Skip to main content

How long does it take for Skyrizi to work?

Medically reviewed by Melisa Puckey, BPharm. Last updated on Aug 11, 2022.

Official answer

  • Skyrizi can start to show an improvement in psoriasis and psoriatic arthritis in 4 weeks for some patients, with an increasing number of patients having a reduction in symptoms over 16 weeks and beyond.
  • Using Skyrizi for psoriasis 6% of patients had a 90% reduction in their psoriasis score at four weeks. By week sixteen, 76% of patients had a 90% reduction in their psoriasis score.
  • When using Skyrizi for psoriatic arthritis at 4 weeks 25.7% of Skyrizi patients had psoriatic arthritis symptoms reduced by 20%, and by 24 weeks this had increased to 57.3% of Skyrizi patients.
  • When using Skyrizi for Crohn's disease, patients start to have a clinical response within 4 weeks and by 12 weeks 23% more Skyrizi patients had a clinical response compared to placebo.

Skyrizi (risankizumab-rzaa) is an injection given under the skin (subcutaneous injection) to treat patients who have moderate or severe plaque psoriasis (raised, silvery flaking of the skin) and for active psoriatic arthritis (PsA) which is a systemic inflammatory disease which affects the skin and joints.

How long does it take for Skyrizi to work for Psoriasis?

First of all, how do you measure improvement in psoriasis?

  • To measure how good or bad your psoriasis is, a score is used called the PASI (Psoriasis Area and Severity Index).
  • It scores your psoriasis on redness, thickness, amount of scaling and how much of the body is affected.
  • If your psoriasis score has a 90% reduction it is called PASI 90. If you had a 100% reduction in your PASI score would be a PASI 100.

Data from the LIMMitless phase 3 study looked at the percentage of psoriasis patients who achieved 90% improvement in their PASI score (PASI 90) and results showed that Skryrizi starts working:

  • Within the first 4 weeks in which 6% Skyrizi patients achieved PASI90.
  • By 8 weeks 44% of patients achieved PASI90.
  • By 16 weeks 76% of patients achieved PASI90, compared to 5% for the placebo group.
  • By 52 weeks 86% of patients achieved PASI90.

How long does it take for Skyrizi to work for psoriatic arthritis?

Improvements in psoriatic arthritis are measured by American College of Rhematology (ACR) Criteria which is a combined score of the number of tender joints, the number of swollen joints and also includes three of the following five criteria:

  • patient assessment on disease severity,
  • physician assessment on disease severity,
  • level of functional ability,
  • level of pain
  • erythrocyte sedimentation rate (ESR) or C-reactive protein (CRP).

An ACR20 is when there is a 20% improvement in tender or swollen joint counts, as well as a 20% improvement in at least three of the other five above criteria.

The phase 3 KEEPsAKE 1 trial showed how long it took for Skyrizi to improve psoriatic arthritis. The results of the study showed the number of Skyrizi patients who had a 20% improvement (ACR20) in their psoriatic arthritis, compared to placebo patients.

The percentage of patients that achieved a 20% improvement in psoriatic arthritis:

  • At four weeks Skyrizi 25.7%, compared to placebo 13.7%. (Difference 25.7% - 13.7% = 12%)
  • At 8 weeks Skyrizi 43.9%, compared to placebo 28.8%. (Difference 43.9% - 28.8% = 15.1%)
  • At 16 weeks Skyrizi 56.3%, compared to placebo 33.4%. (Difference 56.3% - 33.4% = 22.9%)
  • At 24 weeks Skyrizi 57.3%, compared to placebo 33.5%. (Difference 57.3% - 33.5% = 23.8%)

How long does it take for Skyrizi to work for Crohn’s disease?

For Crohn’s disease Skyrizi starts to have a significant clinical response in as early as 4 weeks. A clinical response for Crohn’s disease is defined as a 100-point reduction in Crohn's Disease Activity Index [CDAI] ).
After 12 weeks 23% more Skyrizi patients clinical response to Skyrizi compared to placebo patients (Skyrizi 60% - placebo 37%= 23%)

Bottom Line:

  • Skyrizi injection when used for psoriasis starts to work within four weeks for some patients, with 6% of patients seeing a 90% reduction in their PASI score.
  • Skyrizi patients continued to see an improvement in plaque psoriasis symptoms, so that by week 52, 86% have a PASI 90 and by 59% achieve a PASI 100.
  • When using Skyrizi for psoriatic arthritis, improvement starts within four weeks with 25.7% of Skyrizi patients reaching a 20% improvement in ACR (American College of Rhematology) Criteria.
  • Skyrizi psoriatic arthritis patients had further improvement by week 24 with 57.3% of the Skyrizi patients reaching ACR20.
  • For Crohn's disease after 12 weeks 23% more Skyrizi patients clinical response to Skyrizi compared to placebo patients (Skyrizi 60% - placebo 37%= 23%)

Related medical questions

Drug information

Related support groups