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pharmalive.com/magazines/randd/view.cfm?articleID=9757Executives with the immunology therapeutic area team at Centocor Research and Development, a unit of Johnson & Johnson, spoke with R&D Directions about the promising advances and continued roadblocks in targeting autoimmune diseases, a treatment class that has grown rapidly in recent years.
The Johnson & Johnson Family of Pharmaceutical Companies has traditionally been active in the immunology field, paced by popular tumor necrosis factor, or TNF, inhibitor Remicade and other approved therapies Simponi and Stelara.
Sue Dillon, Ph.D., global therapeutic head, immunology, J&J Pharmaceuticals R&D, and Miguel Barbosa, Ph.D., head, immunology research and external innovation, J&J Pharmaceuticals R&D, discussed the clinical progress in expanding the reach of these products in other autoimmune indications, and also touched on novel projects in J&J’s immunology pipeline.
R&D Directions: Major autoimmune diseases such as Crohn’s disease, psoriasis, and lupus still present significant unmet need. Have strong advances in understanding the molecular basis of these conditions boosted hopes for more effective treatments?
Dr. Dillon: There have been some important discoveries over the last couple years in each of those disease areas. The discoveries result in part from the success of some of the new therapeutics that are in development, which are directed against new targets. But also from translational work, working with cells and tissues from patients with these diseases, and looking at which genes and proteins are expressed in the diseases. And then also at the genetic level, looking at changes in the genes of people with these diseases, and starting to understand some of the so-called polymorphisms, which are just changes in the DNA sequences of specific genes.
For autoimmune diseases like psoriasis and Crohn’s, there’s been an increasing focus on different T-cell subsets that are involved. In particular, a subset of T-cells called Th17 cells are increasingly believed to be very important in psoriasis and inflammatory bowel diseases – both Crohn’s and ulcerative colitis. The cytokine that helps sustain these cells, called IL-17, is found in the tissue, whether it’s in psoriasis, skin lesions, the inflamed intestine, or even in rheumatoid arthritis, in the inflamed synovium.
More recently there have been some very early studies with antibodies against IL-17 that have started to show some efficacy, particularly in RA. That’s getting a lot of attention. Another is the cytokines IL-12 and IL-23. Our own drug Stelara blocks both of those cytokines.
Through the clinical study of psoriasis, we’ve been able to confirm the pathogenic importance of IL-12 and IL-23 in psoriasis. In addition, there’s a lot of data that’s pointing to those cytokines being important in inflammatory bowel diseases as well. Again, this is discovered through translational studies and genetic studies in humans.
Interestingly, IL-23 is one of the cytokines that’s very important in driving the differentiation of the Th17 cells. There’s a molecular pathway that connects IL-23 and IL-17. That whole pathway seems to be really important in all of the autoimmune diseases that specifically have been treated with anti-TNFs. That’s very exciting, because it provides a novel mechanism for people who either don’t respond to TNFs or lose their response to TNFs.
In the case with lupus, probably the most exciting thing that’s happened there is the activity that’s been shown by an antibody by [Human Genome Sciences Inc.] called belimumab, or Benlysta. It recognizes a T-cell cytokine called B-lymphocyte stimulator. That cytokine drives B-cells to become mature cells called plasma cells that are responsible for actually making the antibodies and also making pathogenic antibodies, or autoantibodies, which recognizes the body’s own tissue.
As with so many of these other antibody treatments, they basically establish in humans that at least one pathogenic mechanism now can firmly be said to be rooted in autoantibody production by B-cells. That will then also pave the way for other approaches for lupus.
R&D Directions: What key challenges remain in autoimmune research?
Dr. Dillon: The challenges in these diseases are huge, even though there have been tremendous advances. One challenge is achieving remissions, as opposed to simply responses, and having those remissions be durable. Balancing that with better safety profiles is also important. I think some of these new therapies have the potential to make more progress toward that than we’ve seen in the past.
