Companion Diagnostics Information Not Easily Obtained

Charles Bankhead

June 2013, Vol 4, No 5 - Personalized Medicine

San Diego, CA—Getting technical information about companion diagnostic tests required to make formulary decisions about oncology drugs may not be easy, according to a small telephone survey conducted by Aashish Surti, PharmD can­didate, and Iris Tam, PharmD, Di­rector, Managed Care Med­i­­cal Com­mu­n­i­­cations, Genentech. They reported their survey results in a poster presented at the 2013 Academy of Man­aged Care Pharmacy (AMCP) meeting.

Only 1 of 20 phone calls to test and drug manufacturers resulted in the direct provision of the package insert for a diagnostic test. The remaining calls resulted in referrals to different departments, websites, or companies. When information was provided, it usually came in the form of generic product information or “uninformative” medical letters about the tests.

“This study suggests that gaps exist in obtaining diagnostic test information—including information about a test’s analytical validity, clinical validity, and clinical utility—from diagnostic test and drug manufacturers,” the investigators concluded.

Obtaining information about companion diagnostics may be important to evaluate cancer drugs that are used in conjunction with companion diagnostic tests associated with specific biomarkers to make appropriate formulary decisions.

The US Food and Drug Admini­s­tration (FDA) has released a draft guidance related to drug and device manufacturers’ responses to unsolicited requests about medical information for new products. In response to the FDA’s action, most drug manufacturers have developed standard policies and procedures for responding to unsolicited requests for information.

Less is known about how manufacturers of diagnostic tests respond to requests for information about companion tests required for drugs undergoing formulary review, they said.

Companion Diagnostics for Targeted Oncology Therapies
The role of companion diagnostic tests has expanded with the growing number of targeted therapies, particularly in oncology. Effective and cost-effective use of agents requires selection of patients most likely to benefit from the drugs.

The growing number of biomarkers identified in association with certain tumor types has fueled development of tests to identify subpopulations of patients with targeted genetic mutations.

This study focused on several FDA-approved, commercially available companion diagnostic tests for oncol­ogy biomarkers, including tests for ALK, V600E, EGFR, HER2, and KRAS gene mutations.

The investigators made telephone calls to request information about diagnostic tests from manufacturers of the diagnostic tests and from the associated drug companies.

Of the calls that were made to the test manufacturers, only 1 response led directly to the requested information.

The AMCP recently released the Format for Formulary Submissions, Version 3.1, which includes an addendum specific to companion diagnostic tests. Whether that development will influence manufacturers’ responses to requests for information about diagnostic tests remains to be seen.