A Phase 2 interventional study of PTC844 and Placebo in Rheumatoid Arthritis, sponsored by PTC Therapeutics. Recruiting at 26 sites in 4 countries. Open to participants aged 18 Years to 70 Years. Per ClinicalTrials.gov, last updated 2026-11-06.
Sponsored by PTC Therapeutics · Phase 2, Interventional, and Treatment
This study is designed to assess the safety, pharmacokinetics (PK), and biomarker effects of PTC844 compared to placebo in participants with active rheumatoid arthritis (RA).
3,332 studies on the registry are indexed under Arthritis, Rheumatoid; 443 are open to participants now.
This study's planned enrollment of 75 is below the median of 96 across 2,220 interventional studies indexed under Arthritis, Rheumatoid.
Browse Arthritis, Rheumatoid studies →PTC Therapeutics is the lead sponsor of 65 studies on the registry; 3 are open to participants now.
Of its 18 completed or terminated interventional studies of FDA-regulated products, 14 (78%) have results posted.
Counted across the registry records on this site, refreshed daily.
Key Inclusion Criteria:
Key Exclusion Criteria:
Note: Other protocol-defined inclusion/exclusion criteria may apply.
Underlined terms in the criteria open these too. Explained by clinicaltrials.gg, not part of the registry record. The study team decides who can take part.
Judged by the study doctor to matter for your health or for the study. It is a doctor’s decision, so ask the study team if you are unsure whether something counts.
Malignancy means cancer. Criteria about another or earlier malignancy ask whether you have had a different cancer, usually within a set number of years.
Some are commonly allowed, such as treated skin cancers other than melanoma and early cancers removed completely — check the exceptions this study lists.
An allergy, or another reaction of the immune system, to a substance. “Hypersensitivity to the study drug” means a known allergic reaction to it — not every side effect a medicine can have.
The other ingredients in a medicine besides the active drug, such as fillers, colours or preservatives.
Clinically significant
Judged by the study doctor to matter for your health or for the study. It is a doctor’s decision, so ask the study team if you are unsure whether something counts.
Explained by clinicaltrials.gg, not part of the registry record. The study team decides who can take part.
Cancer (malignancy)
Malignancy means cancer. Criteria about another or earlier malignancy ask whether you have had a different cancer, usually within a set number of years.
Some are commonly allowed, such as treated skin cancers other than melanoma and early cancers removed completely — check the exceptions this study lists.
Explained by clinicaltrials.gg, not part of the registry record. The study team decides who can take part.
Hypersensitivity
An allergy, or another reaction of the immune system, to a substance. “Hypersensitivity to the study drug” means a known allergic reaction to it — not every side effect a medicine can have.
Explained by clinicaltrials.gg, not part of the registry record. The study team decides who can take part.
Excipients
The other ingredients in a medicine besides the active drug, such as fillers, colours or preservatives.
Explained by clinicaltrials.gg, not part of the registry record. The study team decides who can take part.
Participants will receive PTC844 at a low dose once daily (QD) orally for 12 weeks.
Drug: PTC844
Participants will receive PTC844 at a high dose QD orally for 12 weeks.
Drug: PTC844
Participants will receive placebo matching to PTC844 QD orally for 12 weeks.
Drug: Placebo
PTC844 will be administered per schedule specified in the arm description.
Placebo matching to PTC844 will be administered per schedule specified in the arm description.
Number of Participants With Treatment-emergent Adverse Events (TEAEs)
Time frame: Baseline up to Week 16
Change From Baseline to Week 2 in Dihydroorotate (DHO)
Time frame: Baseline, Week 2
Change From Baseline to Week 12 in C-reactive Protein (CRP)
Time frame: Baseline, Week 12
Change From Baseline to Week 12 in Erythrocyte Sedimentation Rate (ESR)
Time frame: Baseline, Week 12
Change From Baseline in DHO Over Time
Time frame: Baseline up to Week 16
Maximum Observed Plasma Concentration (Cmax) of PTC844
Time frame: Baseline up to Week 16
Area Under the Concentration-time Curve From Time 0 to the Time of Last Quantifiable Concentration (AUClast)
Time frame: Baseline up to Week 16
Time to Reach Cmax (Tmax)
Time frame: Baseline up to Week 16
Number of Participants Achieving ≥20% Improvement in American College of Rheumatology Score (ACR20)
Time frame: Week 12
Number of Participants Achieving ≥50% Improvement in American College of Rheumatology Score (ACR50)
Time frame: Week 12
Number of Participants Achieving ≥70% Improvement in American College of Rheumatology Score (ACR70)
Time frame: Week 12
Change From Baseline to Week 12 in 28-Joint Disease Activity Score-CRP (DAS28-CRP)
Time frame: Baseline, Week 12
Change From Baseline to Week 12 in 28-Joint Disease Activity Score-ESR (DAS28-ESR)
Time frame: Baseline, Week 12
Change From Baseline to Week 12 in 20- Item Disability Scale and Heath Assessment Questionnaire (HAQ-DI)
Time frame: Baseline, Week 12
From the registry record's own update history. This site started tracking changes on Sep 25, 2026; for anything earlier, see the record history on ClinicalTrials.gov ↗
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