The other really big challenge is that for all of these diseases, the patient populations are pretty heterogeneous. There are definitely people who are on different ends of the spectrum with respect to severity, but also probably have different pathways that are responsible for mediating the disease. We’ve been working hard on trying to better understand the patient subsets and ultimately get to the point where we might be able to actually predict which patient will respond to which drug. That’s a really big emerging science within immunology.
Finally, all the progress has really been made to date with biologics. Clearly the world is looking for oral drugs, small-molecule drugs that will have equal efficacy and hopefully equal or better safety. There is some progress being made there with the kinase inhibitors that are in Phase III and other ones that are earlier in development. Basically, these oral drugs generally address targets that, unlike the antibodies, are inside the cell, and are the signaling of the cytokines that are blocked by antibodies. They are sort of related in mechanism, although they tend to be much less selective than the antibody approaches.
R&D Directions: How is the use of biomarkers, informatics, and other translational tools aiding research efforts in the immunology field?
Dr. Dillon: There is active work going on in RA and in inflammatory bowel diseases in Crohn’s to identify biomarkers that might predict the likelihood that someone will response to, for example, TNFs. We’ve published a paper where we’ve looked at the gene expression profiles within the messenger RNA profiles in patients that are being treated with infliximab (Remicade) that have ulcerative colitis. We identified a so-called gene expression signature. That’s the foundation of where we’re trying to go and then building upon that in order to better understand the disease and better understand how to use the molecules that we’re developing.
Dr. Barbosa: Working with academic research laboratories, we are building internally what’s referred to as disease-metric databases that have a lot of the information related to disease phenotypes and mechanisms. They have information related to molecular targets and individual biochemical entities and proteins, as well as information that’s available from drug discovery efforts that we have ongoing throughout the organization in using advanced informatics tools that allow us to extract correlations across those areas – from the target to the pathway to the cell type to the organ, all the way to the disease that we see in patients.
Exploring that information develops a number of testable hypothesis that the research scientists are able to study in the labs, both internally within the organization as well as through the collaborations we have. It is the process of target validation that builds the dataset that determine decisions whether to embark on a full fledged R&D effort or not.
A key part of building these disease-centric databases is the analytical tools that one applies to that. We’re active in exploring this new area referred to as networked pharmacology, which brings in both the biological data as well as the chemistry data to define approaches for novel therapeutics. That is really at the foundation of our research strategy – bringing the translational data in different systems to disease samples through various advanced informatics analysis.
R&D Directions: What are some novel candidates in J&J’s immunology pipeline that are particularly promising?
Dr. Dillon: One very exciting program that we have is a human antibody directed against the IL-6 ligand. It’s called CNTO 136. This program is in Phase II for rheumatoid arthritis and is about to enter Phase IIa for lupus nephritis. IL-6 is a cytokine with many different activities. It’s one the cytokines that’s responsible for driving B-cells to make antibodies. It has a role in driving the production of Th17 cells. IL-6 also has a role in cartilage and bone turnover. We think that by blocking IL-6, we can hit several of these different pathways at the same time.
We think [CNTO 136] will be an important novel mechanism in RA, particularly for patients who have already experienced TNFs, or they have lost response or did not tolerate being on an anti-TNF therapy.
Another key target is CCL2. The antibody we have directed against CCL2 is called CNTO 888. CCL2 is responsible for the migration of macrophages into sites of inflammation. It’s also responsible for the migration of a cell type called fibrocytes into sites of inflammation. We think CCL2 has an important role in driving fibrosis within the tissues through the recruitment of these cell types.
We’re studying CNTO 888 in idiopathic pulmonary fibrosis, which is a disease where there is progressive fibrosis in the lungs. The trigger for the disease is really not understood, but there’s a very high morbidity and mortality and really no effective treatments out there. We’re in a Phase II proof-of-concept trial with CNTO 888 in that indication. On the small-molecule side, one of the areas that we’re very active in are oral small molecules directed against a class of histamine receptors called histamine type 4 receptors. We have two different molecules that are in development that are directed against the histamine H4 receptor. The receptor was actually discovered by scientists out in our La Jolla, [Calif.,] research group. They were pioneers in cloning and expressing this target and understanding the biology – and now we’re one of the leading labs in the world with molecules that are being tested in various indications. We’re looking at rheumatoid arthritis and asthma with these molecules.
