroids isolated from patients with advanced non-small cell lung cancer,” reports our experience using the EVA-PCD platform to examine the drug crizotinib. This small molecule originally developed as an inhibitor of the oncogenic pathway MET, was later found to be highly active in a subset of cancer patients who carried a novel gene rearrangement for anaplastic lymphoma kinase (ALK). It was this observation that lead to the drug (sold under the name Xalkori) being approved for the treatment of advanced ALK positive lung cancer. The subsequent observation that this same drug inhibited yet another gene target known as ROS-1 found in a subset of lung cancer patients, has led to its use in this patient population.

Our exploration of crizotinib activity identified a series of patients who received the drug and responded dramatically. This included both ALK positive and ROS-1 positive patients. One patient however, appeared highly sensitive to the drug in our studies, but was found negative for the ALK gene rearrangement by genomic analysis. We repeated our functional analysis only to the find again, the same high degree of crizotinib sensitivity. I felt confident the patient should receive crizotinib, but at the time the drug was not yet commercially available and he didn’t qualify for the protocols, as he was ALK negative.

I scoured the country looking for a way to get the patient treated with crizotinib. From Sloan Kettering to UCLA, no one could help. And then, in collaboration with my abstract co-author Ignatius Ou from UC Irvine, we decided to repeat the ALK analysis. That proved to be a very good idea. For the patient was indeed positive for ALK gene rearrangement by second analysis and subsequently responded beautifully to a treatment for which he would not otherwise qualify. Once again, phenotype trumped genotype.

A final patient in the series represented a particularly interesting application of functional analysis. The patient, a young woman with an extremely rare pediatric sarcoma, had failed to respond to multiple courses of intensive chemotherapy and her family was desperate. As she approached the end of her third year in high school, it looked unlikely that she would reach her senior year. A portion of her tumor was submitted for analysis. The results confirmed relative resistance to chemotherapeutics, many of which she had already received and failed, but showed exquisite sensitivity to crizotinib. Indeed, our inclusion of crizotinib in the analysis reflected our intense effort to identify any activity for this previously refractory patient.

We reported our findings to the pediatric oncologist and encouraged them to consider an ALK rearrangement analysis, despite this particular pathway not being on anyone’s radar prior to our study. The result – a positive gene rearrangement. This led to a successful petition to the drug company for the use of this agent for an off-label indication. The response was prompt and dramatic, and remains durable to this day, nearly a year later. Again, the phenotypic analysis guided us to the correct genomic finding.

Note: Another of the functional cytometric profiling labs has reported out positive for Xalkori (crizotinib) killing tumor cells and killing endothelial cells, with absolutely brilliant responses, in some ALK translocation negative lung cancer patients.

Clinical application of human tumor primary culture analyses

The study reviewed the results of 67 patients from institutions across Brazil. Tumor samples were transported by overnight courier to California for drug response profiling. A broad array of tumors were included. The overall success rate provided actionable results in 62 of 67 patients (92 percent). More than 75 percent of the studies provided results for between 8 and 16 drugs and combinations with a median of 12 reported. Several strikingly good responses were observed, including novel combinations identified in the laboratory. This study confirms the feasibility of international collaboration and reflects the globalization of medical care delivery.

International collaboration in personalized medicine for the treatment of advanced and drug-refractory cancers: Clinical application of human tumor primary culture analyses.

Subcategory: Cytotoxic and Other Novel Agents

Session Type and Session Title: This abstract will not be presented at the 2013 ASCO Annual Meeting but has been published in conjunction with the meeting.

Abstract Number: e13562

Citation: J Clin Oncol 31, 2013 (suppl; abstr e13562)

Author(s): 

Fabricio Colacino Silva, Fernando C. Maluf, Antonio C. Buzaid, Robert Alan Nagourney, Nise Hitomi Yamaguchi, Paulo D'Amora, Steven Evans, Paula J Bernard, Federico Francisco; Hospital do Cancer Alfredo Abrao, Campo Grande, Brazil; Hospital Sirio-Libanes, São Paulo, Brazil; Hospital São José, São Paulo, Brazil; Rational Therapeutics, Long Beach, CA; Institute of Advances in Medicine and Hospital Albert Einstein, Sao Paulo, Brazil; Centro de Genomas, Sao Paulo, Brazil

Background:

Personalized oncology has advanced through genomic and proteomic platforms. BCR-abl; EGFr and ALK have provided drug-able targets and companion diagnostics in several diseases, yet many transforming events in humans are polygenic, complex and incompletely understood at a genomic level. Recognition that oncogenesis reflects changes in the cell and its micro environment has renewed interest in whole cell experimental models that capture native-state cell-cell, -stroma and -vascular signaling. Ex vivo analysis of programmed cell death (EVA/PCD) has been shown to correlate significantly with response, time to progression and survival (Nagourney, R. Curr. Treat Op Oncol, 2006).To explore EVA/PCD functional profiling in Brazil, hospital-based investigators, Centro de Genomas and Rational Therapeutics coordinated the transport of 67 surgical specimens for analyses.

Methods:

Dose-response curves using metabolic (ATP-content, mitochondrial) and morphologic endpoints, interpolated to LC50's and synergy by median-effect, were compared with databases to identify patient-specific profiles for cytotoxics, targeted agents and combinations. Reports provided day 7.

Results:

62/67 (92%) provided adequate tumor for analysis; 39 male (58%); 28 (42%) female; 6 chemo-naive and 61 previously treated. Results provided for < 8 drugs in 14/62 (22%); 8-16 drugs in 34/62 (54%) and > 16 drugs in 14/62 (22%). Of 22 tumor types, breast (8); Melanoma (8); NSCLC (8); ovary (7); pancreas (7) and sarcoma (4) predominated. EVA/PCD was used to select the most active combinations. Agents selected, response rates and durations are being tabulated and will be reported.

Conclusions:

The transport, processing and reporting of human tumor primary culture analyses is feasible, providing results in 92% of specimens and median of 12 drugs evaluated (range 4-32). Preliminary outcomes in these drug-refractory patients reveal that novel, often unexpected drug combinations (Everolimus and Lapatinib in triple negative breast) were identified and provided objective tumor responses, supporting EVA/PCD in therapy selection (personalized therapy) and drug development.

http://meetinglibrary.asco.org/content/117655-132