Table of contents

• Trial overview
• Skin diseases studied
• Blood and immune diseases studied
• Children and adolescents in the trials
• Trial phases and study designs
• Main endpoints and what they mean

Trial overview

The data show that Ruxolitinib is being studied in many different clinical trials, not only for one disease but for several conditions. The studies are interventional, which means researchers give a treatment and then measure what happens. The trials include both completed and authorised studies, with phases from 1 to 4.^[1]

Some trials test Ruxolitinib alone, while others compare it with a vehicle cream (the same cream base without the active drug), placebo, or other therapies. Several studies also test Ruxolitinib in combination with other medicines. This helps researchers see whether the treatment works better alone or as part of a combined approach.^[2]

Skin diseases studied

Many of the trials focus on skin conditions. These include hidradenitis suppurativa, atopic dermatitis, vitiligo, prurigo nodularis, chronic hand eczema, and vitiligo with genital involvement.^[1]

In hidradenitis suppurativa, two phase 3 trials, TRuE-HS1 and TRuE-HS2, each plan to enroll 550 participants and look at the response after 16 weeks. The main outcome is HiSCR75, which means at least a 75% drop in the number of inflammatory nodules, with no increase in abscesses or draining tunnels.^[1]

In atopic dermatitis, one phase 3b study is for children and adolescents from 6 to under 18 years, and another phase 3b study is for adults. Both compare Ruxolitinib cream with vehicle cream and measure skin improvement with EASI75, while the adult study also measures IGA-TS at week 8.^[3]

In vitiligo, one phase 3 study is for children aged 6 to under 12 years with non-segmental vitiligo, and another phase 2 study looked at genital vitiligo. These studies measure pigment improvement, including F-VASI75 and genital VNS scores, which show whether the affected skin looks less noticeable.^[4]

Prurigo nodularis and chronic hand eczema are also studied in controlled trials. In prurigo nodularis, the main endpoint is WI-NRS4 response at week 12, which means a 4-point improvement in itch score. In chronic hand eczema, the endpoint is IGA-CHE-TS at week 16, a score used to rate how well the skin has improved.^[5]

Blood and immune diseases studied

Ruxolitinib is also being tested in blood and immune-related diseases such as myelofibrosis, polycythemia vera, essential thrombocythemia, graft-versus-host disease, hemophagocytic lymphohistiocytosis, and classical Hodgkin lymphoma.^[6]

In myelofibrosis, several studies look at spleen size and symptoms. Examples include trials combining Ruxolitinib with selinexor, navtemadlin, axatilimab, navitoclax, elritercept, or other investigational drugs. The main goals are to reduce spleen volume, improve symptom scores, and check safety in people who may be treatment-naïve, have anemia, or have disease that did not respond well to earlier JAK inhibitor treatment.^[7]

In polycythemia vera and essential thrombocythemia, the trials compare Ruxolitinib with the best available therapy or with other first-line options. One phase 3 study in high-risk polycythemia vera uses event-free survival as the main outcome, and another phase 2 study in essential thrombocythemia looks at durable clinicohematologic response.^[8]

For graft-versus-host disease, the studies include newly diagnosed chronic disease, steroid-refractory chronic disease, and steroid-refractory acute disease. These trials often measure overall response at a set time point, such as 6 months, day 28, or week 25, to see whether the disease improves without needing extra systemic therapy.^[9]

Other trials study Ruxolitinib in children with hemophagocytic lymphohistiocytosis, in adults with acquired hemophagocytic syndrome in intensive care, and in relapsed or refractory classical Hodgkin lymphoma. In these studies, the main outcomes include survival until stem cell transplant, improvement in organ failure scores, and complete response rates.^[10]

Children and adolescents in the trials

Several studies are designed specifically for younger patients. Examples include children with non-segmental vitiligo, children and adolescents with moderate atopic dermatitis, children with hemophagocytic lymphohistiocytosis, and children with acute lymphoblastic leukemia or relapsed/refractory leukemia or lymphoma with JAK/STAT pathway changes.^[11]

These trials are important because they test whether Ruxolitinib can be studied safely and effectively in younger age groups, where the disease burden and treatment needs may be different from adults. Some pediatric studies also compare results with external controls or standard chemotherapy, rather than using only placebo.^[11]

Trial phases and study designs

The trial list includes phase 1 studies, which mainly focus on safety, dose-finding, and early signals of activity. It also includes phase 2 studies, which look more closely at whether the treatment works, and phase 3 studies, which are larger and often compare against vehicle, placebo, or standard therapy.^[7]

Some studies are double-blind, meaning neither the participant nor the research team knows who receives the active treatment during the study period. Others are open-label, which means both sides know what treatment is being given. A few are rollover studies, designed to allow continued treatment and ongoing safety follow-up for people already in a parent study.^[5]

Main endpoints and what they mean

The endpoint is the main result the researchers want to measure. In these Ruxolitinib trials, endpoints include skin response scores, spleen volume reduction, symptom score changes, survival, overall response, and safety outcomes such as adverse events.^[1]

For skin studies, common endpoints are EASI75, HiSCR75, WI-NRS4, IGA-TS, F-VASI75, and genital VNS. These are scoring systems that show whether the skin has improved, how much itching has changed, or whether pigment loss is less visible.^[4]

For blood and immune disease studies, common endpoints include SVR35, total symptom score change, overall response, event-free survival, and survival until HSCT. These measures help show whether the disease is better controlled, whether the spleen shrinks, and whether patients stay well enough to reach transplant or avoid major events.^[8]

Safety is also a major focus. Several studies track adverse events, serious adverse events, laboratory tests, physical examinations, and ECG findings to understand how well the treatment is tolerated in the studied population.^[12]