The other exciting program that we have on the small molecule front comes through an acquisition that we recently made of a company called RespiVert [Ltd.] These are molecules that are delivered by the inhaled route. They are inhibitors of intracellular kinases that are important in driving inflammation and in particular driving inflammatory pathways that seem to be insensitive to steroids. That program is in very early clinical development.
R&D Directions: How are clinical pursuits progressing to expand Simponi and Stelara?
Dr. Dillon: Both of those drugs were approved in 2009, initially in the U.S. and Europe, and they have continued to receive approvals around the world, Simponi for rheumatoid arthritis, psoriatic arthritis, and ankylosing spondylitis, and Stelara for chronic psoriasis. Both of them are under study in various additional indications.
With Simponi, we’re planning to file a supplementary [biologics license application] for structural damage claims in rheumatoid arthritis and psoriatic arthritis. In addition, we’re studying a novel formulation for rheumatoid arthritis using an IV. The original approval is for once-monthly subcutaneous administration. The IV program is interesting because it would be the first ant-TNF antibody which has both routes of administration. You could manage the disease through either subcutaneous or intravenous delivery in the same patient – depending on various factors, including the severity of the disease – without having to switch between different TNFs. We’re also in Phase III with Simponi for ulcerative colitis.
We have a proof-of-concept study ongoing in a disease called sarcoidosis, where we’re studying Simponi and Stelara in the same program. The reason that we’re studying sarcoidosis is based on a lot of the very interesting translational data that was developed about the potential role of TNF and IL-12 and IL-23, which are the targets for Stelara in that disease.
With Stelara, we’re studying psoriatic arthritis in Phase III. We’re also studying the drug in Crohn’s disease, again driven by, No. 1, a lot of the biology that’s pointing to IL-12 and IL-23 in inflammatory bowel disease, and also because of the need to have an option for people who do not respond or lose their response to the anti-TNF, which is a very severe unmet medical need in inflammatory bowel disease.
We’ve invested heavily over the last several years in three areas. First, new drugs for the diseases that we already have approvals. Secondly, we’re looking to move into diseases that have not been adequately addressed yet or addressed at all through biologics therapy or any type of therapy. On that list are diseases like lupus, idiopathic pulmonary fibrosis, and sarcoidosis.
The third major thrust for us is to establish a franchise in pulmonary diseases, where we’re new to the game. We don’t have products, but through the translational efforts and Miguel’s group, the acquisitions, the collaborations, and moving the pipeline forward, we are beginning to see emerging a very nice portfolio in the pulmonary area.
R&D Directions: Your group focuses on external innovation for immunology as well. What are some examples of that involving J&J, and how important are collaborations in this area?
Dr. Barbosa: We view external innovation as important to all of our efforts across R&D. Through this effort, we’ve established several collaborations. As an example, a key collaboration that was just announced was with Orexo [AB], a European biotech company. They are leading experts in the biochemistry and pharmacology of the arachidonic acid pathway. The driver for this was our strategic pursuit in building a franchise in pulmonary through internal means and external innovation and accepting a complementary external expertise.
Another collaboration example is in the field of novel biologic proteins, where [in 2008] we established a partnership with Molecular Partners, a European biotech that has a key biologic platform referred to as DARPin. Through this collaboration, we are moving forward in R&D a novel biologic agent for our respiratory portfolio.
We also continue to expand our network of collaborations with academic institutions. One of our significant collaborations is with the University of Michigan, which involves multiple projects. Some projects are focused in understanding the underlying mechanisms leading to some of the pulmonary pathologies. In other cases, we are looking at actual target-specific projects, where we are in collaboration with academic labs looking at modulating a specific target through the process of validation.
We also have a partnership with a leading biotech company in China called Hutchison MediPharma [Ltd.] that allows us access some external innovation and do so in a country where we have a very long-term strategic interest. We get to interact with the talent present there, as well as conduct discovery research in that partnership.
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