Researchers from the MD Anderson Cancer Center will present at the American Society of Clinical Oncology's annual meeting later this week the results from two studies showing that Ipsogen’s Genomic Grade index can help predict which breast cancer patients will respond to chemotherapy, the company said last week.
The molecular diagnostic company, which is focused on developing products for the blood and breast cancer market, licensed the worldwide exclusive rights to the Genomic Grade index from the Université Libre de Bruxelles, Belgium, in January and plans to market the index alongside its breast cancer diagnostics, which are slated to debut later this year.
Invented by the Bordet Institute's Christos Sotiriou and Martine Piccart, and Mauro Delorenzi from the Swiss Institute for Cancer Research, the Genomic Grade index is a 97-gene measure of histologic tumor grade. In clinical studies the index was found to have better prognostic and classification value in analyzing tumors than histological analysis.
The first ASCO study, to be presented by W. F. Symmans and colleagues from the MD Anderson Cancer Center and the Institut Bordet, sought to learn whether the Genomic Grade index is a predictive marker for chemotherapy response in HER2-normal breast cancer.
In the study, 229 patients with HER2-normal breast cancer were treated with the commonly used regimen T/FAC — paclitaxel, 5-fluoruracil, doxorubicin, and cyclophosphamide — followed by surgery. The researchers collected gene-expression data using Affymetrix GeneChip technology.
Researchers concluded that ER-positive and ER-negative patients who measured higher on the Genomic Grade index were more sensitive to T/FAC, and thus responded better to the regimen, than women who ranked lower on the scale.
The findings emboldened Ipsogen to announce that the Genomic Grade index “is predictive for increased sensitivity to T/FAC chemotherapy” in this subset of patients … [and] can be combined with ER and nodal status to predict which patients will not respond to preoperative T/FAC chemotherapy in 72 percent of cases.”
"This work demonstrates that high genomic grade, as a robust measure of proliferation in the tumor cells, is associated with benefit from chemotherapy,” Symmans, lead author of the study and an associate professor of pathology at MD Anderson Cancer Center, said in a statement issued by Ipsogen. “In the context of other published work it underlines the association between high tumoral proliferation rate and chemosensitivity, endocrine insensitivity, and worse prognosis."
Ipsogen is “fully committed to rapidly translat[ing] these clinical findings into regulatory-approved and reimbursed test offerings to European and American patients.”
The second ASCO paper, to be presented by L. Pusztai and colleagues from MD Anderson, discusses a genome-wide microarray study combining the Genomic Grade index with the 200-gene endocrine-sensitivity index to predict both chemotherapy response and hormone therapy response in breast cancer.
In the study, researchers generated gene expression profiling results with Affymetrix U133A gene chips on 198 stage I-II, lymph node-negative patients with HER2-normal breast cancer who received no systemic adjuvant therapy and on 229 stage I-III, HER-2 normal breast cancer patients who all received preoperative paclitaxel/FAC chemotherapy. Agendia's MammaPrint test provided prognostic prediction results for 198 cases.
With the help of the Genomic Grade index and the endocrine sensitivity index, researchers concluded that those patients predicted to be at low risk for recurrence are mainly sensitive to endocrine therapy. However, approximately 12 percent of patients in the study may also be sensitive to chemotherapy and between 40 percent and 50 percent of high-risk patients are predicted to be insensitive to existing therapies.
“Simultaneous prediction of risk of recurrence and sensitivity to endocrine and chemotherapies is currently possible and may allow more personalized treatment decisions in the future,” the researchers concluded.
"This study further confirms the potential of Ipsogen's pipeline strategy of multiple high-resolution genomic measurements to improve the decision tree of chemotherapeutic options in breast cancer,” Ipsogen CEO Vincent Fert said in a statement.
Although Ipsogen did not reveal any details about its plan to launch the breast cancer tests later this year, the company has said in the past that when used with diagnostic tests, the Genomic Grade index would improve a physician’s ability to predict chemotherapy response.
“One key indication of the [Genomic Grade index] would be to select patient who would respond to chemo pre- and postoperative,” Jean-Marc Le Doussal, the director of Ipsogen's breast cancer program, told Pharmacogenomics Reporter last week.
Since approximately 75 percent of breast cancer patients are HER2 normal, a breast cancer diagnostic that can more accurately predict which patients will benefit from chemotherapy treatment with the aid of the Genomic Grade index could have a sizable market.
“You will soon learn more” about Ipsogen's breast cancer diagnostic tests, Le Doussal said.
Fert said earlier this year in a statement discussing the Genomic Grade index that Ipsogen is “fully committed to rapidly translat[ing] these clinical findings into regulatory-approved and reimbursed test offerings to European and American patients.”
Studies presented last year at ASCO's annual meeting showed that Genomic Grade can be measured by DNA microarray and multiplex PCR technologies.
And at the St. Gallen Breast Cancer Conference in March 2007, Piccart presented results of a meta-analysis of breast cancer prognostic genomic signatures showing that genomic measures of tumor grade were a commonly applied technique.
“The genomic field was quite [chaotic] where each actor tries to sell its own prognostic factor in breast cancer,” Ipsogen CEO Vincent Fert has said in the past. “But all these prognostic factors overlap and the common factor is the grade, as pathologists know.”
According to Ipsogen, the index can help oncologists improve treatment decisions in about 50 percent of breast cancer patients.