MANTA and MANTA-RAy safety readouts boost Jyseleca’s prospects in the US

Following Galapagos’ announcement of pooled interim results from its ongoing MANTA and MANTA-RAy safety studies for Jyseleca (filgotinib);

Rose Joachim, Pharma Analyst at GlobalData, a leading data and analytics company, offers her view:

“Interim data from MANTA and MANTA-RAy should ease fears that Jyseleca may negatively impact sperm health in men with inflammatory bowel disease (IBD) or rheumatic diseases. Although the trials were not powered for comparison across groups, fewer patients treated with Jyseleca (200mg) versus placebo experienced a 50% or greater decline in sperm concentration over the initial 13-week double-blind treatment period. These data renew hope for Jyseleca in the US IBD space.

“Although pending outcomes from these trials factored into Jyseleca’s complete response letter in rheumatoid arthritis (RA), sperm toxicity data will arguably be of greater importance when considering the drug’s applications in ulcerative colitis (UC) and Crohn’s disease (CD), as these diseases are more likely to affect younger men. According to GlobalData’s epidemiological analysis, in 2021, men between the ages of 20 and 65 will comprise around 35% of the total diagnosed prevalent cases of CD and UC (among patients 20 years of age or older). In contrast, this group of patients accounts for only 13% of cases in RA.

“If the Food and Drug Administration (FDA) is satisfied with Galapagos’ interim results from MANTA and MANTA-RAy, a US filing for Jyseleca in UC could occur as early as this year, with pending approval in 2022. However, this date could still be pushed out further, potentially to 2023, if the FDA also requires data from 26-week or even 52-week time points. Considering the extensive safety data requested when evaluating the drug’s filing for RA, it is likely the FDA will want to see these later time points. Assuming an existing UC label and positive Phase III data, approval in CD would follow soon after.

“Gilead withdrew its FDA filing for Jyseleca in RA, but UC and CD are still very promising markets for the drug in the US. Although IBD is a smaller market than RA, with expected 2021 sales of $13.2bn versus $20.9bn in the US, according to GlobalData, Jyseleca has similar or perhaps even greater sales potential in UC and CD due to more limited competition. In the US, there are currently five and six targeted immunomodulating drugs approved for the treatment of CD and UC, respectively—half the number available for RA. If approved, GlobalData forecasts sales for Jyseleca will reach $95.1m and $129m in UC and CD, respectively, by 2029.”

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