Abbott said today that it has signed a pact with GlaxoSmithKline to develop a PCR-based molecular diagnostic test for a specific biomarker to aid in selecting patients who may benefit from an immunotherapy under development at GSK.
The agreement builds on a partnership between the companies announced last year to develop a PCR test for the same protein biomarker — MAGE-A3 — to screen for non-small-cell lung cancer patients eligible to receive GSK's developmental NSCLC therapy, called MAGE-A3 Antigen-Specific Cancer Immunotherapeutic, or MAGE-A3 ASCI.
Under both agreements, Abbott and GSK are developing a PCR test for use on Abbott's m2000 automated real-time PCR system to detect the expression of MAGE-A3, a tumor-specific antigen that is expressed in skin cancer, NSCLC, and a variety of other cancers, but not in normal cells, Abbott said.
GSK is currently evaluating MAGE-A3 ASCI as an adjuvant treatment in melanoma biopsy specimens in DERMA, a large Phase III clinical study of patients with stage 3B or 3C melanoma that has spread to the lymph node, and who have had an operation to remove their tumor.
To be eligible to receive GSK's MAGE-A3 ASCI, patients must have MAGE-A3-epxressing melanoma tumors.
Under the first agreement between the companies, announced in July, Abbott was to develop a PCR-based test using the m2000 system to screen for NSCLC tumors that express MAGE-A3 to determine whether patients would be eligible to receive the developmental drug in Phase III trials for that cancer.
A spokesperson for Abbott told PCR Insider in an e-mail this week that Abbott and GSK are "making progress toward the validation of the [NSCLC] assay … working with GSK on the Phase III clinical trial … [and] are on schedule for a late 2012 launch pending clinical trial results."
Both the NSCLC and skin cancer tests are intended to be companion diagnostic assays, "thus the drug and diagnostic are reviewed by the FDA simultaneously, though separate branches of the FDA facilitate the approval process," the spokesperson said. "Upon approval, in both lung and melanoma, the test will be required in order to prescribe the therapy; therefore FDA approval of the test is required to prescribe the therapy."
Currently, there are no nucleic acid-based tests approved by the US Food and Drug Administration for use in identifying patients who may benefit from targeted skin cancer therapies, Abbott said.
Abbott and GSK said they will seek regulatory approval for the new test in several markets, including the US and Europe.
The Abbott m2000 is an automated system for DNA and RNA testing that comprises the m2000sp module for automated sample extraction preparation and the m2000rt instrument for real-time PCR detection and analysis.
Outside the US, Abbott offers an extensive menu of infectious disease tests on the system, including for HIV-1 viral load, hepatitis B and C viral load, chlamydia, chlamydia/gonorrhea combination, hepatitis C virus genotyping, cytomegalovirus, Epstein-Barr virus, and human papillomavirus.
In December, Abbott launched the first oncology assay for the m2000 system: the Abbott RealTime mS9 colorectal cancer test, which detects the methylated form of Septin 9, a gene linked to colorectal cancer, in blood specimens.
The test is available in Europe and Asia, but not the US, and was developed in partnership with Epigenomics, which granted Abbott non-exclusive worldwide rights to the Septin 9 biomarker in late 2007.
Only the RealTime HIV-1 and RealTime Chlamydia/gonorrhea combination test are currently available on the m2000 system in the US.
Abbott's spokesperson also said that the FDA is currently reviewing m2000-based tests for hepatitis B viral load and chlamydia/gonorrhea for US regulatory approval; and that Abbott expects to submit a test for hepatitis C viral load for review shortly.