A multi centre chart review examining data on patients treated with biologic therapies for psoriasis has found that while treatment adherence dropped off over the five years patients were tracked, adherence was significantly higher for ustekinumab compared to the other three therapies evaluated.
“It is not uncommon for patients to switch biologics,” said the paper’s senior author, Dr. Jensen Yeung, in an interview with The Chronicle of Skin & Allergy.
However, it is becoming more difficult to get a patient onto a biologic or to switch them to a
different biologic, he noted.
Cost of switching therapies is high
“We have t o re-start the process again, and the paperwork, so ideally we want to use an agent that we are quite confident the patient will maintain on for a long period of time,” said Dr. Yeung, a dermatologist at Sunnybrook Health Sciences Centre in Toronto and the medical director of the Phototherapy Education and Research Centre at Women’s College Hospital at the University of Toronto. He is also an investigator with Probity Medical Research in Waterloo, Ont.
The decision to examine drug survival was made for two major reasons, said Dr. Yeung.
“Drug survival of biologics in psoriasis is not something we have a lot of data on. There have only been a handful of publications looking at drug survival [in real world practice]. We had a lot of data [on the patients from the participating centres], so we thought we would look at that to see how many patients remain on their drug after year one, two, three, four and five.”
Drug survival is defined as the time from initiation to discontinuation (stop/switch) of biologic therapy at a particular time point.
Drug survival is a very good shorthand measure to evaluate how well a drug works overall, said Dr. Yeung. “Survival encompasses different factors. One is efficacy, one is patient
preference, and one is safety.”
Nearly 400 patient records reviewed
Because of the challenges associated with having to switch patients to new biologics, and the limited data on biologic drug survival in real-world psoriasis treatment scenarios, the authors conducted a multicentre chart review using patient data from Sept. 2005 to Sept. 2014, with the goal of identifying which biologics patients were more likely to continue to use.
Records from 398 patients, totalling 545 treatment series, were analyzed. Investigators used Kaplan-Meier plot analysis to determine five-year drug survival rates, and a log-rank test to compare rates between four biologic drugs: etanercept, adalimumab, infliximab, and ustekinumab.
The observed 1, 2, 3, 4, and 5-year survival rates for the four drugs were: 0.826, 0.687, 0.563, 0.475, and 0.420 with etanercept; 0.804, 0.648, 0.553, 0.508, and 0.508 with adalimumab; 0.838, 0.664, 0.554, 0.485, and 0.382 with infliximab; and 0.914, 0.856, 0.800, 0.755, and 0.755 with ustekinumab.
“You can see from the data that a lot of patients switch biologics within the first five years,” said Dr. Yeung. “From this study we found that ustekinumab had the best drug survival. And when we compared the other anti-TNF [drugs], there is no difference amongst the three of them.”
While one could speculate about the cause of the statistically significant difference in drug survival between ustekinumab and the other three biologics—efficacy, safety, or the number of injections needed per year and the associated pain and risk of injection-site reactions—Dr. Yeung emphasizes that this consideration is outside the scope of this study.
Latest of four papers
This study was the most recent of four papers based on the data emerging from the review.
Because the chart review is a time-consuming process, “we wanted to capture everything when the charts were reviewed,” said Dr. Yeung.
“We looked at efficacy of different biologics at week 12. We examined safety data—how many patients actually withdrew treatment due to an adverse event,” said Dr. Yeung.
“We also reviewed patients who had failed at least one biologic before—what were their chances of responding to a subsequent biologic, whether it is within the same class or a different class.”
“And this is the last one, to look at drug survival,” he said.
Dr. Yeung said he and his team plan to look at similar data on newer biologic drugs for psoriasis next, including secukinumab, ixekizumab and apremilast.