BARCELONA, Spain—With the ancient Gothic Quarter looming near the site of the high-tech 26th EORTC-NCI-AACR Symposium on Molecular Targets and Cancer Therapeutics, Myriad Genetics announced biopharmaceutical company TESARO will use Myriad’s myChoice HRD companion diagnostic (CDx) to identify tumor tissue with a deficiency in homologous recombination—good news for the future of patients suffering from a resistant form of ovarian cancer.
Under the terms of the agreement, Waltham, Mass.-based TESARO will utilize Myriad’s test to enrich the target population for potential responders to niraparib, while Myriad provides the testing services and pursues the necessary regulatory approvals in support of TESARO’s development of niraparib as a therapy used for treating ovarian cancer.
In addition, Dr. Paul Haluska, Jr., associate professor of oncology at the Mayo Clinic, presented new data before the Barcelona symposium, demonstrating that Myriad’s myChoice HRD (homologous recombination deficiency) score is predictive of niraparib sensitivity in patient-derived xenograft models of ovarian cancer.
The companies have not disclosed the financial terms of the deal.
Mary Lynne Hedley, president and chief operating officer of TESARO, stated in a news release, “Myriad’s myChoice HRD diagnostic test identifies the inherent biology of the tumor and differentiates tumors with homologous repair deficiencies from those without such deficiencies. Niraparib sensitivity in patient-derived xenograft models is associated with HRD status as defined by the myChoice HRD test.”
“TESARO is developing niraparib for several tumor types, and we have two Phase 3 trials ongoing in patients with ovarian cancer and breast cancer,” TESARO CEO Lonnie Moulder tells DDNews. “Data have shown that patients who respond to PARP inhibitors often have tumors with certain DNA repair deficiencies—such as BRCA mutations—and who may be more likely to respond to treatment with niraparib.”
While TESARO “is responsible for all aspects of niraparib development, Myriad will be responsible for development of the diagnostic test,” he adds. “We believe that niraparib has the potential to be a meaningful advancement in the treatment of patients with ovarian cancer, breast cancer and potentially other tumors, such as small cell lung cancer.”
Ron Rogers, executive vice president of corporate communications at Myriad, spoke to DDNews about DNA-damaging agents and the importance of strategic collaborations that set the stage for new discoveries.
“DNA-damaging agents target and interrupt the DNA pathway in tumor cells, which result in the tumor cells dying,” Rogers said. “Patients who have tumors that lack the ability to repair the DNA may be more likely to respond to DNA-damaging agents like the platinum-based therapies or PARP (poly-ADP ribose polymerase) inhibitors.”
“Companion diagnostic collaborations with innovative partners are integral to our long-term research strategy, and we place a high value on all of pharmaceutical company collaborations,” Rogers explains. “Additionally, we’re committed to being a leader in personalized medicine for cancer patients. In the case of TESARO, our goal is to combine our strengths to better understand the underlying biology of cancer—and to drive the development of anti-cancer therapies.”
“We currently are partnering with more than 20 pharmaceutical companies,” he adds. “Our collaborations include DNA sequencing, RNA analysis, proteomics and in some instances we combine all three of these technologies.”
Myriad is “committed to being a leader in companion diagnostics that help target or tailor a treatment plan for patients,” Rogers says. “Studies are underway, and last month we announced an expansion of our research collaboration with TESARO.”
Jerry Lanchbury, chief scientific officer at Myriad, stated in a news release about that deal that “We are excited to be expanding our collaboration with TESARO as we strongly believe new diagnostics such as myChoice HRD, combined with targeted therapies such as niraparib, have the potential to significantly improve patient care.”
Myriad’s myChoice HRD CDx “utilizes three proprietary measures to assess the genomic scar associated with the loss of DNA repair, and has been shown in multiple clinical studies to be the most comprehensive predictor of tumor response to DNA damaging agents such as niraparib,” Lanchbury said.
Myriad first announced a collaboration with TESARO last year, on March 24 at Myriad’s U.S. headquarters in Salt Lake City, stating TESARO would use Myriad’s novel HRD test to identify tumor types that may respond to its investigational PARP inhibitor, niraparib, then in Phase 3 clinical development.
“The biology of cancer is complex, and increasingly the goal of oncology is to use a companion diagnostic to pair a tumor type with the targeted activity of a specific medicine,” Lanchbury said. “Prior studies have shown that only a subset of patients will respond to PARP inhibitors. HRD is the most comprehensive test to identify those patients who might respond to treatment.”
Myriad estimates the global market for an HRD test could exceed $3 billion as oncologists move toward personalized medicine and targeted therapies.
“As an innovation-focused company, we are leading the way in developing breakthrough companion diagnostics that have the potential to create significant value for patients and physicians,” Lanchbury said. “We also strive to be the research partner of choice.”
Companion diagnostics continue to be developed to identify patients most likely to benefit from specific treatments based on their own genetic makeup and biology and “hold tremendous promise in the treatment of diseases such as rheumatoid arthritis and other autoimmune disorders, cancer and diabetes,” according to Myriad.
In the recent study showing the CDx’s utility, patient-derived xenografts were created from more than 100 high-grade serious ovarian cancer tumor samples, Myriad reported.
HRD testing was performed on each sample using myChoice HRD to define HRD status, detect BRCA 1 and 2 mutations and identify hypermethylation of BRCA genes. Approximately half of these models were HRD-positive and are being evaluated for sensitivity to niraparib in vivo.
Preliminary data from treated models indicate all models that responded to niraparib treatment had an HRD score above the predetermined cutoff value, and included both BRCA mutant and BRCA wild-type tumors. Evaluation of niraparib sensitivity across the full set of selected models is ongoing.
Niraparib is an orally active and potent PARP, inhibitor. A Phase 1/2 monotherapy study of niraparib has been completed in more than 100 patients with advanced solid tumors. Two Phase 3 trials are currently ongoing to evaluate a single oral dose of niraparib as a maintenance therapy for patients with ovarian cancer and as a treatment for patients with BRCA-positive breast cancer.