Johnson & Johnson is not one to avoid pharmacogenomics for fear that it will hasten the downfall of the blockbuster model. Rather, the drug maker has been collecting DNA samples routinely in clinical trials for several years and using a variety of genomic strategies to enhance the safety and efficacy of its drug candidates.
At a conference last month hosted by the Harvard-Partners Center for Genetics and Genomics in Boston, Garry Neil, vice president of J&J’s office of science and technology, outlined some of the ways the company uses PGx strategies to advance personalized medicine.
“I want to disabuse everyone of the notion that the pharmaceutical industry, and J&J in particular, is resistant to the advancement of personalized medicine and pharmacogenomics because it’s opposed to the blockbuster model,” Neil said during his talk. “We realize that the future of personalized medicine is now, and we really need to embrace this if we’re going to be successful.”
J&J's interest in PGx coincides with other drug makers' use of such technologies, including Lilly, Novartis, and Pfizer [see PGx Reporter 11-28, 2007].
The “most important factor the pharma industry has to face involves the simple fact that drugs don’t work, at least not all of the time, and that drugs are toxic, at least some of the time in some people,” Neil said. “So we need to do better.”
Neil said that as the industry “move[s] toward these new models of reimbursement and requirements for demonstrating safety, efficacy, and cost-effectiveness of medicines, our goal is to identify patients who will benefit, to exclude people who will be harmed, and to ensure optimal dosing and optimal compliance.”
According to Neil, J&J uses PGx strategies in three principal ways: to strengthen its pharmacokinetics R&D programs, to improve drug safety and efficacy, and to select trial patients most likely to respond to its products. More generally, the company uses PGx tools to design clinical trials for regulatory submissions, product differentiation, companion diagnostic development, and portfolio decision making, Neil added.
Another way J&J has been using PGx tools is by collecting DNA samples for its clinical trials. Today, the company has access to approximately 7,000 samples related to schizophrenia and around 3,000 samples associated with Alzheimer’s disease that it can tap to help it look for drug targets for these indications. “This has enabled us to conduct large-scale analyses in these diseases,” Neil said.
Additionally, J&J and Illumina have recently developed a DNA chip covering 1,000 genes and 30,000 SNPs associated with various psychiatric indications. The drug maker has already used the chip to genotype about 4,000 patient samples, “and the data look very promising in yielding new insights about [disease] mechanisms and about treatment responders,” Neil said.
J&J also routinely uses PGx technologies in ADME studies to better understand a drug’s pharmacokinetic profile for poor or extensive metabolizers.
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“We realize that the future of personalized medicine is now and we really need to embrace this if we’re going to be successful.” |
“That has been extremely useful for us to understand why patients aren’t responding in Phase II trials, to make adjustments in Phase III, or to even have discussions with regulatory agencies,” Neil said.
Other PGx uses include an assay made by J&J subsidiary Veridex that identifies the presence of rare circulating tumor cells, which signal metastasis. The assay, which runs on Veridex’s CellSearch system, has been approved by the US Food and Drug Administration.
“We’re now evaluating the utility of this [assay] as a theranostic or valid biomarker for metastatic breast cancer,” Neil said.
J&J is also using PGx strategies to hone the safety of Eprex, an erythropoietin drug it voluntarily removed from the European market in 2002 after a study linked the drug to increased mortality.
“We recently noticed a pretty significant safety issue, pure red blood cell aplasia, in a small minority of patients treated with [Eprex] and we ultimately … withdrew it from the market,” Neil said. “We noticed in some populations that there was a higher incidence [of pure blood cell aplasia] than in others, and investigations … helped us identify a specific HLA genotype that was associated with a much higher risk and suggested a more intensive monitoring strategy for this safety problem.”
If PGx strategies allow J&J to improve the drug’s safety, the company can essentially launch an improved version of the product in Europe and regain some of its market share. In 2001, Eprex and sister drug Procrit, developed by Amgen and sold in the US by J&J, contributed $3.4 billion to J&J’s top line.
Ultimately, PGx strategies have “helped [J&J] to set realistic expectations,” said Neil. “A combination of scientific reasoning, trial and error, and a lot of risk-taking on our part has led to a rapid growth in our understanding of how pharmacogenomics can be best applied to clinical development programs,” he said.
“I think we’re suddenly reaching that inflection point in the discipline of pharmacogenomics where we have accumulated an enormous amount of data and we’re thinking about how we’re going to make sense of that data, and that’s going to lead us to … a growth of knowledge,” Neil said.