By Turna Ray
Announcing its second companion diagnostic deal in less than six months, Pfizer last week announced it will work with Qiagen subsidiary DxS to develop a companion test for a brain tumor treatment.
The drug, an epidermal growth factor receptor-targeting immunotherapeutic in Phase II studies for the treatment of glioblastoma multiforme, was developed by Celldex Therapeutics in collaboration with researchers at Duke University's Brain Tumor Center and MD Anderson Cancer Center. In April 2008, Pfizer licensed exclusive worldwide rights to the investigational drug, called PF-04948568.
The Phase II study underway is looking at how effective PF-04948568 is in terms of survival in newly diagnosed GBM patients whose tumors express EGFR variant III. Between 25 percent and 40 percent of GBM patients express this mutated form of EGFR.
"The Qiagen assay is designed to identify those patients whose tumors express the EGFRvIII mutation, allowing for the possibility of more targeted and personalized treatment," Pfizer said in a statement. The real time-PCR test will be developed and manufactured at Qiagen's Center of Excellence for Companion Diagnostics in Manchester, UK, a facility the company gained through its acquisition of DxS last year. Financial terms of the diagnostic agreement were not disclosed.
Andrew Webb, sales and marketing director for Qiagen's DxS business, told Pharmacogenomics Reporter sister publication GenomeWeb Daily News at the Molecular Medicine Tri-Conference in San Francisco last week that Pfizer holds the intellectual property rights to the EGFR variant III marker, but that DxS has negotiated the right to "operate within the Pfizer license."
He said that Qiagen will commercialize the test while Pfizer will market the compound.
A DxS spokesperson told Pharmacogenomics Reporter this week that if clinical trials are successful in identifying a genetic association between EGFRvIII mutation status and drug efficacy, "regulatory approval for sale of the [test] kit will need to be obtained from the US Food and Drug Administration."
Several early studies have found EGFRvIII mutations may predict response to certain targeted drugs for GBM.
A study by Mellinghoff et al., published in the New England Journal of Medicine in 2005 showed that coexpression of EGFRvIII and PTEN by glioblastoma cells is associated with EGFR kinase inhibitors. Other studies have shown that drugs such as Pfizer's Neratinib, AstraZeneca's Iressa, and Genentech's Tarceva inhibit the growth of cells with EGFRvIII in vitro and tumor growth in vivo.
Pfizer appears to be particularly focused on personalizing its oncology pipeline. Previous to this deal with Qiagen, Pfizer inked a deal in August with Abbott Molecular Diagnostics to develop a genetic test that will determine which non-small cell lung cancer patients should receive Pfizer's investigational drug known as PF-02341066 [see PGx Reporter 09-02-2009].
The drug giant is also working with Genomic Health to identify prognostic markers for renal cancer. The collaboration may eventually expand to identifying genetic markers that predict response to a Pfizer kidney cancer drug [see PGx Reporter 01-27-2010]. In May, Pfizer said it was working with Almac Diagnostics and the PETACC3 Translational Research Working Party to identify molecular subtypes in colorectal cancer.
In June last year, Pfizer invested $6 million in the Canadian research effort POP-CURE to spur the discovery and development of biomarkers to personalize new and existing colorectal cancer drugs in Pfizer's pipeline [see PGx Reporter 07-29-2009].
For its part, Qiagen is also focusing on inking additional Rx/Dx partnerships going forward. Qiagen's purchase of DxS last year helped the instrument and reagent developer enter the personalized medicine space, since DxS had already inked Rx/Dx deals with several pharmaceutical partners, including Amgen, ImClone, Boehringer Ingelheim, and AstraZeneca.
At the time Qiagen acquired DxS, the company said it had more than 15 partnerships with pharmaceutical firms to develop pharmacogenomic or companion diagnostic assays.