Originally published Nov. 7.
Myriad Genetics updated investors this week about the progress the company is making in its effort to transform its BRACAnalysis test into a companion diagnostic that identifies best responders to DNA-damaging drugs. The company also discussed launch plans for new tests in lung cancer and melanoma, and the adoption of its Prolaris prostate cancer test.
During its fiscal first quarter 2014 earnings call, Myriad officials said that the company's collaboration with AstraZeneca to market its PARP inhibitor olaparib with BRACAnalysis as a companion test is on track for a European launch by 2015.
The European Medicines Agency accepted AstraZeneca's marketing application for olaparib on September 30. "Olaparib has a potential of being the first commercially available PARP inhibitor, and may be on the market in Europe as early as January 2015," Myriad CEO Peter Meldrum said during the call.
In the US, Myriad filed its first investigational device exemption application for BRACAnalysis with the US Food and Drug Administration over the summer, and the agency has accepted the IDE filing. That application has enabled Myriad to use BRACAnalysis to detect best responders to olaparib in two Phase III trials. One study will investigate olaparib maintenance therapy in the first-line setting in ovarian cancer patients with BRCA mutations, and the second trial will assess the drug in platinum-sensitive, relapsed ovarian cancer patients who harbor these mutations. AstraZeneca is also investigating olaparib in breast cancer patients with BRCA mutations.
BRACAnalysis is currently Myriad's best-selling product, bringing in $149.6 million dollars in revenues during the first fiscal 2014 quarter, which accounts for 74 percent of the company's total revenues. However, Myriad is planning to phase out its hereditary cancer tests, including BRACAnalysis, and provide in their place the next-generation sequencing-based MyRisk Hereditary cancer panel. This transition is slated for completion by the summer of 2015.
However, the company does see continued utility for the BRACAnalysis test as a companion diagnostic. To this end, Myriad has announced collaborations with six drug developers advancing PARP inhibitors, half of which have now advanced their drugs into late-stage development. "While we believe the hereditary cancer market will rapidly shift to myRisk, we continue to believe that BRACAnalysis will enjoy strong demand as a companion diagnostic for PARP inhibitors and possibly DNA-damaging agents," Meldrum said.
Myriad has also filed an IDE application to use BRACAnalysis in Phase III trials involving BioMarin's PARP inhibitor for breast cancer BMN-673. "The BioMarin PARP inhibitor has exhibited strong potency, possibly due to its ability of trapping PARP onto the DNA, which is lethal to cancer cells," Meldrum said.
PARP inhibitors, such as BMN-673, inhibit PARP proteins from repairing DNA breaks in cells. Since patients with BRCA mutations already have an impaired ability to repair DNA, researchers are hoping that when given a PARP inhibitor, patients' cancer cells will be inundated with damaged DNA and die. Based on this hypothesis, a companion test that picks out which patients have BRCA mutations would help identify best responders to PARP inhibitors.
Another Rx/Dx partner for Myriad is Tesaro, which announced last quarter that it was initiating a Phase III trial to study its PARP inhibitor niraparib in ovarian cancer patients. "As with our other collaborators, Myriad is determining the BRCA status of all patients prior to their enrollment in Tesaro's Phase III clinical study," Meldrum said.
In this randomized Phase III trial, Tesaro is planning to compare niraparib again placebo in more than 350 platinum-sensitive ovarian cancer patients who either have a germline BRCA mutation or a tumor with high-grade serous histology. Researchers will measure how efficacious niraparib is as a maintenance therapy based on how long the drug prolongs progression-free survival compared to placebo. Investigators will also measure study participants' quality of life while on the drug.
In gauging the BRCA status of patients, researchers from Tesaro will also assess the concordance of "a candidate companion diagnostic test compared to centralized BRCA mutation test[ing]."
AstraZeneca conducted a similar comparison between Myriad's BRACAnalysis and Foundation Medicine's NGS-based test. In a Phase II subgroup analysis, AstraZeneca used Foundation's test to gauge somatic BRCA mutations and Myriad's test to gauge germline mutations. Both groups had similar outcomes on olaparib. In Phase III studies, however, AstraZeneca plans to only gauge germline mutations in patients using BRACAnalysis (PGx Reporter 6/4/2013).
