Teaming Up for a Companion Diagnostic

Abbott Molecular of Des Plaines, IL, and biomedical giant Johnson & Johnson will partner on a diagnostic test that identifies chromosome 17p deletions in patients with chronic lymphocytic leukemia (CLL).

Patients with CLL who harbor this deletion respond poorly to chemotherapy. Clinical studies have suggested that patients with various leukemias may respond to Johnson & Johnson's experimental drug ibrutinib, an inhibitor for Bruton tyrosine kinase. Ibrutinib is being developed collaboratively by Johnson & Johnson subsidiary Janssen Biotech of Horsham, PA, and the drug's initial creator, Pharmacyclics in Sunnyvale, CA.

Johnson & Johnson has its own diagnostic development and manufacturing capabilities. However, Janssen's head of companion diagnostics, Ron Mazumder, PhD, says it makes sense to partner with Abbott, because that company's assay for detecting 17p deletions—the Vysis fluorescence in situ hybridization (FISH) test—has already been approved by the U.S. Food and Drug Administration (FDA).

Janssen recently received the FDA's “breakthrough therapy” designation for ibrutinib, meaning that the drug will receive special attention from the FDA as clinical trials are planned and proceed. “We would like to expedite availability of ibrutinib and the diagnostic to patients as soon as possible, and Abbott having a 17p kit on the market will certainly facilitate that,” Mazumder says.

The collaboration reflects a number of recent efforts in which drug and diagnostics companies partner to select patient subgroups for targeted therapy.

Sheila Walcoff, JD, founding principal of Goldbug Strategies in Rockville, MD, comments that the FDA is expected to soon release its highly anticipated final guidance on in vitro companion diagnostics, which will recommend that drug labels for targeted therapies refer to an approved test to identify likely responders. She notes that many drug companies don't develop these tests on their own, however, given the extra expense and resources required.

The test will be used to identify patients with CLL in an ongoing phase II clinical trial who are unlikely to respond to chemotherapy and may then be put on Ibrutinib as an alternative. If the drug is approved, the label will refer to Abbott's FISH test as the approved diagnostic, says Pharmacyclics spokesperson Naomi Cretcher.