Once touted as a potential powerhouse treatment for a variety of inflammatory conditions, Galapagos’ JAK inhibitor Jyseleca (filgotinib) saw its expectations tumble with a 2020 FDA rejection to treat rheumatoid arthritis followed by a 2023 failure in a phase 3 trial for Crohn’s disease.
But these days, on the market in Europe and under new owner Alfasigma, Jyseleca is making strides, albeit with a less ambitious game plan.
The Italian pharma has presented results from a phase 3 trial of Jyseleca, which has shown promise as a treatment for adults with the arthritic, inflammatory disease active axial spondyloarthritis (axSpA). In the Olinguito study, Jyseleca excelled in treating patients at both ends of the axSpA spectrum.
The more serious form is radiographic axSpA, also known as ankylosing spondylitis, which is characterized by damage to the sacroiliac joints and can be recognized on X-rays. The other variety is non-radiographic axSpA, which is detected by an MRI or another method of clinical investigation. This form of axSpA can progress to the radiographic type or can linger in its non-radiographic form for decades.
The trial was for those who had an inadequate response to conventional or biological treatments and included 258 patients with radiographic and 237 with non-radiographic axSpA. Both groups of patients received a daily 200-mg oral dose of Jyseleca for 16 weeks.
The primary endpoint was achieved in both groups, with enough patients showing a 40% improvement as outlined by the Assessment of SpondyloArthritis international Society. The trial demonstrated a similar safety profile to that seen in other studies of the treatment.
The results “clearly support the potential of filgotinib as a treatment option for patients living with axSpA at all stages of the disease,” Xenofon Baraliakos, M.D., Ph.D., professor for internal medicine and rheumatology at the Ruhr University in Germany, said in a release. “The burden of disease for these patients remains high as treatment options are limited. It is therefore encouraging that the primary endpoint for both axSpA indications was met in dedicated studies.”
Alfasigma said it will reveal trial data at a future medical conference. It also said it plans to submit results to the European Medicines Agency and the U.K.’s Medicines Healthcare products Regulatory Agency in hopes of gaining authorization to market Jyseleca.
AxSpA typically strikes young adults in their 20s and affects joints in the chest, spine and pelvis. The condition affects roughly 1% of the people in the world, causing significant pain, stiffness and reduced mobility.
Despite several anti-inflammatory treatment options, only about 40% to 50% of patients respond to treatment with only about 10% to 20% achieving remission or inactive disease activity within 16 to 24 weeks of treatment, Alfasigma said.
Developed by Belgian biotech Galapagos, Jyseleca was once promising enough to attract a $5 billion partnership deal with Gilead Sciences. However, after it came up short with the FDA because of toxicity issues, the California company halted its development of Jyseleca and relinquished most of its rights to the treatment.
In 2022, Galapagos reported sales of Jyseleca at 88 million euros ($95 million). While the figure increased to 112 million euros ($120 million) in 2023, it fell short of the company’s projection of 140 million euros to 160 million euros ($151 million to $173 million).
In October 2023, Galapagos sold the rights to Jyseleca to Alfasigma for 50 million euros ($54 million) upfront plus potential milestone payments of 120 million euros ($130 million) and royalties on sales in Europe. As part of the deal, Galapagos also agreed to pay 40 million euros ($43 million) by June of this year to fund continued development of Jyseleca, which is also on the market in Japan, the U.K. and a few other geographies.