Adoption of Companion Diagnostics: What's Holding Companies Back?

Proponents of companion diagnostics say that although these tests are the keystone of personalized medicine, there are many potential roadblocks to their practical implementation.

Although some may say companion diagnostics are key to the field of personalized medicine, their development may be a bit more difficult than anticipated, according to a panel of industry experts from the Tufts Center for the Study of Drug Development.

Companion diagnostics is defined by The Academy of Medical Sciences and the Royal Academy of Engineering as “a device intended to select patients with a previously diagnosed condition or predisposition for eligibility of treatment with a specific medicinal product.” In other words, the tests identify the presence or absence of biomarkers for particular mutations that can occur within the various subsets of a particular disease state.

The Tufts panel members noted that interest in companion diagnostics is high, as drug companies are aware that developing these types of tests in concert with a drug may help the drug’s chances of gaining FDA approval. The link between a diagnostic test and a drug may help the agency predict the health outcome and efficacy of a drug, and often diagnostics tests can even provide clinical information to aid in the development of potential new drug therapies.

But there are some hurdles to their implementation, the panelists pointed out. Regulations for each diagnostic differ drastically, and there is a “lack of precedent for codevelopment elsewhere” in the world. Additionally, problems arise when drug developers partner with outside companies to develop the tests, because the companies may have different business models and use different technologies to produce their products.

There is also some uncertainty surrounding the coverage by payers of diagnostic tests, as well as some doubt as to how cost effective they are. Payers must have a high degree of confidence in the tests before they will cover them, and some diagnostic tests result in false positives. Different labs may render different results as well. As Albert Thigpen, senior vice president of pharmacy operations & industry relations at Catamaran Corporation, pointed out a Specialty Pharmacy Times interview, “There’s not necessarily clear quality standards put in place for the labs that are rendering the tests back for companion diagnostics and there needs to be a leveling of the playing field of reputable labs and companies that can manage the tests appropriately with a high degree of sophistication and quality.”

“Despite these difficulties, interest in developing companion diagnostics remains strong,” said Christopher-Paul Milne, director of research at Tufts Center for the Study of Drug Development. A recent example of this interest lies with Boehringer Ingleheim’s afatinib, an investigational oncology compound with an orphan drug designation for patients with EGFR mutation—positive locally advanced or metastatic non-small cell lung cancer. Qiagen is seeking the FDA's approval for a companion diagnostic to screen patients who may benefit from afatinib. Boehringer Ingleheim is also partnering with Horizon Discovery Ltd to support the identification of predictive biomarkers for its molecular entities.

“Early identification of mutation status facilitates a personalized treatment plan with the goal of improving outcomes and—as many studies show—can help reduce health care costs,” Kevin Lokay, vice president and business unit head of oncology at Boehringer Ingelheim, told Specialty Pharmacy Times. “Our hope is that the entire healthcare community, including payers, will continue to adopt reflex testing as a standard practice—as it will help get the right treatment to the right patient at the right time.”