MADRID — Analysis of biosimilars has focused mainly on switching from a biologic to a biosimilar; now researchers are looking at patients who switch back. According to a new study, 2938 people with rheumatic disease in Sweden switched from etanercept to the first biosimilar on the market, but 333 patients, or 11%, switched back.
The impetus for this study was to determine real-world trends in biologic and biosimilar use over time, said investigator Rieke Alten, MD, PhD, from University Medicine Berlin. “This is the first time we have data on this,” she told Medscape Medical News.
The patients switched back to etanercept after a median of 55 days, but the reasons are not clear. It could be related to patient concerns or clinical issues, said Lara Lucchese, senior consultant at QuintilesIMS in London, who is also one of the study investigators.
In general, people return to a biologic “because they are not as happy as they expected to be with the new treatment,” Dr Alten said here at the European League Against Rheumatism Congress 2017.
People return to a biologic because they are not as happy as they expected to be with the new treatment.
Before April 2016, when the etanercept biosimilar (Benepali, Biogen) was approved in Sweden, etanercept (Enbrel, Pfizer) accounted for 40% of the market share for rheumatic diseases.
After approval, the number of prescriptions for the etanercept biosimilar steadily increased, and there was “a pretty steep erosion” in the number of etanercept prescriptions. As of March 2017, use was approximately equal, with each agent accounting for 22% of the market, Lucchese reported.
More than half the biosimilar prescriptions — 55% — were preceded by a prescription for etanercept, 4% were preceded by a prescription for adalimumab, and 7% were preceded by a prescription for a different biologic, according to data from the Swedish Prescription Registry. The other 34% of biosimilar prescriptions went to treatment-naïve patients.
During the 1-year study period, 5387 patients filled a prescription for the biosimilar.
Table. Switches From Etanercept Biosimilar to the Originator
| Previous Therapy | Biosimilar Prescriptions | Switch | |
|---|---|---|---|
| n | n | % | |
| None | 1845 | 145 | 8 |
| Any biologic, including etanercept | 3542 | 482 | 14 |
| Any agent other than etanercept | 604 | 83 | 14 |
The “etanercept biosimilar reached half the etanercept market share in less than a year, which is remarkable, considering the noncompulsory nature of biosimilar prescription in Sweden, as opposed to other European countries, like Denmark,” said Filipe Araújo, MD, from the SCML Hospital Ortopédico de Sant’Ana in Lisbon, Portugal, who was asked to comment on the study.
“The number of patients switching back to the originator in an early stage of biosimilar treatment must be interpreted with caution,” Dr Araújo told Medscape Medical News. The finding “suggests the influence of factors other than efficacy or safety, and might be related to patient and physician beliefs and expectations.”
Tips for Counseling Patients About Switches
Often, patients can become confused when a rheumatologist switches therapy from a biologic agent to a biosimilar, Lucchese explained.
In both Sweden and the United Kingdom, the main driver for a switch is economic, and educating patients in advance of a switch can help ease the transition, she pointed out.
Physicians should proceed with caution when advising patients about a switch, Dr Alten advised, because “every little word counts” when you’re talking to patients.
“If I say it’s a wonderful drug that will cure your rheumatoid disease, and you believe me because I’m a very convincing doctor and I look deep into your eyes, the response will be about 30% to 40%.” However, she explained, “if I switch a patient to a biosimilar drug, and tell him or her that I have to give you the cheaper drug now because the GDP is so low in our country, and I’m sorry, then you have the so-called nocebo effect. You have already introduced a negative impact on the efficacy of the treatment.”
Busy clinicians can use educational materials, such as leaflets and online videos, to help explain a switch between a biologic and a biosimilar. The National Rheumatoid Arthritis Society in the United Kingdom provides educational materials to help patients who might otherwise just receive a notice announcing the switch. And the European Medicines Agency provides an information guide to help physicians optimize switches from biologics to biosimilars.
Going forward, “there are a lot of studies we have in mind,” Lucchese reported. “Now that we have more data, we can do a persistence study. We can see, overall, how long the patient is persistent on the product.”
The next step in the research could be to interview patients to gather qualitative information to determine why they switch back from a biosimilar, Dr Alten said.
This study was sponsored by Pfizer. Dr Alten and Ms Lucchese report receiving grant and/or research support from Pfizer. Dr Araújo reports receiving fees from Biogen and, previously, honoraria from Pfizer.
European League Against Rheumatism (EULAR) Congress 2017: Abstract SAT0161. Presented June 17, 2017.
Follow Medscape Rheumatology on Twitter @MedscapeRheum and Damian McNamara @MedReporter
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