Psoriasis, with its patches of itchy, flaky skin, is often nothing more than a benign cosmetic problem. Yet, for many people, it’s as disabling and threatening as rheumatoid arthritis or cancer.
These patients often don’t tolerate existing medicines, or see them lose their power over time. Pharmaceutical companies, including Indianapolis-based Eli Lilly and Co., have a new understanding of the biology behind the disease and are developing a new class of drug candidates that may be faster and more effective for the more serious forms of psoriasis.
The front runner, Novartis AG, said Thursday that its experimental treatment met the main goals of a late-stage study.
Psoriasis is linked to higher rates of heart disease and diabetes, and a third of patients also develop a form of arthritis, which causes pain and swelling in and around the joints, said Kristian Reich, a dermatologist in Hamburg who also teaches at the University of Goettingen.
“This is a really serious inflammatory illness, like rheumatoid arthritis, except that it doesn’t affect the joints, it affects the skin,” said Reich, who has tested the Novartis drug and two others in clinical trials.
It’s impossible to gauge the full toll of psoriasis on people’s lives. In addition to the physical pain and danger of complications are the psychological wounds.
“These people don’t get the jobs they should be getting,” Reich said. “They don’t marry the partners they should be marrying.”
About 125 million people worldwide have the skin condition, including 7.5 million Americans, according to the National Psoriasis Foundation. About 20 percent to 30 percent of them have a moderate to serious form of the disease, of which half are taking some kind of medicine, said John Hohneker, who heads drug development for autoimmune diseases at Basel, Switzerland-based Novartis.
“We know that 40 to 50 percent are dissatisfied with their current therapy,” Hohneker said.
Novartis’s therapy, secukinumab, worked “significantly” better than Amgen Inc.’s Enbrel, the $3.7 billion-a-year drug that is considered the standard of care, in clearing the skin in a late-stage study, the company said in a prepared statement. The research is being presented at the European Academy of Dermatology and Venereology meeting in Istanbul, which began Oct. 2.
Lilly and a partnership of Amgen and AstraZeneca Plc are also working on new medicines. Lilly said it expects late-stage results next year.
Brodalumab, the drug from Thousand Oaks, Calif.-based Amgen and AstraZeneca of London, is also in late-stage testing. At the conference, the companies will present results from the second of three phases of human testing usually required by regulators.
Older therapies block a chemical called TNF, which is produced by the immune system and causes inflammation in the body. TNF blockers are used against a variety of autoimmune diseases, including rheumatoid arthritis.
The new drugs block IL-17, a protein involved in sending signals in the immune system. Psoriasis occurs when the immune system over-reacts to cuts or scrapes, leading to an abnormally rapid buildup of skin cells. Scientists found the points of attack through better understanding of the protein.
Because the new psoriasis drugs target IL-17, they may have fewer side effects than older medicines, start working faster and require fewer injections, according to Andrea Chiricozzi, a dermatologist at the University of Rome who has studied the biology of the disease.
“For these agents, the efficacy is very good, and there are no major concerns about safety,” Chiricozzi said. Side effects in clinical trials have included common colds, upper respiratory tract infections and injection-site reactions.
People who have psoriasis usually try a range of both over- the-counter and prescription creams before starting to take methotrexate, a cheap generic drug, treatments that may not be sufficient for patients with a more severe form of the disease.
Then they move to injectable therapies such as Enbrel from Amgen, or Humira from North Chicago, Illinois-based AbbVie Inc. Both Enbrel and Humira are TNF blockers and are used to treat rheumatoid arthritis, which like psoriasis is an autoimmune disease. Patients may also take Johnson & Johnson’s Stelara, a drug approved to treat psoriasis. Stelara targets IL-12 and IL-23, two other proteins that play a role in the immune system’s responses.
The TNF blockers don’t help every patient and may become less effective over time, said Lawrence Green, a dermatologist in the Washington, D.C., area and chairman of the National Psoriasis Foundation’s research committee.
If drugmakers succeed in winning approval for the new medicines, the products have the potential to expand the psoriasis market from the $5 billion now spent on expensive biological therapies to $8 billion by 2017, according to Andrew Baum, a pharmaceutical-industry analyst at Citigroup Inc.
The drugs in development are better at clearing the skin than older therapies, according to Citi’s Baum. In mid-stage clinical trials, the experimental medicines were deemed effective in about 80 percent of patients, compared with 49 percent for Enbrel and 75 percent for Humira.
“Patients want to have normal lives,” Novartis’s Hohneker said.