Evaluation of patients with limited primary (initial) response to or secondary loss of response to risankizumab
Test Id | Reporting Name | Available Separately | Always Performed |
---|---|---|---|
RISA | Risankizumab, S | Yes | Yes |
RISAB | Risankizumab Ab, S | No | Yes |
For more information see Ulcerative Colitis and Crohn Disease Therapeutic Drug Monitoring Algorithm.
RISA: Liquid Chromatography Mass Spectrometry (LC-MS)
RISAB: Electrochemiluminescent-Bridging Immunoassay (ECLIA)
AbbVie
Anti-IL23 blocker
Antibodies-to-Risankizumab
Crohn's disease
Plaque psoriasis
Psoriatic arthritis
RISA
RISAB
Risankizumab
Risankizumab antibodies
RISAP
Skyrizi
Skyrizi antibodies
For more information see Ulcerative Colitis and Crohn Disease Therapeutic Drug Monitoring Algorithm.
Serum
Patient Preparation: For 12 hours before specimen collection, patient should not take multivitamins or dietary supplements (eg, hair, skin, and nail supplements) containing biotin (vitamin B7).
Supplies: Sarstedt Aliquot Tube, 5 mL (T914)
Container/Tube:
Preferred: Serum gel
Acceptable: Red top
Submission Container/Tube: Plastic vial
Specimen Volume: 1.5 mL
Collection Instructions:
1. Draw blood immediately before next scheduled dose (trough specimen).
2. Within 2 hours of collection, centrifuge, and aliquot serum into a plastic vial.
If not ordering electronically, complete, print, and send Gastroenterology and Hepatology Test Request (T728) with the specimen.
0.75 mL
Gross hemolysis | OK |
Gross lipemia | Reject |
Gross icterus | OK |
Heat-treated specimens | Reject |
Specimen Type | Temperature | Time | Special Container |
---|---|---|---|
Serum | Refrigerated (preferred) | 28 days | |
Frozen | 28 days |
Evaluation of patients with limited primary (initial) response to or secondary loss of response to risankizumab
For more information see Ulcerative Colitis and Crohn Disease Therapeutic Drug Monitoring Algorithm.
Risankizumab (Skyrizi, AbbVie) is a humanized IgG1 kappa therapeutic monoclonal antibody approved for the treatment of moderate to severe plaque psoriasis, psoriatic arthritis, ulcerative colitis, and Crohn disease.(1,2) Risankizumab targets interleukin 23A (IL-23p19), binding with high affinity to the p19 subunit and inhibiting further action.(3)
Therapeutic drug monitoring (TDM) has become standard-of-care for biologic therapies used in inflammatory bowel disease (IBD). In this context, TDM requires both quantitation of the therapeutic monoclonal antibody and assessment for the presence of anti-drug antibodies. Accurate interpretation of drug quantitation requires knowledge regarding patient diagnosis, drug dosage, and treatment schedule. Patients with plaque psoriasis or psoriatic arthritis are treated with 150 mg subcutaneously at weeks 0, 4, and every 12 weeks thereafter. The steady state maximum concentration (Cmax) and trough concentration (Ctrough) are estimated to be 12 mcg/mL and 2 mcg/mL, respectively. Patients with Crohn disease are treated with 600 mg intravenously at weeks 0, 4, and 8, followed by 180 mg or 360 mg subcutaneously at week 12 and every 8 weeks thereafter. During induction weeks 8 through 12, the median Cmax is estimated to be 156 mcg/mL, and the Ctrough is estimated to be 38.8 mcg/mL, according to the drug package insert. Steady state is achieved at 28 weeks after starting treatment in the dosing regimen for Crohn disease. Median Cmax and Ctrough concentrations measured during weeks 40 through 48 of maintenance phase (or weeks 52-60 from start of treatment) are estimated to be 14.0 mcg/mL and 4.1 mcg/mL, respectively, for 180 mg dose or 28.0 mcg/mL and 8.1 mcg/mL, respectively, for 360 mg dose.(4)
The other important aspect of TDM for therapeutic monoclonal antibodies is detection of anti-drug antibodies. Similar to other therapeutic antibodies, risankizumab is immunogenic. Development of antibodies to risankizumab (ATRs) may increase drug clearance in treated patients and/or neutralize the drug effect, thereby potentially contributing to loss-of-response. Clinical trials have shown ATRs occur at rates of about 24% for plaque psoriasis, 12% for psoriatic arthritis, and 3.4% for Crohn disease.
