Biomarkers and methods for assessing psoriatic arthritis disease activity

A method for generating a protein level score comprising:

• performing at least one immunoassay on a first blood sample from a subject previously diagnosed with psoriatic arthritis (PsA), to generate protein level data for each protein marker of a plurality of protein markers, wherein the plurality of protein markers comprises a plurality of test markers comprising at least four markers selected from chitinase 3-like 1 (cartilage glycoprotein-39) (CHI3L1);
• C-reactive protein, pentraxin-related (CRP);
• epidermal growth factor (beta-urogastrone) (EGF);
• interleukin 6 (interferon, beta 2) (IL6);
• leptin (LEP);
• matrix metallopeptidase 1 (interstitial collagenase) (MMP1);
• matrix metallopeptidase 3 (stromelysin 1, progelatinase) (MMP3);
• resistin (RETN);
• serum amyloid A1 (SAA1);
• tumor necrosis factor receptor superfamily, member 1A (TNFRSF1A);
• vascular cell adhesion molecule 1 (VCAM1);
• or, vascular endothelial growth factor A (VEGFA);
• and
• combining the protein level data for each test marker to generate the protein level score.

A method for providing a quantitative measure of psoriatic arthritis (PsA) disease activity in a subject previously diagnosed with PsA comprising:

• performing at least one immunoassay on a first sample from the subject to generate a first dataset comprising quantitative data comprising at least four markers selected from chitinase 3-like 1 (cartilage glycoprotein-39) (CHI3L1);
• C-reactive protein, pentraxin-related (CRP);
• epidermal growth factor (beta-urogastrone) (EGF);
• interleukin 6 (interferon, beta 2) (IL6);
• leptin (LEP);
• matrix metallopeptidase 1 (interstitial collagenase) (MMP1);
• matrix metallopeptidase 3 (stromelysin 1, progelatinase) (MMP3);
• resistin (RETN);
• serum amyloid A1 (SAA1);
• tumor necrosis factor receptor superfamily, member 1A (TNFRSF1A);
• vascular cell adhesion molecule 1 (VCAM1);
• or, vascular endothelial growth factor A (VEGFA);
• and
• applying an algorithm to said first dataset to determine a first disease activity score, wherein said first disease activity score provides a quantitative measure of PsA disease activity in said subject.

A method for recommending a therapeutic regimen in a subject previously diagnosed with psoriatic arthritis (PsA), the method comprising:

• a) performing, at a first time point, a first immunoassay on a first sample from the subject to generate a first score based on a first set of quantitative data, wherein the first set of quantitative data comprises expression data for at least four biomarkers selected from chitinase 3-like 1 (cartilage glycoprotein-39) (CHI3L1);
• C-reactive protein, pentraxin-related (CRP);
• epidermal growth factor (beta-urogastrone) (EGF);
• interleukin 6 (interferon, beta 2) (IL6);
• leptin (LEP);
• matrix metallopeptidase 1 (interstitial collagenase) (MMP1);
• matrix metallopeptidase 3 (stromelysin 1, progelatinase) (MMP3);
• resistin (RETN);
• serum amyloid A1 (SAA1);
• tumor necrosis factor receptor superfamily, member 1A (TNFRSF1A);
• vascular cell adhesion molecule 1 (VCAM1);
• or, vascular endothelial growth factor A (VEGFA);
• b) performing, at a second time point that is a time period after the first time point, a second immunoassay on a second sample from the subject to generate a second score based on a second set of quantitative data, wherein the second set of quantitative data comprises expression data for the at least four biomarkers;
• c) determining whether there is a difference between the first score and the second score;
• and
• d) recommending a therapeutic regimen, or modifying an existing therapeutic regimen, based on the difference between the first and second scores.