During the first quarter, Myriad's companion diagnostic service revenues increased 54 percent to $9.5 million. In an effort to support its increasing activities in the companion testing space, Myriad has announced it will build a new lab at its Salt Lake City facility that will be specifically dedicated to this work. The lab build-out, Myriad has said, expands its non-exclusive partnership with AstraZeneca to study olaparib in Phase III studies with the help of BRACAnalysis.
In addition to studying BRACAnalysis as a companion test and launching its myRisk NGS test, Myriad plans to continue to diversify its test portfolio. In late October, the company launched its myPlan Lung Cancer test to early access customers with a list price of $3,400, and the firm said it will launch myPath Melanoma by the end of the calendar year.
As such, Myriad has begun to build the evidence base around the lung cancer and melanoma test. MyPlan Lung Cancer gauges 31 cell cycle proliferation genes and 15 housekeeping genes and yields a score that delineates the risk that a patient with a Stage I/II lung adenocarcinoma will die within five years after surgical resection of their tumor.
Researchers from Myriad, MD Anderson Cancer Center, and elsewhere published a validation study in Clinical Cancer Research that showed that the myPlan Lung Cancer score was the strongest predictor of cancer survival in early-stage patients compared to conventional factors such as age, stage of disease, gender, smoking status, and tumor size. Separately, the company recently presented data from another study at a major medical conference showing that when researchers used the myPlan test, they predicted five-year lung cancer mortality with more accuracy than when they used tumor staging alone.
MyPath Melanoma is a 23-gene panel test that Myriad will market as a tool to help doctors determine if a skin biopsy is benign or malignant. The company recently announced results from a verification study involving more than 450 skin biopsy samples showing that the test had a sensitivity of 89 percent and a specificity of 93 percent. Meldrum told investors during the call that myPath Melanoma represents a global market of over $800 million annually, and carries an average selling price of $1,500.
Another major focus at Myriad is to drive adoption of its Prolaris prostate cancer test. During the first quarter, Myriad reported that sample volumes from ordering physicians increased by 20 percent from the fourth quarter in fiscal year 2013.
Prolaris analyzes the expression of 31 cell cycle progression genes and 15 housekeeping genes, and yields a score that tells doctors if a patient is at risk for aggressive or indolent disease. In June, PGx Reporter reported that Myriad had received 3,000 orders for Prolaris from 350 urologists (PGx Reporter 6/12/2013).
The test, however, isn't yet covered for Medicare patients — and the majority of prostate cancer patients, around 60 percent, are covered under Medicare. To provide payors the necessary evidence for reimbursement, Myriad is conducting prospective studies, called PROCEED, in which researchers are gauging the degree to which the Prolaris score changes physicians' treatment decisions.
Industry observers have estimated that in order to garner Medicare coverage, Myriad will need to show that when doctors used Prolaris, they changed at least 20 percent of treatment decisions based on test results. "The data exceeded the endpoints for the study, and demonstrate physicians' willingness to modify their treatment decisions based upon the PROLARIS score," Mark Capone, president of Myriad Genetics Laboratories, said during the call, in presenting interim data from PROCEED.
He highlighted that doctors changed their treatment decisions 65 percent of the time when using Prolaris. Of these physicians, 39 percent of the time they administered a lower level intervention and in 26 percent of the cases "they increased their medical management," Capone said. Additionally, 89 percent of urologists surveyed by Myriad indicated that the Prolaris score had a "moderate to very high" impact on their treatment decisions.
"We continue to believe that we are on track to obtain Medicare reimbursement in the first half of calendar year 2014," Capone said. Although Medicare reimbursement will boost adoption of the test, the company does not expect that Prolaris will significantly contribute to revenues for the current fiscal year.
Myriad said it is in the process of submitting the final clinical utility package for Prolaris to Medicare.