In the context of limited initial response or loss-of-response over time to risankizumab, measurement of circulating drug concentrations and assessment for ATRs can help to guide patient management. For example, patients with low risankizumab trough concentrations in the absence of ATRs might benefit from dose escalation in an attempt to increase the circulating amount of the drug. In contrast, for patients with low drug concentrations and a detectable ATR, transition to a new drug therapy may be indicated.
RISANKIZUMAB QUANTITATION:
Risankizumab lower limit of quantitation =1.0 mcg/mL
RISANKIZUMAB ANTIBODIES:
Antibodies to risankizumab: <20.0 ng/mL
The optimal therapeutic serum concentration of risankizumab associated with favorable outcomes in Crohn disease is not known at this time. The current recommendation is to use the lowest dosing regimen that maintains response. According to the package insert, concentrations of risankizumab at steady state ranged from 4.1 mcg/mL (trough) to 14 mcg/mL (peak) at 180 mg dosing and 8.1 mcg/mL (trough) to 28 mcg/mL (peak) at 360 mg dosing. Steady state is achieved 28 weeks after initiation of therapy for the dosing regimen in Crohn disease.
The presence of detectable anti-risankizumab antibodies may be associated with increased risankizumab clearance and lower circulating concentrations of risankizumab in serum. Low trough concentrations of risankizumab may be correlated with loss of response to the drug.
Clinical management decisions for patients receiving risankizumab treatment should not be based solely on quantitation of risankizumab or assessment of antibodies to risankizumab (ATRs). Test results must be interpreted within the clinical context of the patient.
Therapeutic ranges have not been established for risankizumab quantitation. Therapeutic concentrations of risankizumab may vary according to the disease (eg, Crohn disease vs psoriatic arthritis vs plaque psoriasis). The limit of quantitation of the liquid chromatography time-of-flight (TOF) mass spectrometry method is 1.0 mcg/mL and reported in place of a reference interval with every test report.
Interference with the ATR assay, in the form of depressed signal, was observed in samples containing more than 400 ng/mL biotin.
1. Feagan BG, Panes J, Ferrante M, et al. Risankizumab in patients with moderate to severe Crohn's disease: an open-label extension study. Lancet Gastroenterol Hepatol. 2018;3(10):671-680
2. Ferrante M, Panaccione R, Baert F, et al. Risankizumab as maintenance therapy for moderately to severely active Crohn's disease: results from the multicentre, randomised, double-blind, placebo-controlled, withdrawal phase 3 FORTIFY maintenance trial. Lancet. 2022;399(10340):2031-2046
3. Pang Y, D'Cunha R, Winzenborg I, Veldman G, Pivorunas V, Wallace K. Risankizumab: Mechanism of action, clinical and translational science. Clin Transl Sci. 2024;17(1):e13706
4. Skyrizi. Package insert. AbbVie, Inc.; Revised March 2024. Accessed June 3, 2024. Available at www.rxabbvie.com/pdf/skyrizi_pi.pdf
Risankizumab Quantitation:
Risankizumab is extracted from serum and measured by liquid chromatography mass spectrometry.(Unpublished Mayo method)
Risankizumab Antibodies:
Testing for antibodies to risankizumab is accomplished using a laboratory-developed immunoassay.(Unpublished Mayo method)
Weekly
This test was developed and its performance characteristics determined by Mayo Clinic in a manner consistent with CLIA requirements. It has not been cleared or approved by the US Food and Drug Administration.
80299
82397
Test Id | Test Order Name | Order LOINC Value |
---|---|---|
RISAP | Risankizumab QN with Antibodies, S | 105194-5 |
Result Id | Test Result Name |
Result LOINC Value
Applies only to results expressed in units of measure originally reported by the performing laboratory. These values do not apply to results that are converted to other units of measure.
|
---|---|---|
621304 | Risankizumab, S | 105041-8 |
621769 | Risankizumab Ab, S | 105195-2 |
621812 | RISAB Interpretation | 59462-2 |
Change Type | Effective Date |
---|---|
New Test | 2024-07-30 |