Galapagos Achieves Positive Results for its TYK2 Inhibitor in Dermatomyositis
Belgian laboratory Galapagos announced on December 18 the results of two phase 3 studies evaluating its selective TYK2 inhibitor, GLPG3667. The trial conducted in dermatomyositis met its primary endpoint, while the one on systemic lupus erythematosus did not demonstrate statistical significance on the primary criterion.
Successful Results in Dermatomyositis Study
The GALARISSO study conducted in dermatomyositis achieved its primary objective, the press release states. Administered at 150 mg per day in addition to standard treatment in 21 patients, GLPG3667 demonstrated a statistically significant clinical benefit on the total improvement score at 24 weeks, compared to the placebo administered to 19 patients. The p-value was established at 0.0848 with an alpha of 14.26, the company specifies, with the pre-specified statistical significance threshold set at 10%. The drug candidate also showed significant clinical improvements on several secondary disease activity criteria. According to Galapagos, the safety and tolerance profile proved favorable during the 24-week treatment period. An extension of the study for an additional 24 weeks was offered to all patients.
Lack of Statistical Significance in Systemic Lupus Erythematosus Study
In the GALACELA study on systemic lupus erythematosus, GLPG3667 did not reach statistical significance in the dose-response primary criterion analysis, the group reports. The molecule was tested at two daily dosages, 75 mg in 59 patients and 150 mg in 64 patients, in addition to standard treatment, compared to 63 patients on placebo. The primary objective was to evaluate the SRI-4 response index at 32 weeks. According to the press release, the drug candidate nevertheless showed numerical improvements over placebo on several secondary criteria, particularly on skin manifestations. The study is currently ongoing, and the final 48-week data, expected in the second quarter of 2026, will be crucial in determining the next steps of the program, the company emphasizes.
Exploring Strategic Alternatives for GLPG3667
In light of these results, Galapagos indicates it is evaluating all strategic alternatives for GLPG3667. The group is particularly considering resuming partnership discussions announced earlier this year to accelerate development in dermatomyositis and potentially in other severe autoimmune diseases with high medical need. CEO Henry Gosebruch stated that the positive results in dermatomyositis validate the anti-inflammatory potential of the selective TYK2 inhibitor. He also mentioned the favorable safety profile observed to date. According to the press release, Gilead has temporarily waived certain rights provided in the 10-year collaboration agreement between the two groups, thus allowing Galapagos to explore external partnership opportunities for GLPG3667. The company plans to present the data at an upcoming medical congress.
