Immunotherapy competitors collaborate on 'Blueprint' for diagnostic

Merck & Co has said a project comparing several new diagnostic tests for the immune biomarker PD-L1 in non-small cell lung cancer (NSCLC) produce similar results - a finding which could be helpful in development of future therapies.

The company said trials demonstrate PD-L1 testing could be a useful tool to help identify patients more likely to respond to treatment with an anti-PD1 drug, or an anti-PD-L1 therapy.

The two marketed anti-PD1 drugs from Merck and Bristol-Myers Squibb, Keytruda (pembrolizumab) and Opdivo (nivolumab) are not linked to a biomarker or companion diagnostic.

But the four pharma companies developing similar therapies, BMS, Merck, Genentech and AstraZeneca, were concerned that diagnostic tests need to be comparable should future drugs be linked to expression of PD-L1. Genentech is developing atezolizumab and AZ is developing durvalumab in cancer immunotherapy.

Phase 1 of the Blueprint Project has confirmed there is a high concordance for the two approved PD-L1 diagnostics in NSCLC, including the one used in conjunction with Keytruda, the PD-L1 IHC 22C3 pharmDx assay developed in partnership with Dako North America, part of Agilent Technologies.

Keytruda and Bristol-Myers Squibb's rival, Opdivo (nivolumab) have caused a revolution in oncology as they stimulate a patient's immune system to attack the cancer.

In March 2015, the AACR in partnership with the U.S. Food and Drug Administration and the American Society of Clinical Oncology held a one-day workshop to examine whether multiple companion diagnostics intended for the same class of therapeutics could be harmonised.

During the workshop, the group of four companies and two diagnostic companies released a blueprint proposal to analytically compare and characterise each of their IHC-based PD-1/PD-L1 companion diagnostics for non-small cell lung cancer in the pre-approval stage.

The thought was that, upon approval of these tests, the information generated by this project could lay the groundwork for additional studies that will help inform patients, physicians, pathologists, and others on how best to use the test results to determine treatment decisions.

Results from the Blueprint Project were presented at the American Association for Cancer Research 2016 Annual Meeting.

They are being trialled in a range of cancers and in combination with other drugs. DrugAnalyst research forecasts Keytruda will generate sales of more than $4.7 billion in 2020, and forecasts Opdivo will generate $9 billion in 2020.

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