Safety Concerns Prompt Prescription Changes Among Gastroenterologists

Safety Concerns Prompt Prescription Changes Among Gastroenterologists

A survey of gastroenterologists in the United States shows that data from the VARSITY clinical trial, as well as safety concerns about the experimental treatment Xeljanz, are affecting how some medications are prescribed for the treatment of inflammatory bowel disease (IBD).

The survey was conducted by the analytics company Spherix. In it, around 100 gastroenterologists were asked about their perceptions of brands competing for a share of the IBD market.

The first notable finding from the survey has to do with results from VARSITY, a Phase 3 clinical trial (NCT02497469) that compared two IBD treatments: Entyvio (vedolizumab) and Humira (adalimumab). Entyvio works by preventing inflammatory cells from getting into the intestines; Humira is an anti-TNF therapy, meaning it works by blocking the inflammatory signaling molecule TNF (tumor necrosis factor).

Humira is made by AbbVie, and Entyvio is made by Takeda, which sponsored the VARSITY trial. Results from the trial suggested that Entyvio was better than Humira at managing moderate to severe ulcerative colitis (UC), a type of IBD.

According to a press release from Spherix, in the survey, “the majority of respondents report the VARSITY data will have a strong, positive impact on their UC prescribing of Entyvio.” Furthermore, respondents who were aware of the trial reported being more likely to prescribe Entyvio than Humira and to believe that the former is the more effective treatment, for UC, at least.

For Crohn’s disease — another type of IBD — responses were somewhat more mixed; however, there was still a slight trend toward gastroenterologists being more likely to prescribe Entyvio than Humira.

Additionally, there is evidence from the survey that the results could be extended to other TNF inhibitors: “A sizable percent of respondents agreed that since Entyvio demonstrated superiority over Humira with respect to achievement of clinical remission and mucosal healing, it is likely superior to other TNF inhibitors, including infliximab (brand name Ixifi)”

The survey respondents also reported that Janssen’s Stelara performs better than Entyvio at controlling Crohn’s disease. Stelara works by blocking the action of interleukin (IL)-12 and IL-23; like Entyvio, it’s not an anti-TNF drug. Because anti-TNF drugs dominate the IBD market, the new data suggest that the question is no longer whether an alternative treatment strategy is effective; now it’s a matter of seeing which of the new treatment strategies will have the biggest impact.

Another notable event that affected survey responses was an announcement by Pfizer, which makes Xeljanz, regarding new safety concerns. Xeljanz (tofacitinib) is an approved treatment for rheumatoid arthritis, which, like IBD, is an autoimmune disease.

The Pfizer announcement revealed that, among rheumatoid arthritis patients over 50, a higher dose (10 mg) of Xeljanz was linked with an increased risk of pulmonary embolism (blood clots in the lung) and overall mortality.

According to Spherix, “This news appears to have already impacted gastroenterologists’ perceptions of Xeljanz negatively.” Compared to previous surveys, the number of respondents who thought Xeljanz was a significant advance for IBD treatment decreased, while the number reporting that it “now falls below their initial expectations” doubled.

Xeljanz is an inhibitor of JAK, an enzyme that helps make inflammatory signaling molecules. Over half of respondents reported a suspicion that the aforementioned adverse events may be a result of this inhibition, rather than being unique to Xeljanz.