The likelihood that patients treated with apremilast for psoriatic arthritis (PsA) will have low disease activity (LDA) or remission by week 52 is greater for patients with moderate disease activity (MDA) compared with those with high disease activity (HDA), according to study results published in Arthritis Care & Research. Patients who achieved the Clinical Disease Activity for Psoriatic Arthritis (cDAPSA) targets by week 52 also had mild or no arthritis or other PsA manifestations.
Using the pooled data from the phase 3 randomized Psoriatic Arthritis Long-Term Assessment of Clinical Efficacy (PALACE 1, 2, and 3) studies, which evaluated the oral phosphodiesterase 4 inhibitor apremilast, investigators sought to identify the subgroups of patients most likely to benefit from apremilast therapy. Probability analyses were performed using multiple imputations for discontinuations and missing values to assess the likelihood that patients would achieve cDAPSA targets by week 52. Longitudinal analyses grouped by cDAPSA category were performed to assess musculoskeletal and nonmusculoskeletal domains of PsA.
Of the 1493 participants randomly assigned to receive ≥1 dose of apremilast in the PALACE 1-3 studies (placebo, n=496; apremilast 30 mg twice a day, n=497; apremilast 20 mg twice a day, n=500), 494 who had been randomly assigned to receive apremilast 30 mg at baseline and baseline cDAPSA scores available were included in the probability analyses assessing the likelihood of achieving cDAPSA LDA or remission. A total of 375 patients were randomly assigned to receive apremilast 30 mg at baseline with available week 52 cDAPSA scores were included in the longitudinal analyses of cDAPSA and musculoskeletal and nonmusculoskeletal domains of PsA.
Of the 494 patients included in probability analyses, 46.9% with MDA at baseline achieved LDA or remission by week 52 compared with 24.9% with HDA at baseline. At week 16, patients with LDA at baseline showed response rates of 40.0% remission, 40.0% LDA, 20% MDA, and 0% HAD; patients with MDA at baseline showed response rates of 7.0% remission, 29.8% LDA, 44.7% MDA, and 18.4% HAD; and patients with HAD at baseline showed response rates of 2.1% remission, 11.5% LDA, 38.1% MDA, and 48.3% HAD.
Among patients with MDA at baseline, achieving LDA or remission at week 16 was associated with a high probability (58.9%-88.5%) of maintaining target improvements through week 52; a mean reduction of ≥30% in cDAPSA score by week 16 was associated with a 63% probability of achieving treatment targets by week 52.
For the 375 patients included in longitudinal analyses, achieving treatment targets with apremilast was associated with continuous improvements in disease activity and mild or no arthritis and other PsA manifestations. Researchers indicated that achieving cDAPSA targets with apremilast was associated with control of PsA musculoskeletal and nonmusculoskeletal domains not included in the cDAPSA.
Study limitations included the use of Maastricht Ankylosing Spondylitis Enthesitis Score to assess enthesitis because of which peripheral enthesitis may have been indirectly accounted for with the cDAPSA.
“Our findings indicate that patients with [MDA] at baseline have a higher likelihood of achieving optimal outcomes with apremilast compared with those in HDA at baseline. Early and partial responses by [week] 16 were associated with achieving long-term treatment targets. Finally, the results support the use of the cDAPSA to monitor patients treated with apremilast given that domains not captured by the cDAPSA traveled in the same direction as the cDAPSA. At a population level, patients who achieved cDAPSA [remission] or LDA also had no or mild musculoskeletal and [nonmusculoskeletal] disease manifestations,” the researchers concluded.
Disclosure: Several study authors declared affiliations with the pharmaceutical industry. Please see the original reference for a full list of authors’ disclosures.
Mease PJ, Gladman DD, Ogdie A, et al. Treatment to target in psoriatic arthritis with apremilast: Probability of achieving targets and comprehensive control of disease manifestations [published online January 7, 2020]. Arthritis Care Res (Hoboken). doi:10.1002/acr.24134